BIOC 4403 Lecture Notes - Lecture 3: Last Universal Common Ancestor, Gene Duplication, Noncoding Dna
27 Mar 2017
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Document Summary
Can infer that luca had a dsdna genome. Genes involved in house-keeping functions, core metabolic functions. From pre-existing genes (via duplication or horizontal gene transfer) Examples: the globin gene family, tubulin gene family, hsp90 gene family. Large prevalence of gene duplication in all 3 domains of life. Dna-based duplication relies on repetitive element, unequal crossing over. Rna-based duplication mrna made into cdna that can be randomly inserted into genome, gene must acquire a promoter: retrogenes can deteriorate if they don"t acquire a promotor. Dna-based gene fusion can end up with stretches of dna that code parts of one gene and parts of another exons from nearby genes being spliced together accidentally. Transcription-mediated gene fusion formation of a chimeric retrogene via splicing signal evolving. Orthologs: genes/proteins in different species that evolved from a common ancestral gene by speciation; orthologues typically have the same function in different species.
