Dissociative identity disorder | definition, causes, symptom, types and treatment|

Dissociative identity disorder (DID)

Dissociative identity disorder (DID) is a mental disorder in which an individual has two or more distinct identities in his personality. Each identity of a DID person controls their behavior at different times, and every identity is so unique, having its own personality, history, behavior, traits, likes and dislikes. The first case of DID was reported in 1811 for "Mary Reynolds" and was documented by the physician "Samul Mitchel". "Dissociative Identity Disorder" (DID) was previously known as "Multiple Personality Disorder" (MPD). "Multiple Personality Disorder" was renamed to "Dissociative Identity Disorder" in 1994. The World Health Organization, however, continues to use the term "Multiple Personality Disorder," whereas most books and research now use the new term, Dissociate Identity Disorder (DID).
 
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Dissociative identity disorder definition 

"Dissociative identity disorder is a mental condition in which a person has two or more distinct identities or personalities, each with its own pattern of perception, behavior, and interaction with the environment."
In brief, the "main personality" of a DID (Dissociate Identity Disorder) person is inert, supine, depressed, and dependent. Their alternative personalities have two or multiple distinct identities called alters. The person himself is not aware of his condition. Individuals with DID (Dissociate Identity Disorder) are consciously aware of every alternating or split identity. However, the person has a memory gap (amnesia), which causes difficulty remembering daily tasks, events, meetings, and information. Every "alter" of DID has its own distinct names, identities, behavior, gender, age, temperament, self-image, background, and history that the individual has perceived, and some patients have "alters" of behaving like animals. At least two of these personalities repeatedly assert themselves to control the affected person's behavior and consciousness. 

Prevalence 

Dissociative identity disorder (DID) is a rare disorder affecting around 1% to 3% of the total population, and it begins in childhood. Between the ages of two and eight, 97-98% of DIDs reported being physically and sexually abused as children. Trauma in early childhood, such as the violent death of another person, torture, or neglect, is responsible for 2% of DIDs. Women are more affected than men because they are more often abused, but it affects both genders. 

Causes

There are a variety of reasons that can cause DID. The main cause of dissociative identity disorder is repeated physical, emotional, sexual, or mental abuse beginning in early childhood. 
  • The trauma in one’s past can be an important factor in triggering this problem. Environmental factors include living through a war; natural disasters like famines and earthquakes; torture; kidnapping; or invasive medical procedures.
  • Absence of safe and nurturing resources to overwhelm abuse or trauma. 
  •  Home environment if it is violent, frightening, and unpredictable. 
The dissociate personality "alter" is the safe way to overcome the trauma. 

Alters

The different personalities that occur are called "alters." Alters may have experienced a distinct personal history, self-image, and identity, including a separate name, as well as age. At least two of these personalities recurrently take control of the person’s behavior. Sometimes the two are more alter can co-exist, called co-fronting. Identities can resemble the main personality or they may be a different age, sex, race, or religion. Each personality can have its own posture, set of gestures, and hairstyle, as well as a distinct way of dressing. some alters may speak in foreign languages or with an accent.

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Symptoms 

  • The individual experiences two or more distinct identities or personality states. 
  • Identity disruption involves a change in self-perception as well as changes in behavior, consciousness, memory, and perception. 
  • The individual's inability to remember large parts of their childhood. 
  • Suicide attempts or self-injury. 
  • Differences in handwriting occur from time to time. 
  • Sometimes new identities are not human, but are animals or imaginary creatures with frequent bouts of memory loss or "lost time." 
  • Memories that return unexpectedly, as in a flashback. 
  • They have sleep problems like insomnia, sleepwalking, and nightmares. 
  • Social isolation, hallucinations, delusions, depression, anxiety, and confusion are present in the personality. 
  • A sudden and unexpected shift in mood person have a feeling of disconnection from themselves and the environment. of dissociate identity disorder individual’s alter. 

Reason of dissociative identity disorder individual's alter 

There are several reasons for DIDs alter: when a person does not know how to deal with their traumatic past and uses dissociation as a coping mechanism. Disassociation acts as a defense mechanism that protects the child from thinking and feeling the past and remains in fantasy. When an intense traumatic experience occurs, it affects brain chemistry, which ultimately affects memory. The brain's neurochemicals are released in such large amounts that they influence the area of the brain responsible for memory. Depending on their individual brain chemistry, some human beings may be better able to dissociate than others. 

Types of dissociative identity disorder

  • Dissociative Amnesia 

When a person blocks out certain information, it is usually associated with a stressful or traumatic event. This includes loss of memory for a long period of time. 

  • Dissociative Fugue 

The person temporarily loses his or her personal identity. People with dissociative fugue often become confused about who they are and may even create new identities. People with this disorder show no signs of illness, such as strange appearances or behaviors. 

  • Depersonalization Disorder 

In this condition, a person feels a sense of being disconnected or detached from his or her body. The disorder is sometimes described as being numb or in a dream, or feeling like you are watching yourself from outside your body. 

  • Identity Confusion 

In this condition, an individual feels uncertain about who they are. A person may feel as if there is a struggle within him to define himself. 

Diagnosis

People with multiple personality disorders are diagnosed between the ages of 20 and 40. It can also be diagnosed by switching between two or more personality states, i.e., alters. Dissociative boundaries between the alters occur frequently. 

Treatment 

The most common treatments for DID or MPD include psychotherapy, family therapy, cognitive therapy, medication, and hypnosis. The treatment of dissociative personality disorder lasts an average of 4 years. 

