Role of two Nomuraea rileyi transmembrane sensors Sho1p and Sln1p in adaptation to stress due to changing culture conditions during microsclerotia development.

Microsclerotia (MS) formation was successfully induced in Nomuraea rileyi in liquid amended medium (AM) culture. To investigate how N. rileyi senses growth stress and regulates MS differentiation, based on transcriptome library, sho1 and sln1 genes were cloned. The transcription levels of sho1 and sln1 were upregulated in response to the changing culture conditions. To determine the functions of sho1 and sln1, gene-silencing mutants (sholi, sln1i and shol&sln1i) were generated using RNA silencing technology. The significant phenotypic changes in the mutants included reduced conidial yields by 22.72, 40.27, and 63.67 % and virulence by 24.53, 25.74, and 59.04 %, respectively. Furthermore, the mutants presented decreased MS yields by approximately 96 % under changing culture conditions. Our results confirmed the crucial role of Sho1p and Sln1p in sensing growth stress due to changing culture conditions and regulating MS differentiation.