01:119:115 Lecture Notes - Lecture 16: Methyl Group, Histone Methylation, Zygote

• School: Rutgers University
• Department: Biological Science
• Course: 01:119:115
• Professor: Professor Cardinale

Document Summary

A. background and introduction: every cell contains every gene, but different cells are different, not expressing the same genes. B. all individual cells in an organism have the same genes: why different form and function, answer: gene expression regulated. C. gene expression regulated: specific subset of genes active and expressed in each cell, muscles: contraction, neurons: signal transduction, white blood cells: immune. D. constitutive genes: housekeeping genes- always on, encode proteins that are always needed, metabolic genes, example: citric acid cycle. D. what is transcribed: 1 long mrna with all 3 genes, each gene has own start and stop codons, translated as 3 polypeptides, no nucleus in prokaryotes, so, mrna synthesized and translated simultaneously. Negative control: example: lac repressor, repressors turns off operon -> no transcription, only expressed when repressor does not bind, dna sequence change -> prevent repressor binding -> gene always on, 2. ) Positive control: regulation by an activator that binds dna to stimulate transcription.