  • Psychotherapy 

Psychotherapy is the main treatment for dissociative disorders or MPD using the psychological method, with the goal of deconstructing the different personalities and uniting them into one. It is long-term usually twice a week. 

  • Family therapy 

To educate the family about DID and its causes, to understand the changes that can take place as the personality is being reintegrated, as well as educate the family on how to cooperate and treat the individual. 

  • Cognitive therapy

This type of therapy focuses on changing dysfunctional thinking patterns. 

  • Medication 

The most commonly prescribed medication is tranquillizers or antidepressant drugs because their altered personalities may have anxiety or mood disorders. 

  • Hypnosis

Hypnosis is a state of human consciousness involving focused attention, reduced peripheral awareness, and enhanced capacity for response to suggestion. Under hypnosis, the multiple personalities slowly reveal themselves, and since people in this state are highly receptive, the personalities can be integrated to form one single personality.
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Protein Synthesis | Transcription phase | Translation phase |

Protein Synthesis

The cell preserves hereditary information in genes, which work as instructions for building proteins. The gene instructions from the DNA transfer are stored in the molecules of ribonucleic acid, the "mRNA," and then the mRNA transcript translates the instructions for the synthesis of protein. This one flow of hereditary information from DNA to mRNA and from mRNA to protein is known as the "center dogma of life."

There are three different forms of RNA in cells, each of which has a different function: messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). All three types of RNAs are essential for protein synthesis. The process of protein synthesis involves two stages known as transcription and translation. The process of transcription and translation is discussed below.

mRNA Transcription 

Transcription involves the transfer of information from a gene in DNA into an mRNA molecule. In eukaryotic organisms, transcription occurs inside the nucleus, while in prokaryotic organisms, it takes place in the cytoplasm. It is defined as

"The formation of RNA on a template of a DNA strand is called transcription."

Transcription includes the following steps:

Template binding

Transcription begins when an enzyme called RNA polymerase binds to the transcription start site of a gene on a region of DNA called a promoter. A promoter is a specific sequence of DNA that is important for the recognition of RNA polymerase, known as the transcription start site. It is known as the "TATA box" in eukaryotes because it is rich in thymine and adenine nitrogenous bases. RNA polymerase cannot initiate transcription on its own until the transcription factors recognize the sequence and help the RNA polymerase in their search for promoters to start the transcription. After RNA polymerase binds to a promoter, the enzyme starts to unwind and separate the two strands of the double helix, exposing the DNA's nitrogen-containing bases. The enzyme recognizes the nitrogen base and adds the complementary base on the growing chain, the two bases join each other by a phosphodiester bond and initiate the formation of the mRNA chain. DNA bases act as a template for the formation of the mRNA molecule. In any particular transcription, however, only one of the two strands of DNA is transcribed; this strand is called the template strand or antisense strand, while the opposite strand is called the coding sense or sense strand. Thus, the resulting mRNA is complementary to the DNA template from which it is formed.

Chain elongation

RNA polymerase separates apart the double helix and moves downstream along the DNA template strand from the initiation site, always in the 3’ to 5’ direction. While the growing mRNA always synthesize from 5’ to 3’ direction. The enzyme reads each nucleotide and adds it on complementary mRNA. When the RNA nucleotides are added, they are linked together with sugar-to-phosphate covalent bonds. In eukaryotic cells, the RNA nucleotides are found in the nucleus; in prokaryotic cells, they are in the cytoplasm. As the transcription grows downstream, the two strands of DNA close up by forming hydrogen bonds between complementary bases and reform the double helix.

Chain termination

RNA polymerase continues to elongate the mRNA until it reaches the termination site. It is the specific sequence of nucleotides that signals the termination or end of the mRNA transcription. The mRNA, the transcript of a gene, is released, and polymerase subsequently dissociates from the DNA.

In prokaryotes, the mRNA is directly released into the cytoplasm, where it is translated into protein. In eukaryotes, mRNA has to travel a long distance from the nucleus to the cytoplasm; therefore, mRNA must be processed before it is released.

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Figure 1: Labeled diagram of transcription. 

mRNA processing in eukaryotes

Before being released into the cytoplasm for protein synthesis, eukaryotic mRNA undergoes post-transcriptional modification, which includes 5' capping, mRNA splicing, and polyadenylation.

Addition  of 5 ’capping on mRNA:  

Before the release enzyme called guanyl transferase adds the cap, it is in the form of 7-methyl GTP (7-methyle-guanosine-5'-triphosphate) on the first nucleotide of mRNA at 5’. It is a highly methylated modified guanine base. The 5’ cap protects the mRNA from degradation, prevents it from being attacked by exonucleases, and even assists other post transcriptional events, including splicing, polyadenylation, and recruitment of translational machinery.

mRNA splicing

The growing mRNA stretch contain both intron (a noncoding region) and exon (a coding region), and the pre-mRNA undergoes alternative splicing, which leads to different combinations of mRNA before release. The different mRNAs produce different proteins.

Polyadenylation

The tail is in the form of poly A linked to 3’ end of mRNA by the help of an enzyme called poly-A polymerases. Poly-A tail is in fact a stretch of adenosine monophosphate, which contains almost 100 to 250 nucleotide residues. The newly synthesized mRNA contains a 3’ UTR region that is enriched with AU nucleotides; the 3’ UTR contains a sequence AAUAAA that assists the addition of a tail. The end 3’ region is cleaved by a set of proteins to cleave the hydroxyl group, and the enzyme poly-A polymerases assist in the addition of the poly-A tail. The tail protects the mRNA from a variety of cytoplasmic enzymes, stabilises the mRNA, prevents it from degradation, and allows the export of mature mRNA from the nucleus to the cytoplasm.

