MCD BIO 165A Lecture 15: lecture 15 POST-TRANSLATIONAL MODIFICATIONS
10 Jan 2019
School
Course
Professor
Document Summary
Long non-coding dna, junk dna: we share 92% gene with mouse, 98% with chimp, 44% with drosophila. Generation of different mrna transcripts from a single gene. Post-translational modifications of proteins: proteome complexity can be upped x5 compared to # of genes, post-translational modifications (ptm) increases functional diversity of proteome by: Covalent addition of functional groups or proteins. Post-translational modifications (ptm: occur at distinct amino acid side chains or peptide linkages and are mediated by enzymatic activity, estimated that 5% of proteome comprises enzymes that perform more than 200 types of. Transferases add or remove functional groups, proteins, lipids or sugars to or from aa chains chemical specificity: e. g. phosphate can only be added to tyr, thr, ser. Active/inactive ; allows protein function that was previously not possible. Ligases (e. g. addition of ubiquitin: biologically active insulin requires ptms. In most cases protein made in a zymogen state (inactive protein) Zymogen: inactive form of protein; only activated when cleaved.
