Investigating how the DOC proteins mediate intercellular communication discrimination in Neurospora crassa

Germinated asexual spores of Neurospora crassa detect the presence of genetically identical partners, communicate with and grow towards them, and fuse to form a syncytium. We previously found that genetically distinct isolates from the same population fall into exclusive communication groups (CGs) and we used bulk segregant analysis to identify a single locus containing one to three paralogous genes associated with CG. Although the two genes at the CG locus in our lab strain are not essential for self-communication, we demonstrated that they are necessary and sufficient to specify CG (Heller et al. 2016). We named these genes determinant of communication (doc) 1 and 2. doc-1 and doc-2 have no characterized homologs, nor have we identified any protein domains within them. We developed a flow cytometry-based communcation quantification system to assay doc mutants, but the mechanism by which the doc genes control CG remains elusive.