Regulation of gene expression Flashcards
describe gene nomenclature
-all leters in a gene name are italicized
- human gene names are all capitalized
-mouse gene names are only first letter capitalized
what are some gene specific requirements
-intracellular hormone receptor complexes (steroids)
- intracellular second messengers (peptide hormones)
- gene specific transcription factors
- gene regulatory sequences
what is a helix loop helix
common in transcription factors and consists of alpha helices bound by a looping stretch of amino acids
what are DNA binding zinc finger motifs
multiple types, but all have a bound zinc metal ion associated with the protein. some have an alpha helix plus beta sheet structure, others have a more helix-turn-helix sstructural motif
- generally binds over larger stretch of DNA
what are helix turn helix
DNA binding motif with 2 alpha helices form a Y shaped coiled coil structure, results in both protein and DNA bindinf
what do the majority of DNA binding proteins function as
dimers or tandem clusters
what does the leucine zipper do
promotes both DNA binding and dimerization
in prokaryotes where is the start of transcipriton in relation to the location of the control sequences
the repressor and activator binding sites are generally closely juxtaposed to the RNA polymerase binding site
in eukaryotes where is the start of transcription in relation to the location of the control sequences
DNA regulatory sequences can be located at great distances relative to the start site of transcription, be found in the 5’ to 3’ flanking regions and in introns
where is the TATA box located and what does it bind
~25-30 BP 5’ of the start site of transcription and binds TBP subunit of TFIID
what does the INR contain and what does it bind
start site of transcription for many RNA pol II genes and binds TFIID
where is DPE located and what does it bind
located at +30 3’ of the start site and binds TFIID
where is BRE located and what does it bind
located at -35 5’ of the start site and binds TFIIB
what are the steps of activatino of transcription at a specific promotor
gene activator protein binds to chromatin -> chromatin remodeling -> covalent histone modification -> addition activator proteins bound to gene regulatory proteins -> assembly of pre-initiation complex at the promoter -> transcription initiation
what controls the mRNA in the cytosol
microRNA
what is linkage analysis
-the autosomes and X chromosome are amendable to linkage mapping studies because they undergo recombinaiton
- y chromosomes does not undergo recombination
what is the most common used technology for identifying disease causing genes
DNA/RNA sequencing coupled with software and databases to identify mutations in genes
- exome sequencing
what does genome sequencing invole
entire genome sequences
what does exons sequencing involed
only protein coding regions
what does transcriptomic sequencing or RNA sequencing involve
genes that are being sequences
what do epigenomics involve
-dna methylation
-ChIP sequencing
-ribosome profiling
what are some rare bone diseases
-osteoporosis pseudoglioma syndrome
- high bone mass
-scleroteosis / Van buchem disease
what gene is identified in many bone trait diseases
LRP5
what bone diseases are loss of functino mutations
osteoporosis pseudoglioma
what bone diseases are gain of function mutations
high bone mass
describe the Wnt/beta catenin signaling pathway
- Wnt binds to LRP5 and frizzled protein
- release of beta catenin and it goes into nucleus where it binds to TCF
what mutation causes sclerosteeosis and van buchems disease
SOST gene
what is the mechanism of action of sclerostin
binds LRP5 and inhibits Wnt/beta catenin signaling
