Volume 19 Part 1 Article 66
Title: Regulation of fruiting body development in Coprinopsis cinerea
Author: Ursula Kües, Shanta Subba, Yidong Yu, Mandira Sen, Weeradej Khonsuntia, Wassana Singhaduang, Karin Lange and Kiran Lakkireddy
The edible mushroom Coprinopsis cinerea is an excellent model to study the genetics of fruiting body development in the Agaricomycetes. Fruiting follows a conserved scheme defined by day and night phases, with well predictable distinct stages over the time. Fruiting starts with primary hyphal knot formation in the dark, followed by aggregation into compact round secondary hyphal knots in which stipe and cap tissues differentiate. Primordia development (stages P1 to P5) takes five days to culminate on day 6 of development in karyogamy and meiosis within the basidia and subsequent basidiospore production which parallels fruiting body maturation (stipe elongation and cap expansion) during the last day of development. This scheme of development is followed up by normal dikaryons as well as by a self-compatible homokaryon which has mutations in both mating type loci. The matA genes control fruiting body initiation at the stages of primary and secondary hyphal knot formation and the decision to enter the alternate pathway of sclerotia formation. matA induced steps in fruiting end at the P4 state. Activation of the matB genes is required for karyogamy and fruiting body maturation. Further, matB activation enhances the frequency of matA-induced fruiting. matB functions as a mediator between light and nutritional signals and matA control of development. We have a large collection of about 1500 mutants in fruiting body development. Mutations do not evenly distribute over the developmental pathway of fruiting body development. High numbers of mutants are available from the developmental stages of primary and secondary hyphal knot formation up to stage P1. Comparably few mutations resulted in defects in the developmental progress from P1 to P4 but high numbers of mutants were found also in the later developmental processes occurring normally on day 6 for fruiting body maturation and sporulation. In our studies, we focus on genes that act at the first stages in fruiting. Mutants with defects in primary and secondary hyphal knot formation helped before by complementation to clone genes cfs1 and a gene of the NWD2 family. We study the functions of these and further genes with predicted functions in regulation and light control of early fruiting body development.