RT Journal Article
SR Electronic
T1 Tissue-specificity of gene expression diverges slowly between orthologs, and rapidly between paralogs
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 065086
DO 10.1101/065086
A1 Nadezda Kryuchkova-Mostacci
A1 Marc Robinson-Rechavi
YR 2016
UL http://biorxiv.org/content/early/2016/07/21/065086.abstract
AB The ortholog conjecture implies that functional similarity between orthologous genes is higher than between paralogs. It has been supported using levels of expression and Gene Ontology term analysis previously, although the evidence was rather weak and there were also conflicting reports. In this study on 12 species we provide strong evidence of high conservation in tissue-specificity between orthologs, in contrast to low conservation between within-species paralogs. This allows us to shed a new light on the evolution of gene expression patterns. While there have been several studies of the correlation of expression between species, little is known about the evolution of tissue-specificity itself. Ortholog tissue-specificity is strongly conserved between all tetrapod species, with the lowest Pearson correlation between mouse and frog at r = 0.66. Tissue-specificity correlation decreases strongly with divergence time. Paralogs in human show much lower conservation, even for recent Primate-specific paralogs. Small-scale tissue-specific paralogs are mostly specific for the same tissue, while ancient whole genome duplication paralogs are often specific for different tissues. The same patterns are observed using human or mouse as focal species and are robust to choices of datasets and of thresholds.