L16 Flashcards
what levels is expression regulated at? (3)
transcriptional
post transcriptional
post translational
transcriptional regulation involves what
transcriptional activation or repression
epigenetic regulation
post transcriptional regulation
RNA processing
RNA localization
selective degradation / translation of RNA
pre translational regulation
selective degradation of proteins
covalent modification
enhancers enable cells to ____________ responses to signals
coordinate
transcription factor outcomes dependent on what
developmental history
signals in the microenvironment
one trascription factor can induce the expression of many genes, because many genes share the same __________
regulatory sequences
regulatory sequences can control _______ that genes are expressed
temporal order
temporal and spatial patterns of gene expression are determined by cascades of __________
transcription factor activity
gradients can be refined by ________
mutual activation + repression
gradients of transcription factors are subsequently refined by mutual activation and repression, and this is beause the genes have binding sites for transcription factors encoded by other _________ genes in their _______
segmentation
enhancers
cell differentiation is regulated by activity of specific combo of _______
transcription factors
transcription factors regulate gene expression by binding to ________
genomic regulatory sequences
__________ can be hardwired into genome
transcription cascades
cells highlight regions of these genomes (transcriptional memory) by what
modifying chromatins
what are the two main components of the epigenetic code?
DNA methylation
histone modification
DNA methylation occurs at s ______, where CH3 is added to the _____ (carbon at 5th psition in the ring). this does / does not interfere with H bonding, and can / cannot interfere with binding of proteins in the major groove
CpG-dunucleotide
cytosine
does not
can
what is the role of DNA methylation?
inverse relationship between cytosine methylation and transcription
repression can be a result of
direct interference with transcription factor
specific binding of transcriptional repressor
altered chromatin structure
methylation occurs at _____ islands around _______ of genes
CPG
promotors
epigenetic and transcriptional programming determines _______
potential
how are epigenetic marks maintained?
maintenance replication genomes
vertebrate cytosine methyl-transferases have preference for hemi-methylated targets
spatially restricted transcription factors such as____ establish _______ patterns of homeotic gene
Hb
spatially restricted
PcG and TrxG proteins maintain the ___________ respectively after the spatially restricted factors are gone
repressed and active states
ontogeny
strcutres controled vocab for describing dif cell types
mrf4 does what
helps to connect cells to myoblasts
Identity of a cell is acquired via ___________ and preserved throughout its______
cell differentiation
lineage
Accessibility of transcription factors to DNA is determined by ___________
epigenetic modifications
__________ involving transcription factors and the ______________ during DNA replication ensures the preservation of _______ during cell proliferation
Feedback mechanisms
copying of the epigenetic marks
cell identity
____________ in the stem cell niche influence cell fate via regulating the expression/function of ___________
Microenvironmental signals
genetic and epigenetic factors.
