PSL350H1 Lecture 4: Epigenetics.pdf
Document Summary
Historically, heritable changes in gene expression that do not involve changes to the dna sequence. Now, events that alter gene expression that are not transcriptional regulation: dna alteration, e. g. methylation, histone modifications. Writers: add or modify the target molecule, puts methylation group on/off. Erasers: remove specific modification, takes things off. Readers: bind and identify modifications. Dna: target is cytosine, methylation, hydroxylation if it can be methylated, it can be hydroxylated. Add oh group on methyl group. Mrna (maybe: modified by micrornas binds mrna and inhibits its translation, micrornas are genes that are expressed. Dozens of target sites: mostly lysine (k) Can be a signal in the nucleus. Modifies histone = modifies expression. Tf fox a2 binding dna. Tfs binds to dna and recognizes a dna sequence. Sequences are specific selected for and against a location that drives or repress genes. These can scan a genome, find the coordinate, bind to it, and cause an activity.
