The transcription factor OsWRKY36 regulates leaf angle in rice by modulating brassinosteroid signaling

Area of Science:

• Plant Biology
• Molecular Genetics
• Agricultural Science

Background:

• WRKY transcription factors are crucial for plant responses to environmental stimuli.
• While their role in stress resistance is well-studied, their function in regulating plant growth and development remains less understood.

Purpose of the Study:

• To identify and characterize rice WRKY transcription factors involved in regulating plant architecture.
• To elucidate the molecular mechanism by which OsWRKY36 controls rice leaf angle and plant architecture.

Main Methods:

• Identification of OsWRKY36 from a rice mutant library.
• Analysis of OsWRKY36 expression patterns and functional assays in planta.
• Investigation of protein-protein interactions using co-immunoprecipitation and yeast two-hybrid assays.
• Analysis of gene expression using quantitative real-time PCR.

Main Results:

• OsWRKY36 is identified as a key regulator of rice leaf angle and plant architecture.
• OsWRKY36 promotes adaxial parenchyma cell growth and expansion, increasing leaf angle.
• OsPUB24, an E3 ubiquitin ligase, interacts with OsWRKY36 and targets it for degradation, negatively regulating leaf angle.
• OsWRKY36 interacts with DLT, a positive BR signaling regulator, to activate OsBZR4 expression, positively regulating leaf inclination.
• Brassinosteroid (BR) signaling stabilizes OsWRKY36 by inhibiting OsPUB24.

Conclusions:

• OsWRKY36 acts as a crucial link between brassinosteroid signaling and the regulation of rice leaf inclination and plant architecture.
• The study reveals a novel regulatory module involving OsPUB24, OsWRKY36, DLT, and OsBZR4 in BR-mediated growth.
• Findings provide insights into optimizing crop architecture through manipulation of BR signaling pathways.