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Figure 2: Structure of mature mRNA.


Translation

The equipment for translation is located in the cytoplasm, where a cell keeps its protein supply. This translation machinery includes: transfer RNA (tRNA), which is a single strand of RNA folded into a compact shape with three loops, one of the loop has a three-nucleotide sequence called an anticodon. A codon can be complementary to one of the 64 codons of the genetic code. Opposite the anticodon on a tRNA molecule is a site at which the molecule carries an amino acid. The ribosome is composed of protein and rRNA; each ribosome has two subunits. The smaller subunit binds to the mRNA, and the larger subunit has three functional sites. Two sites called P and A bind to the tRNA, while the third site catalyzes the formation of peptide bonds between amino acids in growing protein chain.

tRNA and genetic code

In the presence of an enzyme called aminoacyl-tRNA synthetases, each tRNA is chemically linked with a specific amino acid. The tRNA is covalently linked with the specific amino acid, and ATP provides the energy for the binding reaction. There are different types of tRNA, ranging from 40 to 60, depending on the type of cell and species, each bearing the specific anticodon for the 20 different amino acids floating in the cytoplasm. There are 64 different codons; multiple codons can be encoded for the same amino acid. AUG on an mRNA read is a start codon and always encodes for methionine; similarly, UAA, UAG, and UGA are stop codons and do not encode for any amino acid.

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Figure 3: Genetic codes for particular amino acids. 
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Figure 4: Labeled diagram of structure of tRNA.


Translation definition

"Translation is the process by which a protein is synthesized; the liner amino acid sequence is directed by mRNA sequences that are specified by a gene."

The mechanism of translation The process consists of the following stages.

Translation Initiation

Translation begins when mRNA binds to the smaller ribosomal subunit in the cytoplasm. The ribosomal S1 protein plays an important role in the recognition of mRNA and its binding. Similarly, the ribosome also recognizes the 7-methyle-guanosine cap and scans the 5’ UTR (untranslated region) for binding and initiation of translation. The mRNA is oriented in such a way that the start codon (a codon that signals the beginning of a protein chain) is sitting in the P site, and at the same time, the initiator tRNA with the anticodon UAC base pairs with the initiation codon AUG bearing the amino acid methionine (met) and initiates the complex. The larger ribosomal subunit joins the initiation complex, and a protein called initiator factor brings these translation components together. In a bacterial cell, almost 3 initiator factors (IF1, IF2, and IF3) are required to initiate the translation, while in eukaryotes, which are complex organisms, there are a number of initiator factors, but at least 11 are required to initiate the translation (eIF2, eIF3, eIF1, eIF1A, eIF4A, eIF4F, eIF4G, eIF4B, eIF5 and eIF5B, eIF5 and eIF2B, respectively). GTP, which is closely related to ATP, provides energy for the initiation process. The larger subunit has three sites: the P (peptidyl) site, the A (aminoacyl) site, and the E (exit) site. The initiator tRNA first binds to the P site, which later holds the nascent peptide chain, and the A site is available for the tRNA (aminoacylated) bearing the next amino acid. The E site holds the deacylated tRNA before the tRNA leaves the complex after the transfer of amino acid.

Translation Initiation Mechanism:

  • The initiation phase of translation begins when initiation factors (eIF1, eIF3, and eIF1A) bind to the smaller ribosomal units, while initiation factor eIF2 along with GTP complexes with initiator tRNA brings it to the ribosome, and a group of eIF4 initiation factors brings mRNA to the ribosome.
  • As the translation machinery was brought to the ribosome, the ribosome then scanned the mRNA downstream to identify the initiation codon AUG. This process required energy, which was provided by ATP hydrolysis.
  • As the start codon was identified, another initiation factor known as eIF5 triggered the GTP hydrolysis, as a result, the eIF2_GTP complex dissociates and tRNA is released and binds to the A site.
  • The larger subunit then binds to the complex and continues the process.
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Figure 5: Mechanism of translation initiation.

The elongation cycle of translation

After the formation of the initiation complex, the very next step is elongation of the peptide chain. As the incoming aminoacylated tRNA binds to the codon at the P site, the elongation factor and GTP are required for the process. The amino acid at P site forms a covalent link with the amino acid at A site, and a peptide is formed between the new amino acid and the growing polypeptide chain. The reaction of peptide bond formation is catalysed by peptidyl transferase (a catalytic RNA). The growing peptide chain first transferred to the tRNA at A site. The ribosome moves along the mRNA downstream from 5’ to 3’. As the ribosome translocates downstream, there is a shift of one codon forward. The initiator tRNA or tRNA at P site shifted to the E site and the tRNA bearing the polypeptide chain translocated at P site, A site is again available for the next coming tRNA.

Mechanism of chain elongation

The following are the steps involved in chain elongation:

  • The elongation phase of translation involves the elongation of polypeptide chains, as the initiator methyonyl tRNA sits at the P site and the second aminoacyl tRNA is brought to the A site by the elongation factor EF-Tu complex with GTP, having an anticodon matched exactly to the code at the A site.
  • GTP hydrolysis the bond, and GTP_EF-Tu complex leaves the ribosome and newly coming aminoacylated tRNA sits at A site.
  • A peptide bond is formed between two amino acids, which results in the transfer of methionine (an amino acid at the P site) to the amino acid at the A site.
  • After the transfer, the ribosome is translocated three nucleotides forward; this process is conducted by the elongation factor EF-Gu.
  • As the ribosome translocate the deaminoacylated tRNA shifts at E site, the tRNA at A site bearing the peptide chain shifts at P site and A site sets free for incoming new aminoacylated tRNA.
  • The process is to continue until the whole mRNA is fully decoded and reaches to the end.
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Figure 6: Mechanism of translation elogation.

