Patterns of putative gene loss suggest rampant developmental system drift in nematodes

摘要: Gene loss often contributes to the evolution of adaptive traits. Conversely, null mutations frequently reveal no obvious phenotypic consequences. How pervasive is gene loss, what kinds genes are dispensable, and consequences loss? The nematode Caenorhabditis elegans has long been at forefront genetic research, yet only recently have genomic resources become available situate this species in its comparative phylogenetic evolutionary context. Here, patterns within evaluated using 28 genomes (most them sequenced past few years). Orthologous detected every except one were defined as being lost that species. Putative functional roles determined information from C. WormBase ontology terms well existing transcriptomic datasets. All multiple a species-specific manner, with genus-wide average several dozen per Counterintuitively, nearly all perform essential functions (an third species). Retained differences transcriptional abundance across developmental stages when considering Caenorhabitis genomes. However, subgeneric Elegans group, tend lower expression than retained genes. Taken together, these results suggest genetics processes evolving rapidly despite highly conserved adult morphology cell lineage phenomenon known system drift. These highlight importance approach interpreting findings model systems genetics.