Cycle 11: Epigenetics Flashcards
what is the charge of DNA
negative because of the phosphate backbone
what charges are histones
positives cuz of lyzine
what do histones do
they are proteins that package and organize DNA
what gets methylated and acelytaed
methylated: base (cytosine)
acetylation: lyzine
difference btwn genome and epigenome
genome is set of DNA and it is static. On the other hand, epigenome is chem modification that regulates gene expression without changing DNA sequence it is dynamic
what does epigenome do
ctrl gene expression
whats weird about epigenetics
it can be inherited CALLED TRANSGENERATIONAL EPIGENETIC INHERITANCE
what is the definition of epigenetics
Study of changed in gene expression caused by mechanisms other than changed in the underlying DNA sequence (methyl or acetyl grp)
how does methylation of cytosine affect gene expression
DNMT Methylation: deactivates transcription, silencing gene expression VIA heterochromatin
TET Demethylation: activates transcription VIA euchromatin
How does acetylation of histones affect gene expression
HAT acetylates histones: removes positive charges from lysine, loosen chromatin structure, increases transcription
HDAC deacetylases: restore positive charges itghtening histones grip on DNA. compact chromatin structure. decreases transcription
Definition of Heterochromatin
highly condensed chromatin that is transcriptionally inactive. genes in heterochromatin is silenced cuz no transcription associated with DNA methylation
definition of euchromatin
loosely packed chromatin that is transcriptionally active. genes in this region can be transcribed. associated with demethylation and histone acetylation
What is the epigenome of twins (identical genome)
at birth its the same but over time it changes due to environmental influences and aging
what is epigenetic drift
epigenetic modifications over time: Basically twins with identical genome will have different epigenome due to their lifestyles leading to different behaviours and other traits
What is the glucocorticoid receptor (GR)
It binds with corticosterone, making gene and lowers the transcription rate of the protein that makes cortisol
what is epigenetic influence and what is the effect on the offspring Maternal grooming and methylation
maternal grooming reduces methylation of the promoter of the glucocorticoid receptor gene increasing GR expression
Effects on offspring: High grooming mothers lead to offspring with reduced anxiety and a lower corticosterone response to stress.
what is the cross-Fostering Studies
When the pup r switched with parents, an epigenetic marker shift. Mother pups raise their offspring based on how they were raised
What is Transgenerational Epigenetic Inheritance. and what is the result on monkeys
Early life: Gene expression can be inherited by offspring
Maternal care on monkeys: similar epigenetic modifications observed where maternal care affects the behaviour and stress response of offspring, leading to lasting changed in the epigenome
Human diseases, disorders and behaviours linked to epigenetics
anxiety risk-taking behaviourm stress responses, eating habits, drug addiction, bipolar disorder, suicide, schizophrenia, depression obesity, memory-related issues
DNMT Inhibitors and CRISPR-dCas9 in Epigenetic Therapy
DNMT Inhibitors: prevents methylation and potentially reactivating silenced tumor suppressor genes
CRISPR-dCas9 in genome editing: its CRISPR without the cutting abilities but can target regions of DNA to modify epigenetic mark
what is an epigenetic clock
Measures biological age based on methylation patterns
Chronological vs biological age
Biological aging: cellular aging may differ from chronological age
What is Epigenetic age acceleration
Faster aging of tissues can be detected through this clock, which serves as a biomarker for disease risk
