BIOL 1107 Chapter Notes - Chapter 19: Chromatin Remodeling, Histone Code, Post-Translational Modification
Document Summary
Changes in gene expression allow eukaryotic cells to respond to changes in the environment and cause distinct cell types to develop. Eukaryotic dna is packages with proteins into structures that must be opened before transcription can occur. In eukaryotes, transcription is triggered by regulatory proteins that bind to the promoter and to sequences close to and far from the promoter. Once transcription is complete, gene expression is controlled by: alternative splicing, which allows a single gene to code for several different products, molecules that regulate the life span of mrnas, activation or inactivation of protein products. Cancer can develop when mutations disable genes that regulate cell-cycle control genes. The regulation of gene expression is more complex in eukaryotes than in prokaryotes. Differential gene expression: responsible for creating different cell types, arranging them into tissues, and coordinating their activity to form the multicellular society that we call an individual. Swollen spheres in eukaryotes-histones conglomerates-always seen in patterns of four.
