A natural allele of OsMS1 responds to temperature changes and confers thermosensitive genic male sterility

Changes in ambient temperature influence crop fertility and production. Understanding of how crops sense and respond to temperature is thus crucial for sustainable agriculture. The thermosensitive genic male-sterile (TGMS) lines are widely used for hybrid rice breeding and also provide a good system to investigate the mechanisms underlying temperature sensing and responses in crops. Here, we show that OsMS1 is a histone binding protein, and its natural allele OsMS1(wenmin1) confers thermosensitive male sterility in rice. OsMS1 is primarily localized in nuclei, while OsMS1(wenmin1) is localized in nuclei and cytoplasm. Temperature regulates the abundances of OsMS1 and OsMS1(wenmin1) proteins. The high temperature causes more reduction of OsMS1(wenmin1) than OsMS1 in nuclei. OsMS1 associates with the transcription factor TDR to regulate expression of downstream genes in a temperature-dependent manner. Thus, our findings uncover a thermosensitive mechanism that could be useful for hybrid crop breeding. Thermosensitive genic male-sterile (TGMS) lines are widely used for two-line hybrid rice breeding, but the mechanism of TGMS has not been fully elucidated. Here, the authors show that natural allele of the OsMS1 gene, encoding a histone binding PHD finger protein, responds to temperature change and confers TGMS in rice.