AUTHOR=Tao Nan , Cheng Bopu , Chai Hongmei , Cui Xianghua , Ma Yuanhao , Yan Jinping , Zhao Yongchang , Chen Weimin 

TITLE=A Putative Guanosine Triphosphate Cyclohydrolase I Named CaGCH1 Is Involved in Hyphal Branching and Fruiting Development in Cyclocybe aegerita

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.870658

DOI=10.3389/fmicb.2022.870658

ISSN=1664-302X

ABSTRACT=<p>Guanosine triphosphate (GTP) cyclohydrolase I (GCH1) is the limiting enzyme of the tetrahydrobiopterin (BH4) synthesis pathway. The disruption of <italic>gch1</italic> gene may cause conditional lethality due to folic acid auxotrophy in microorganisms, although the function of <italic>gch1</italic> in basidiomycetes has not been deciphered so far. In the present study, <italic>gch1</italic> expression in <italic>Cyclocybe aegerita</italic> (<italic>cagch1</italic>) was downregulated using the RNAi method, which resulted in growth retardation in both solid and liquid medium, with the hyphal tips exhibiting increased branching compared to that in the wild strain. The development of fruiting bodies in the mutant strains was significantly blocked, and there were short and bottle-shaped stipes. The transcriptional profile revealed that the genes of the MAPK pathway may be involved in the regulation of these effects caused by <italic>cagch1</italic> knockdown, which provided an opportunity to study the role of <italic>gch1</italic> in the development process of basidiomycetes.</p>