OsMS188 Is a Key Regulator of Tapetum Development and Sporopollenin Synthesis in Rice

• Published in: Rice (New York, N.Y.) Vol. 14; no. 1; p. 4
• Main Authors: Han, Yu, Zhou, Si-Da, Fan, Jiong-Jiong, Zhou, Lei, Shi, Qiang-Sheng, Zhang, Yan-Fei, Liu, Xing-Lu, Chen, Xing, Zhu, Jun, Yang, Zhong-Nan
• Format: Journal Article
• Language: English
• Published: New York Springer US 06.01.2021; Springer Nature B.V; SpringerOpen
• Subjects: Agriculture; Assaying; Biomedical and Life Sciences; CRISPR; Degeneration; Electrophoretic mobility; Essential nutrients; Fertility; Gene expression; Genes; Life Sciences; Mutation; Nutrients; Original; Original Article; Phenotypes; Plant Breeding/Biotechnology; Plant cuticle; Plant Ecology; Plant Genetics and Genomics; Plant Sciences; Pollen; Pollen sexine; Rice; Sporopollenin; Synthesis; Tapetum; Transcription factor; Transcription factors; Tapetum; Transcription factor; Sporopollenin; Rice; Pollen sexine
• ISSN: 1939-8425; 1939-8433; 1934-8037
• DOI: 10.1186/s12284-020-00451-y

Background During anther development, the tapetum provides essential nutrients and materials for pollen development. In rice, multiple transcription factors and enzymes essential for tapetum development and pollen wall formation have been cloned from male-sterile lines. Results In this study, we obtained several lines in which the MYB transcription factor OsMS188 was knocked out through the CRISPR-Cas9 approach. The osms188 lines exhibited a male-sterile phenotype with aberrant development and degeneration of tapetal cells, absence of the sexine layer and defective anther cuticles. CYP703A3 , CYP704B2 , OsPKS1 , OsPKS2 , DPW and ABCG15 are sporopollenin synthesis and transport-related genes in rice. Plants with mutations in these genes are male sterile, with a defective sexine layer and anther cuticle. Further biochemical assays demonstrated that OsMS188 binds directly to the promoters of these genes to regulate their expression. UDT1 , OsTDF1 , TDR , bHLH142 and EAT1 are upstream regulators of rice tapetum development. Electrophoretic mobility shift assays (EMSAs) and activation assays revealed that TDR directly regulates OsMS188 expression. Additionally, protein interaction assays indicated that TDR interacts with OsMS188 to regulate downstream gene expression. Conclusion Overall, OsMS188 is a key regulator of tapetum development and pollen wall formation. The gene regulatory network established in this work may facilitate future investigations of fertility regulation in rice and in other crop species.