Biology 1002B Lecture Notes - Lecture 18: Hox Gene, Peptide, Blastula
21 Apr 2017
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Epigenetic = regulation that persists throughout generations or cell lines. Gene expression is inherited from parent cells; not determined by each daughter cell. 2 epigenetic mechanisms = feedback loops and chromatin packaging: feedback loops: product of a gene associates with its promoter; stimulates more of its own transcription. Important for differentiation/dedifferentiation of tissue types: chromatin packaging: densely packed histone-dna regions are called heterochromatin; most genes in these regions are silenced. Histones can be modified by acetylation, methylation, or phosphorylation. Different types of mutations in protein coding genes. Could have a snp that results in no change in the amino acid sequence. You can have much more variation in dna than what shows up in protein sequence; this is due to the redundancy in the genetic code. Could change dna that results in change in a single amino acid. Effect: improper folding of protein or could have no effect at all.
