BIOL 203 Lecture Notes - Lecture 17: Trp Operon, Non-Coding Rna, Repressor
Document Summary
Conducting the genetic orchestra: prokaryotes and eukaryotes alter gene expression in response to their changing environment, multicellular eukaryotes. Responsible for differences in cell types (liver, lung, kidney, heart, etc. ) Dna is the same in every cell, but different genes are turned on and others are turned off in order to make different types of cells. Rna molecules are important in gene expression. Sometime enzymes are coded together on the same chromosomes. Repressors are allosteric proteins two shapes depending on if a molecule is bound to it or not one active, one inactive. Can be in an active or inactive form depending on presence of other molecules. !1: makes sure there is a balance in cells, not too much or too little of a substance, corepressor: a molecule that cooperates with repressor protein to switch off the operon. When bound to repressor, puts it in its active form. Usually an end product of the pathways.