Termination of translation

When a ribosome reaches a termination codon on a strand of mRNA, a protein called release factor recognizes the stop codon and binds to the A site instead of tRNA. In eukaryotes, a single release factor, eRF1, recognizes all three stop codons, whereas prokaryotes have two release factors.RF1: It can recognize UGA and UUA, and RF2: It can recognize UUA and UGA. The release factor hydrolyzes the bond between the tRNA in the P-site and the last amino acid of the polypeptide chain. Both polypeptide and tRNA are then free to depart from the ribosome, and the two ribosomal units dissociate from the mRNA, and that’s how the translation ends and the process of protein synthesis is completed. However, one mRNA can be translated by several ribosomes at the same time.

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Figure 7: Mechanism of translation termination.


Post translational modification

Protein could not be synthesize or fully functional soon after the translation. As the translation ends, the nascent polypeptide chain undergoes posttranslational modification. These modifications include the removal of Met from certain proteins and the addition of functional groups that include methyl, phosphate, acetate, and amide. Lipids and sugar are also added to certain proteins. Other proteins undergo conformational changes, breakage of some bonds, formation of new covalent linkages, excision of some peptide chains, and reorientation of peptide chains. All these posttranslational changes lead to the final protein product, which is then available to perform its function.

Sources

Clark, D. P., & Pazdernik, N. (2012). Molecular biology. Elsevier
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c-Myc| gene and protein structures| function| mutation

What is c-myc Gene Family 

MYC is a family of regulator gene and proto-oncogene that encode a protein which regulate the expression of other gene in an estimation it regulate nearly 15 % the expression of other gene and basically involved in cell   proliferation, cell growth, apoptosis and cell transformation. Infect they determine the fate of a cell. MYC gene family include other member like c-Myc (c-MYC), l-Myc (I-MYC), and n-Myc  (n-MYC). C-Myc is firstly discovered and referred as MYC.

c-myc

c-myc was discovered in human Burkitt's lymphoma, which show homologue to viral oncogene v-Myc which was isolated from an avian retrovirus. c-myc gene is located at chromosome no 8 at position 8q24.21, which encode the c-myc protein with in the nucleus which regulate the expression of other gene, in two ways.

  • Firstly, these proteins act as transcription factors for other gene.
  • Secondly these proteins act as histone modifier which help in transcription of a gene.

The encoded protein implicated in various cellular process like cell growth, proliferation, loss of differentiation and apoptosis.

Structure of c-myc gene and protein 

The structure of c-myc gene consist of three exons and two introns, more over the c-Myc transcription is regulated by multiple promoters. 

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Figure 1: represents the structure and location of c-myc gene.

c-Myc protein is a 65 kDa nuclear phosphoro-protein, the basic structure of the protein consists of basic helix-loop-helix domain and leucine zipper (bHLH/LZ), bHLH is a DNA binding domain while LZ is bind with other protein (MAX).

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Figure 3: represents secondary c-Myc protein structure.

Mechanism of c-MYC Ativation

The function of c-MYC is mediated by another protein that is Max, c-MYC when binds to the Max and generated a complex called Myc-Max complexes. This Myc-Max complexes releases the different type of transcription factors which regulate the expression of other gene that involve in cell proliferation, growth, apoptosis etc. Similarly, this Myc-Max complexes mechanism is controlled and inhibit by other factors to regulate the process.

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Figure 3: represents Myc-Max complexe and their binding to DNA.

Function of c-myc Gene

c- myc gene involve in many function

  • The primary functions of c-Myc are to promote cell proliferation and to arrest cell differentiation
  • Have role in the regulation of stem cell function. With the cooperation of n-Myc, c-Myc inhibits the differentiation of stem cells, such as embryonic stem cells 
  • c-Myc is not only an inducer of cell proliferation, but also has the ability to regulate cell apoptosis via various signaling pathways.
  • Many observations suggested that protein synthesis is regulated by c-Myc in multiple ways, in which the transcription of various RNA, iRNA, and ribosomes is controlled by the oncogene product.
  • Recently, evidence has been accumulating that c-Myc also regulates the expression of miRNAs, which are a set of small, non-protein-coding RNAs and regulate gene expression at the post-transcriptional level.


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Gene/Protein Structure of C-Repeat binding Transcription Factor

Table of content 

Gene/Protein Structure of C- Repeat Binding Transcription Factor

CBF Gene family

CBF (C-repeat bindingfactor) also known  as DREB (dehydration-responsive element-binding protein). DREB is the class of transcription factors in plants that induces under stress stimuli, and involve in the regulation of series of cascade for the activation of stress responsive gene to bring tolerance in plants.

The CBF (CBF1, CBF2, and CBF3) genes in Arabidopsis organize in tandem on chromosome 4. Both CBF1 and CBF2 induced by cold, while CBF4 involved in drought resistance. It is difficult to determine the chromosomal location for a gene in plant of complex genome and where there high variation in chromosomal ploidy and aneuploidy level like sugarcane. However in a recent study about 110 SsDREB subfamily proteins identified in S. spontaneum. Which were classified into six groups, the number of identified protein is also greater than other species. The SsDREB genes variably distributed across all 29 chromosomes of S. spontaneum, while chromosome 2B contain the greater number of DREB genes.

