epigenetics Flashcards
definition
heritable phenotype changes in a chromosome without alteration in DNA sequence
what can lead to changes in the gene expression
modifying DNA structure without modifying DNA coding
what is epigenetic codes
epigenetic features that maintain different phenotypes in different cells
how different phenotypes occur
changes in structure and folding of DNA ( methylation) but not in BASES
epigenome
location of methylation, multitude of chemical compounds
why do we need epigenetic
- DNA is extremely long - to pack
- provides instructions for specific genes
- heritable and adapts to environment ( can decrease or increase activity )
- specific signatures
two types of methylation
modification to DNA and modification to histone
what does DNMT- DNA methyltrasnferase do
catalyses the transfer of CH3 from S-adinomethyonine and adds CH3 to CpG islands
what are carriers of methyl group
B12, B6 and folate
highly wound DNA is
heterochromatin
loosely packed DNA
euchromatin
what is the first step in compacting the DNA
winding DNA around histone proteins ( not in DNA modification)
when DNA modification changes occur
during differentiation
as s response to environment
what are methyl donors in humans
B6, B12, folate , choline, methionine and B2
