BIOB11H3 Lecture Notes - Lecture 11: Histone Acetyltransferase, Heterochromatin Protein 1, Tata Box
Document Summary
Biob11-l11: gene regulation 3 epigenetics & miscellaneous gene regulatory mechanisms. Information flow through dna to rna to protein. Mechanisms that alter expression but which do not involve changes to. Dna sequence (i. e. no mutations) e. g. modifications of dna & histones (often a functional group [e. g. methyl] is added/ lost) Modification of histones group etc causes the expression of genes by decondensing & condensing chromatin. Interphase: decondensed transcriptionally active state (continuously expressing for growth & survive) Mitosis: condensed, transcriptionally silent state (ready to split and undergo mitosis) Constitutive heterochromatin: always condensed (e. g. repetitive dnas of centromeres) Facultative heterochromatin: condensed depending on cell type, stage of development or other stimulus (e. g. x-chromosome inactivation in females) During embryogenesis, one of the two x chromosomes in females is inactivated. Calico cat one x: black coat // other x: orange coat. The cat has clusters of different area of black & orange coat, giving rise to two different colors of fur on the cat.