The first cDNA of CBF1 (C-repeat/DREB Factor 1) was isolated from Arabidopsis thaliana in 1997 by Stockinger and colleague. Molecular mass of the protein is about 24 KDa, comprises of nuclear localization domain and acidic activation domain.  All AP2/ERF family members have conserved AP2 DNA-binding motif that is compose of ~ 60 amino acids residue.  AP2 DNA-binding domain recognize and bind to specific sequence of cis-regulatory elements present in promoters of many stress responsive gene  The AP2 domain further possess two regions: 1)-YRG region/element that consists 20 amino acids, it is present in N-terminal stretch and is rich with hydrophobic and basic amino acids, responsible for DNA-binding activities. 2)-The RAYD region/element contains 40 amino acids. At RAYD region about 18-amino-acid stretch is present at C-terminal and is responsible for amphipathic alpha helix formation, that involve in protein–protein interaction. Three-dimensional analysis by using nuclear magnetic resonance (NMR) of AP2/ERF motif/domain revealed a β-sheets having three strands that connected anti-parallel way by α-helix and loops. Similarly, at AP2/ERF domain's end the DSAW motif is present and at the C-terminal region end LWSY motif is present. However nuclear localization signal (NLS) involved in entrance of DREB proteins in nucleus, it is a stretch rich of basic-amino acid residues. Those TF proteins without the presence of NLSs enter the nucleus by protein–protein interaction with the help of TFs that have NLSs. In AP2/ERF protein domain at position 19 the glutamic acid and at position 14 amino acid Valine are quite conserved but, some species amino acid at 19 is replace by valine .

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Representation of typical structure of CBF/DREB protein domain.

Function of DREBs/CBF (C-repeat binding factor)

The DREBs/CBF (C-repeat binding factor), belongs to ERF subfamily and play a key role in plants in response to stress stimuli. The DREB/CBF gene are mainly involved in expression of cold stress-responsive genes. Along with cold stress DREB greatly express under other abiotic stress like drought, salinity in ABA dependently and ABA independently. CBF family further includes three members namely DREB1a/CBF3, DREB1b/CBF1, and DREB1c/CBF2 that induce gene transcription of Cold-regulated genes (COR) under cold stress. The CBF TFs recognized and bind to the conserved CRT/DRE motif CCGAC present in the promoters of many cold-regulated (COR) genes which mediate plant freezing tolerance. In sugarcane CBF/DREB greatly expresses under drought and cold stresses and mediate wide range of COR gene that confer tolerance in many plant. Currently several inducer of CBF have been identified which includes MYB, Inducer of CBF expression (ICE1 and ICE2), Ethylene insensitive (EIN3), Calmodulin-binding transcription activator (CAMTA1, CAMTA2, CAMTA3), Phyto-chrome-interacting (PIF3/4/7) factors, Suppressor of overexpression of co1 (SOC1) and others. Which regulate the expression of CBF and continue the cold signaling pathway. Nevertheless ICE1-CBF-COR best known signaling cascade involve plants in cold tolerance responses.

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Low temperature CBFs activation, CBFs bind to CRT/DRE cis-acting element, present in promoter of COR gene, activation of whole signaling cascade results in an increase freezing tolerance.




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What is Molecular Chaperon or Ubiquitious Protein?

Table of contents 

Chaperon and Ubiquitination's Role in Protein Conformation or Function 

What is Molecular Chaperone?

Molecular chaperones are the class of proteins that assist in stabilising non-native protein (the biologically relevant components of a cell but are misfolded proteins) conformations and promote folding into the native state whenever possible. Alternatively, misfolded proteins are eliminated by a cell via a degradation mechanism called the ubiquitin–proteasome system.
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What is Protein folding?

Protein synthesis is carried out by ribosomes. In the beginning, ribosomes synthesise a linear chain of amino acids called the polypeptide chain. The stretch of mRNA specifies the amino acid sequence, and each amino acid in this polypeptide chain has its own unique property. For example, glycine is very hydrophobic, while arginine is very hydrophilic. These properties of amino acids depict the three-dimensional structure of the protein. The outside of the protein possesses the hydrophilic amino acids, while the inside of the protein must conserve the hydrophobic amino acids. The secondary structure of proteins (alpha helices and beta sheets) is acquired by hydrogen bonds between the polypeptide chains. After the primary and secondary structures, the helices constitute the tertiary structure. Protein folding must be precise in its three-dimensional form and must not be aggregated or degraded. The unfolded and misfolded proteins result in non-native protein aggregation, which is an inactive form but, in some cases, may lead to diseases. 

The Role of Molecular Chaperones and Ubiquitination in Protein Conformation 

In molecular biology, the chaperones are defined as "the molecular chaperones are the proteins that have the ability to assist and stabilise the conformation of non-native folding. The ubiquitous proteins, which are an amazingly diverse family of proteins, are also among the most abundant intracellular proteins. The basic function of chaperones is posttranslational modification of proteins, so ubiquitous proteins mediate correct protein folding, inhibit misfolding, and prevent other proteins from degradation and non-native aggregation during their tertiary structure formation. Chaperones sometimes interact with other packaging called ancillary proteins. Both proteins together regulate the folding of other proteins. Chaperones are ubiquitously expressed and are found in all cellular compartments of the eukaryotic cell (except for peroxisomes). In general, the concentration of chaperone increases in response to diverse stresses in order to prevent the proteins' folding and for the stabilisation of the protein. An example of chaperon proteins are the "heat shock proteins" (Hsps), which are discovered in bacteria under stress conditions. The bacteria produce a number of such proteins under stressful conditions, such as higher temperatures, pH variation, and hypoxic conditions. 

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Fig 2: Role of Chaperon in quality control of protein.

Two examples of Hsps are Hsp70 and Hsp60. 

