Genomics 124 Final Questions And Answers

Describe the phylogeny of GRs? - ️️Bees. Only about 350 to 400 ORs. Ants have the record for ORs. Unlike honey bees, actually expansion in GRs (also true of Nasonia). Bees lost this shit, down to like 12. Basic pathway of RNAi - ️️1. double stranded RNA is recognized by an enzyme, dicer and cleaved into short piece abotu 21 bp long 2. These 21 bp long sections are recognized by a complex of proteins called RISC (RNA induced silencing complex) which uses them to recognize perfectly matching mRNAs and cleave them into 21 base pieces, which can then feed back into the process. Additional aspect are that there is an RNA importer protein in nematodes and vertebrates called SID that facilitates update of double stranded RNA. This process can spread and persist in animals across one generation in nematodes by a RNA mediated RNA polymerase. This is missing in insects. Compare Bombyx mori genome to fly genomes? What is different about gene size? Why? What about protein number? Gene sets? Chromosome number? - ️️5x bigger than Drosophila and 3X bigger than Aedes Transposons occur in introns, so you have very long introns. 1793 unique proteins 28 chromosomes in B. mori, ancestral leps = 31. Describe chemoreceptor evolution? What are some general trends? What about Glossina morsitans (the tsetse fly)? Dasphnia, Strigamia (centipede), and Ixodes? - ️️OR proteins: Drosophila (60), Glossina morsitans - Tsetse fly (42), B. mori (60), Tribolium (265), A. mellifera (170), Nasonia vitripennis (225), Pogomyrmex barbatus (344), Pediculus humanus (10).