Term
| why does UV5 mutant of lac operon increase transcription? |
|
Definition
| promoter region betterat binding RNA Polymerase |
|
|
Term
|
Definition
| Code for conversion of galactose to Glu-6-P; set of monocistronic genes which are involved in galactose breakdown pathway; all except GAL5 are closely regulated; expressed when galactose is present and glucose is not |
|
|
Term
|
Definition
| transcription factoer; can regulate expression of nearly all GAL genes; constitutive |
|
|
Term
|
Definition
| prevents GAL4 activation by binding GAL4's transcription activation domain; constitutive |
|
|
Term
|
Definition
| galatose alters conformation which allows it to bind to GAL80 & prevent GAL80 from binding to GAL4 |
|
|
Term
|
Definition
| DNA-binding domain of GAL4; binds to sequence specific DNA elements |
|
|
Term
|
Definition
| transcription activation domain; recruits additional proteins, including co-activators |
|
|
Term
| Upstream activating sequences |
|
Definition
| (UAS); cic-acting binding sites where GAL4 can regulate transcription of the other GAL genes |
|
|
Term
| what is structure of N-terminal DNA binding region of GAL 4? |
|
Definition
|
|
Term
| Why doesn't GAL4 activate GAL genes in presence of glucose and galactose? |
|
Definition
| CRP (catabolite repressor protein) binds GAL4 |
|
|
Term
|
Definition
| DNA sequences that bind activating transcription factors; distance independent |
|
|
Term
|
Definition
| DNA sequences that bind repressing transcription factors; distance independent |
|
|
Term
| Basic steroid hormone regulation |
|
Definition
| glucocorticoid hormone receptor is confomationally changed upon hormone binding, which uncovers zinc finger which binds to DNA sequence called GRE (glucocorticoid response element) which acts like UAS. |
|
|
Term
|
Definition
| modification of base(s) in mRNA molcule to produce more than one protein from the same gene. apoB is an example. |
|
|
Term
|
Definition
| blood lipoprotein gene which produces a different protein in the liver than in the small intestine; difference results from one base modification which leads to stop codon |
|
|
Term
| mRNA stability regulation |
|
Definition
| altered mRNA half-life leads to differences in translation; mRAN w/short half lives often have AU-rich 3' untranslated regions (UTR) |
|
|
Term
| Iron metabolism regulation |
|
Definition
| transferring receptor (TfR) has cis-acting iron response elements (IREs) in its 3' end. These IREs can be bourn by trans-acting iron regulatory proteins (IRPs), which bind when iron is low & prevents degradation of mRNA. |
|
|
Term
|
Definition
| RNA interference; gene silencing thru decreased expression of target mRNA (by repression of translation or by increase degradation); mediated by microRNAs (miRNAs) |
|
|
Term
| gene regulation by translation regulation |
|
Definition
| phosphorylation of eIF2-alpha inhibits function & therefore inhibits translation's 1st step. Kinases regulate eIF2-alpha phosphorylation |
|
|
Term
| Heme controlled inhibitor |
|
Definition
| low heme leads to active protein kinase-->phosphorylation of eIF2-alpha-->decrease in translation. High heme means inactive kinase and increased translation. |
|
|
Term
|
Definition
| increases levels of transcription |
|
|
Term
| regulation by condensation of DNA |
|
Definition
| euchromatin can be inactivated by condensing into heterochromatin |
|
|
Term
| How is one X chromosome inactivated? |
|
Definition
| XIST (x-inactivation-specific transcript) increases methylation of DNA sequences and decreases acetylation of histone proteins, which leads to condensation into heterochromatin |
|
|
Term
|
Definition
| decreases positive charge of histone, which decreases its binding power to negative DNA and relaxes nucleosome; via HATs |
|
|
Term
|
Definition
| highly methylated DNA are less transcriptionally active; C in CG rich areas methylated by methyltransferases; typically in promoter region |
|
|
Term
|
Definition
| number of copies of genes increased, which leads to dysregulation of gene. Happens in cancer & in response to chemo drugs (methotrexate). |
|
|
Term
|
Definition
| increased gene complexity; |
|
|
Term
|
Definition
| drug resistence; disregulation of gene expression |
|
|
Term
|
Definition
| immunoglobins premanently rearrange DNA to bring variable & constant regions closer. This allows for generation of billions of different immunoglobins (which need to recognize various antigens). This sometimes results in loss of DNA and variations in RNA splicing. |
|
|
Term
|
Definition
| mobile pieces of DNA that randomly move from one site to another on same/different chromosome |
|
|
Term
|
Definition
| cut and paste; transposon excised & relocated (generally close to original site) (none active in mammals) |
|
|
Term
| replicative transposition |
|
Definition
| copy & paste; generally w/retrotransposon |
|
|
Term
|
Definition
| transposon converted to RNA, reverse transcribed to DNA & then inserted. |
|
|
Term
| What is LTR & its function? |
|
Definition
| some retrotransposons have long terminal repeats (LTRs), which are very similar in structure to retroviruses. |
|
|
Term
|
Definition
| LINES (found in all mammals), SINES (primates) [long/short interspersed nucleotide elements]. 20% of human genome, but most inactive. |
|
|
Term
| GO OVER REARRANGEMENT OF DNA!! |
|
Definition
| You might need help for this. |
|
|
