# HG changeset patch # User Steve Losh # Date 1695657236 14400 # Node ID 3c6edc9a220d64ba7c7d0481e3a08406c397446b # Parent 8c1652a33df6fd42be960295d317be184086ac95 Update diff -r 8c1652a33df6 -r 3c6edc9a220d README.markdown --- a/README.markdown Sat Sep 23 21:42:21 2023 -0400 +++ b/README.markdown Mon Sep 25 11:53:56 2023 -0400 @@ -1011,4 +1011,33 @@ Came up with some absolutely cursed code to made shaded normal graphs. Surprised that's not already a thing. +## 2023-09-25 +HG545. Need to retype all my notes for this module here when I get some time so +I don't lose them. + +Today started with a description of RNAseq. Something vaguely familiar was +a nice change for this class. Then reviewed STARR-seq which I think I mostly +understand now. + +Talked about the similarity between enhancers and promoters. Polymerase can +sometimes actually sit down at enhancers and produce small RNAs, but +transcription doesn't ever elongate. But this might be an example of how genes +could evolve. + +Then talked about heat shock proteins and heat shock factor as an example of how +rapid transcription can happen. + +* HSE: "Heat Shock Element", an enhancer sequence located upstream of a gene, + e.g. hsp90. +* hsp90: "Heat Shock Protein 90", a protein that's used in cells to help other + proteins fold in the presence of heat that might otherwise prevent it. The 90 + is from its weight in kilodaltons (lol). +* HSF1: "Heat Shock Factor 1", a transcription factor that trimerizes, binds to + HSE, and recruits another thing to activate the transcription of hsp90. + +There's a self-regulation loop here where, when things are cold, hsp90 binds to +HSF1 outside the nucleus and prevents it from enhancing transcription of hsp90 +(i.e. of itself). But when heat is applied, other proteins unfold and hsp90 +starts chaperoning them more, which leaves HSF1 free to enter the nucleus and +enhance transcription of hsp90.