Identification and Cloning of a Putative Male Fertility Gene Encoding an Oxidosqualene Cyclase in Qingke

Anther development is crucial for controlling crop fertility. To elucidate the underlying mechanisms of reproductive development of highland barley (called Qingke in Chinese), two main Qingke cultivars, Zangqing 2000 and Ximala 22, were utilized. Transcriptome analysis showed that lipid, sugar and phenylpropane metabolisms might be the major pathways associated with Qingke male fertility by analyzing the possible common DEGs before anther maturation in both varieties. Additionally, 26 genes related to crop genic male sterility were screened to identify homologous genes for Qingke male sterile lines. Among them, HORVU.MOREX.r3.7HG0634780 (HvtOSC12), an oxidosqualene cyclase, was highlighted as a candidate gene for affecting Qingke male fertility, as it is highly and especially expressed before Qingke anther maturation. Furthermore, HvtOSC12 (including promoter sequence) was cloned by homology-based cloning. The further bioinformatic analysis deduced that MYBs might be one of the transcription factors affecting expression of HvtOSC12 by responding to environmental changes. These results might lay a foundation for the potential applications for the creation of environment-sensitive genic male sterility in Qingke.