Heat shock protein (Hsp70)

The Hsp70 chaperone proteins are folding catalysts that help in the refolding or misfolding of aggregated proteins and in the folding and assembling of new proteins. The Hsps 70 contains two different domains, namely the N terminal and the C terminal. The N terminal contains the ATPase site while the C terminal domain binds to the substrate. The N terminal ATPase hydrolysis site helps the C terminal to open and bind to the substrate. 
Hsp70 recognises the "extended region" of an unfolded polypeptide chain. This extended region contains many hydrophobic residues. HSP70-binding prevents the aggregation of these proteins. 
Fig 3: Domain organization and 3D structure of Hsp70

Heat shock protein (Hsp60)

Hsp60 chaperone proteins bind to exposed hydrophobic residues of unfolded proteins and help to form aggregates that are stable but inactive. Hsp60 proteins could not prevent a protein's aggregation, but rather they functioned to isolate and quarantine an unfolded protein. This isolation prevents a polypeptide chain from aggregating into clumps with other chains within the cytoplasm.
Hsp 60 contains 14 different protein components. These proteins are made of 7 proteins which are placed on top of each other and form two rings. Unfolded proteins can then fold safely within these rings because the Hsp60 protein does not interfere with the unfolded protein (newly formed proteins) or aggregate with other unfolded proteins. Hsp60 also has two different domains: the protein binding motif, where ATP binds, and the unfolded proteins can enter the hole between the two rings. The enclosed state, called the folding-active state, is then activated by ATP hydrolysis. This conformational change prevents the unfolded protein from leaving the ring and assists the protein folding. The state lasts for around 15 seconds and the folded protein  after proper folding, is released into the cytoplasm. The enclosed state then deactivates and the protein changes back to its conformation.

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Fig 4: Domain organization and 3D structure of Hsp60.
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Anorexia nervosa| symptoms, causes, risk factors and treatment|

 Anorexia nervosa

Anorexia nervosa is an eating disorder and a serious mental health condition accompanied by a loss of appetite due to the fear of becoming obese. Anorexic people intentionally try to keep their body weight low by restricting food intake and exercising excessively due to the fear of becoming obese. Even though their body weight drops to a dangerous level. The patient often has a distorted image of their body; emotional challenges; and constant starvation may lead to other problems and diseases like osteoporosis, low blood pressure, cessation of menstruation, constipation, and others. 

Prevealance 

Both sexes can be affected by anorexia nervosa. However, such feelings largely affect girls just after the onset of puberty, between the ages of 12 to 21 years. These girls are often immature psychologically and unable to cope with the challenges of puberty and their emerging sexuality. The loss of feminine characteristics enables the girls to retreat into a child-like state in which they feel safe. 
Females outnumber males by a factor of ten. Though it is more common in females, its effects are more life-threatening in males as compared to females due to the mistaken belief that men are not affected by anorexia. 
It also more often affects models, as the fashion industry encourages the behaviour of restricting food or skipping meals, which may lead to severe emotional and mental health issues. 

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Symptoms 

Anorexia nervosa is an eating disorder characterised by the starvation of the body, which may lead to a significant loss in body weight and body mass. Food deprivation and malnutrition may lead to serious Physical, emotional, psychological, and physiological symptoms include the following: 

  • Physical symptoms 

  • Lose of a normal body mass index for one's age and height. 
  • The cessation of the menstrual cycle occurs due to prolonged weight loss. 
  • Malnutrition may lead to dry hair and skin as well as hair thinning, swollen hands and feet, discoloration of the skin, particularly the feet, and infertility. 
  • Loss of muscle mass at an extreme level causes fatigue and muscle pain. 

  • Physiological symptoms 

Continuous loss in body mass, weight loss, and malnutrition may also affect body function. The physiological symptoms include: 
  • Constant starvation, which may cause low blood pressure.
  • Bloating or an upset stomach could occur. Abdominal distension.
  • Loss in normal body temperature along with cold hands and feet and intolerance to cold. 
  • Bad breath and food deprivation may be the effects of ketoacidosis. 

  • Emotional and behavioural symptoms 

Anorexic person can be demonstrated by their emotional and behavioural acts. 
  • Self-induced vomiting in order to get rid of food 
  • Anorexics also take drugs or pills and laxatives to flush out the food. 
  • Exercising excessively even when the body is too weak.
  • They isolate themselves from events, family members, and the public. 
  • They frequently lie about the food they have consumed. 
  • Always eating selectively
  • Avoid eating around other people. 
  • Self-esteem loss
  • Performing food rituals like eating food on their own terms and arranging and cutting it in their own order. 

  • Psychological symptoms 

Food deprivation may lead to severe psychological issues. 
  • Depression 
  • Insomnia 
  • Admire and idealise the thinner body.
  • Mood swing 
  • Self-harming thoughts and acts
  • The perception that their body is over-weighted.
  • Their ideal body representation is altered. 
  • Continually checking the mirror and perceiving the flaws. 
  • Even after extreme hunger, denying to eat and laying of hunger.

Causes and risk factors for anorexia nervosa 

Anorexia nervosa can be caused by several factors. It can be psychological, environmental, or genetic.

  • Environmental factors 

The environment can influence a person's psychology and behaviour greatly. Early research suggests that eating disorders may be caused by environmental factors such as: 
  • Criticism in one's life about their body weight, shape, and eating habits.
  • Continues pressure to fit into a body or shape from society, culture, relationships, family, or peers. 
  • Past life trauma and racism.
  • A person who has faced bullying about their weight or body shape may develop anorexia. 
  • An obsessive personality or a sense of perfectionism could be a factor. 

