Differential selection on gene translation efficiency between the filamentous fungus Ashbya gossypii and yeasts
- Equal contributors
1 Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
2 CAS-Max Planck Junior Research Group, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences (CAS), Kunming, Yunnan 650223, PR China
3 Graduate School of Chinese Academy Sciences, Beijing 100039, PR China
4 State Key Laboratory of Cellular and Molecular Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, Yunnan Province, PR China
BMC Evolutionary Biology 2008, 8:343 doi:10.1186/1471-2148-8-343Published: 29 December 2008
The filamentous fungus Ashbya gossypii grows into a multicellular mycelium that is distinct from the unicellular morphology of its closely related yeast species. It has been proposed that genes important for cell cycle regulation play central roles for such phenotypic differences. Because A. gossypii shares an almost identical set of cell cycle genes with the typical yeast Saccharomyces cerevisiae, the differences might occur at the level of orthologous gene regulation. Codon usage patterns were compared to identify orthologous genes with different gene regulation between A. gossypii and nine closely related yeast species.
Here we identified 3,151 orthologous genes between A. gossypii and nine yeast species. Two groups of genes with significant differences in codon usage (gene translation efficiency) were identified between A. gossypii and yeasts. 333 genes (Group I) and 552 genes (Group II) have significantly higher translation efficiency in A. gossypii and yeasts, respectively. Functional enrichment and pathway analysis show that Group I genes are significantly enriched with cell cycle functions whereas Group II genes are biased toward metabolic functions.
Because translation efficiency of a gene is closely related to its functional importance, the observed functional distributions of orthologous genes with different translation efficiency might account for phenotypic differentiation between A. gossypii and yeast species. The results shed light on the mechanisms for pseudohyphal growth in pathogenic yeast species.