Survival of duplicate genes in the vertebrate genome: A matter of splice or death

Abstract

Why do some duplicate genes survive while others are lost? After duplication, most extra gene copies soon accumulate disabling mutations and degrade, but some are retained. Although there are several models proposed to explain fates of duplicated genes factors associated with duplicate gene retention remain poorly understood. Here, we analyse gene duplicate retention after whole genome duplication events at the base of the vertebrate lineage. We show that ancestral alternative splicing -a process by which a single gene can encode more than one distinct protein- in invertebrate single copy genes increased significantly the number of orthologous present in vertebrate genomes. Similar results were observed for non-singletons in the invertebrate genomes. Furthermore, we find that a higher number of orthologous in vertebrate genomes is associated with significantly lower expansion of alternative splicing consistent with the two processes being to some extent equivalent ways to increase transcript diversity. After that, bias of the reliability of our database was clarified. Finally, we found the complexity of species also provide a positive correlation with duplicates and splicing. These observations are consistent with the view that alternative splicing shapes the survival chances of duplicate genes by facilitating functional split between gene copies.

Date of Award	22 Nov 2018
Original language	English
Awarding Institution	University of Bath
Supervisor	Araxi Urrutia (Supervisor) & Nick Longrich (Supervisor)