  • Genetic factors 

Genetics could be a possible risk factor for causing anorexia nervosa. Although the exact gene for anorexia has not been discovered, it could be by following: 
  • Anorexia nervosa can run in families; those who have an eating disorder can be at great risk of getting the disease. 
  • In a research study, two gene have been discovered  ESRRA and HDAC4,  can cause eating disorders in an individual and be a risk factor for the disease. 

  • Biological factors 

Biological dysfunctionalities and dysregulations of certain biological functions in the human body can cause disease. For example, 
  • Brain and hormonal changes during puberty can be associated with anorexia nervosa. 
  • Dysfunctional of the neuroendocrine hormonal system that signals between the brain and the digestive system and controls hunger. 
  • Dysregulations of the brain’s neurochemicals like serotonin, dopamine, and norepinephrine disturb biological pathways that regulate the hunger and appetite of an individual. 

Anorexia Risk Factors 

Prolonged anorexia causes several complications in the body, which may lead to severe health problems and may cause serious health issues and diseases.
  • It can cause malnutrition, which may lead to several diseases like gastro-intestinal disease, constipation, heartburn, liver problems, nausea,  cyclic vomiting syndrome. 
  • Kidney problems like distal renal tubular acidosis, in which the kidney is unable to remove acid from the blood.
  • Heart problems like heart failure, slow heart beats Anemia, which is caused by the deficiency of RBSs.
  • Decrease in bone mass, osteoporosis, calcium deficiency, vitamin K deficiency. 
  • Hormonal problems reduce the level of oestrogen in females and testosterone in males. 
  • It also have effects on fertility. 
  • Muscle weakness, pain, fatigue, and tiredness 
  • Skin problems like sarcoidosis (patches on the skin), dry skin, and loss of hair.
  • It can lead to mental health problems like OCD, depression, anxiety, suicidal attempts, and serious self-injury.

Treatment 

Anorexic people's treatment is based on how long the individual is affected by the disease and how much the individual is affected by other complications. Psychiatric therapy is the best way to cure the disease. No other such medication has been found yet to cure the disease. However, antidepressants are given to treat mental health problems like depression. 

Psychiatric therapy 

Psychiatric therapy is suitable to treat patients. It includes:

  • Cognitive-behavioral therapy (CBT):  It is therapy based on weekly sessions for up to 40 weeks (9 to 10 months) done by the practitioner with the aim of helping the person to feel good around food, develop eating habits and new ways of thinking, behaving, and managing stress. 
  • Maudsley Anorexia Nervosa Treatment for Adults (MANTRA): It is a therapeutic treatment for adults. It includes 20 sessions; the first 10 are regular on a weekly basis; the other 10 are flexible based on the available time you have. The aim is to realise the individual's causes of anorexia and change their behaviour patterns towards food. It also includes family for cure and fast recovery. 
  • Specialist Supportive Clinical Management (SSCM): It includes 20 sessions conducted by the practitioner with the main aim of exploring the causes of the problems that were the cause of the disease. To know the importance of nutrition and how it helps in gaining weight It also focuses on helping the patients come back to a normal routine, whether at work, school, etc. 

Heath complications 

The health issues can be treated by medication and hospitalisation of the anorexic person.

 Sources

Treasure, J. (2013). Anorexia nervosa: A survival guide for families, friends and sufferers. Psychology Press.
Watson, H. J., Yilmaz, Z., & Thornton, L. M. (2019). Hü bel CA, Coleman JR, Gaspar HA et al. Genome-wide association study identifies eight risk loci and implicates metabo-psychiatric origins for anorexia nervosa. Nat Genet, 51, 1207-1214.


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How to Make Hair Longer, Denser, and Shinier?

How to Make Hair Longer, Denser, and Shinier? | Hair Care Tips | Best Oil for Hair | Home Remedies for Hair Care | Food and Supplements for Hair Growth and Care |

Hair care is not a fast and easy process. Hair growth takes time, and most often, for most people, there is a period of shedding of weak, dead hair before experiencing regrowth and density. Although genetics play a major role in your hair type, your environment also greatly affects the growth and density of your hair.
Following are the tips for better hair health, volume, and growth:
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Tips for hair care or elements that affect the hair growth and volume

Use of a hair mask

Hair masks can help moisturize and nourish your hair. They're substantially beneficial for damaged, dry, or frizzy hair. Choosing the right hair mask will depend a lot on individual hair texture and type.

Massaging the hair in the shower

Massage the hair and your scalp every day to enhance the blood circulation and help clean your scalp by removing oil and buildup. Make sure to do it gently; do not rub vigorously.

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How does hormonal imbalance effects hair?

Hormonal imbalances can cause baldness when the levels of oestrogen and progesterone reduce. The hair grows more slowly and thinner. A decrease in such a hormone also triggers an increase in the production of androgen. Androgen shrinks hair follicles, resulting in hair loss on the head.

Diet and its effects on hair

Avoid diets that restrict calories too severely.  Add a variety of hair proteins to help improve the production of amino acids needed for keratin production. Eat plenty of whole-grain fruits and vegetables.

Stress and hair fall

Stress and hair loss are related. Significant stress pushes a large number of hair follicles into the resting phase. Learn and practise stress-relieving techniques such as deep breathing, yoga, and meditation regularly. Get regular exercise, which helps manage stress and its effects. Spend time with positive people.

Avoid using the wrong hair product

Using the wrong product is causing the hair loss. Avoid the hair shampoo, conditioner, and treatments that contain sodium lauryl sulphate at all costs. SLS is a chemical that works as a detergent.

