Characterization of candidate genes governing complex multicellularity in Neurospora crassa
Wong, Jie Yun
Date of Issue2017-05-02
School of Biological Sciences
Temasek Life Sciences Laboratory
Complex multicellularity (CM) occurs exclusively in the Eukarya domain and emerged independently within six distinct eukaryotic clades including ascomycete fungi such as Neurospora crassa. All CM organisms are characterized by three-dimensional (3D) cellular organization, cell differentiation and intercellular communication. It was hypothesized that new aspects of CM could be discovered by searching for genes present in CM fungi but absent in unicellular yeast counterparts. To this end, we performed bioinformatics analysis to identify genes expressed in Pezizomycotina and Neolecta irregularis but absent in budding and fission yeast. In total, we identified 147 genes that fit our criteria and we characterized four of which displayed an observable growth defect in N. crassa knockout strains. Interestingly, the protein product of one of the candidate gene, ROGDI, was found to interact with a subunit of the Vacuolar H+-translocating ATPase (V- ATPase) complex as part of the Regulator of ATPase of Vacuoles and Endosomes (RAVE) complex and could potentially function to maintain vacuolar pH levels. Another candidate protein, Spz1, was shown to interact with proteins known to function in cell polarity through its coiled- coil domain. Altogether, the results from this study provide clues on the extant of genes required for CM.