F-box proteins are a core component of Skp1-Cul1-F-box (SCF) ubiquitin/ligase complexes and are involved in a lot of cellular processes in yeasts. However, the current knowledge of the molecular evolution of the F-box gene family in yeasts remains unclear. In this study, 136 F-box genes were identified in 10 yeast species of the Saccharomycetaceae. In addition to the F-box domain, the other six domains were identified in these F-box proteins. The evolutionary history of F-box gene numbers in 10 Saccharomycetaceae yeasts was reconstructed. Whole-genome duplication, interspersed repeats, and gene loss events were inferred. These events contributed to F-box gene number variation in the 10 yeast species. Eighty-seven and 33 positively selected sites were detected in program Selecton and Datamonkey web-server, respectively. Three of them were considered the significant positively selected sites, and 23 of them had changed radically in amino acid properties by using TreeSAAP. We investigated F-box gene number variation and underlying mechanisms, and selection patterns, all of which were beneficial to deeply understand genome evolution and figure out the function of the F-box proteins.
Keywords: F-box gene; Saccharomycetaceae; evolution; gene family.