Hair style and baldness

Certain hair styles also damage the hair's strength. Wearing stretchy hairstyles, like a slicked-back ponytail, on a regular basis causes hair breakage. It is also important to brush wet hair carefully because it can cause more damage to wet hair.

Hot water and heat protection products for hair

Regularly using hot water on your hair can make it brittle and porous, which leads to extensive breakage and hair fall. Moreover, hot water opens up the skin pores, which can make your hair roots weaker, further aggravating hair fall.
Using a heat tool without using a hair protection product When you expose your hair to heat every time you style your hair without using hair protection, it can lead to hair damage. Heat can dry out your strands, cause split ends and breakage, and make your hair dull and dry, among other issues.
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Effect of rubbing hair

Rubbing wet hair with a towel vigorously can lead to excessive hair breakage and hair fall. Towels with thick, absorbent fibres can do more harm than good. The hair becomes more frizzy and tangled as the towel ruffles up the cuticle of the hair.

Alopecia

The immune system mistakenly attacks hair follicles, causing inflammation. Vitamin D deficiency can be an important factor in the etiopathogenesis of alopecia.

Home remedies and hair oils

Home remedies for hair growth greatly affect hair growth and density. Castor oil, rosemary oil, olive oil, aloe vera, fenugreek seed, flex seed, and egg are some essentials that are often applied to hair and tremendously benefit the hair. Homemade hair oil and a hair mask are also good for hair. The following are home remedies and homemade oil for hair.

How does oiling the hair affect it?

Oiling has a direct effect on the health of the hair; it helps nourish the scalp, promote blood circulation, and increase hair thickness and density. There are a number of types of hair oils that can be used differently for hair care.

Almond oil

Almond oil promotes hair health, retains moisture, and is good for skin and hair health.

Coconut oil 

Coconut oil is definitely good for growth, density, and making hair longer. It contains vitamin E and fatty acids that nourish the scalp and penetrate the hair cuticle.

Caster oil

Castor oil is a rich source of vitamins E and minerals; it promotes hair growth and is best for hair strength, but don’t use it directly; always use it with carrier oil.

Rosemary oil 

It is known that rosemary has been used by many to promote hair growth. Make rosemary oil by adding essential oils for hair health.

Amla oil

Amla oil is loaded with vitamins C and E; it is also a good source of antioxidants; it prevents bacterial infection; and it promotes growth and thickness.

Onion oil 

It is rich in antibacterial and antioxidant properties that keep your scalp healthy and free from infection. Make your own onion oil by adding other essentials like fenugreek seed and black seed and by adding suitable oils like caster, almond, or coconut for hair care.
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Home remedies and a hair mask

For growth and frizzy hair

Applying 1 cup of yoghurt with 2 tablespoons of coconut oil and 2 tablespoons of aloe vera gel twice a week for 1 hour helps promote hair growth and makes it shiny and frizz-free.
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For hair volume, increase

If you have thin hair, add 2 tablespoons of aloe gel, 3 tablespoons of onion juice, and 3 tablespoons of coconut oil. Massage gently to increase blood circulation and leave it for an hour.

Hair mask for shiny hair

Chop 7 to 10 okra (ladyfingers), boil them for 10 to 15 minutes, let them cool, apply them for an hour, and rinse with mild shampoo. This will make your hair shiny and silky.

Rice water good for hair

Soak the cup of rice in water for 24 hours and spray it on your hair, or boil the rice along with onions and fenugreek seeds, strain it in a container, and apply it for an hour on your hair. This is the best formula for hair growth and will regrow your lost hair.

Food and nutrients that enhance hair growth

The nutrients that are essential for hair growth and density include biotin, zinc, iron, essential fatty acids, folates, vitamin A, vitamin C, and vitamin E. Protein improves overall growth and density, is healthy, and reduces hair fall.

Food that is good for hair

Your hair care relies only on outside appliances. The nourishment and growth of the hair are also affected by the foods that have been taken, so always eat good-quality food for hair growth. Following are the important foods that provide different nutrition for hair.

Yogurt

It helps with hair growth because it contains protein, the building block of your locks. Yogurt also has an ingredient that helps with blood flow to your scalp and hair growth.

Spinach

Green leafy vegetables like spinach are rich sources of nutrients. It has vitamins A and C, iron, folates, and beta-carotene. It helps in hair growth, keeps the scalp healthy, moisturises the hair, and cures brittle hair.

Iron-Fortified Cereal

< span style= "font-family: georgia;">In fact, an iron deficiency in the body leads to hair loss. When a body is low on iron, oxygen, and other nutrients and they are not getting transported to the body, it may also affect the hair follicles. Consume iron-fortified foods like cereal, grains, soybeans, and lentils, which can prevent the hair

Sweet potatoes

Sweet potatoes cure dry and dull hair, as they are loaded with antioxidants like beta-carotene. Beta-carotene is converted into vitamin A by the body. Vitamin A moisturises the hair and makes it shiny and silky.

Eggs 

Eggs in your diet are a rich source of protein, biotin, vitamin B, and iron, which helps in hair growth, strengthens the nails, and is good for the skin.

Citrus Fruits 

Citrus fruits are a good source of Vitamin C. Vitamin C in the diet is required for the absorption of iron. Consumption of citrus fruits more often in the diet strengthens the hair.

Nuts and Seeds for Omega-3 Fatty Acids

Nuts and seeds in your diet are loaded with omega-3 fatty acids that nourish the hair and promote density. You more often consume walnuts, almonds, chia seeds, pumpkin seeds, and flex seeds for hair growth and care.

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