Speciation generates discrete populations, which in turn play an important role for maintaining novel adaptations during evolution. Hybrids between different species are usually inviable or sterile. One of the possible mechanisms causing postzygotic reproductive isolation is incompatibility between genes (speciation genes) from different species. These speciation genes are hypothesized to be some interacting components that cannot function properly when mixed with alleles from different species. Evolution of speciation genes is generally thought to be driven by adaptive evolution. Identifying these genes will provide more information about how speciation occurs.
Our lab uses a few closely related yeast species (the Saccharomyces sensu stricto complex) to identify genetic incompatibility leading to hybrid breakdown. By dissecting the molecular mechanisms of genetic incompatibility, we aim to know the common principles underlying yeast speciation and the driving forces behind the evolution of speciation genes.
Genetic buffering is the mechanism that suppresses phenotypic variation under normal conditions and releases this variation when its function is compromised. Buffering systems are crucial in protecting developmental processes from environmental and genetic perturbations. In addition, buffering systems may play an important role in setting the tempo of evolution since they can moderate these perturbations or help a population accumulate genetic variations essential for selection.
Although the concept of genetic buffering is well established, the mechanisms underlying genetic buffering are largely unclear. In our lab, a systematic approach combining experimental evolution and genomic analysis is used to understand the molecular basis of genetic buffering.