Florigen repression complexes involving rice CENTRORADIALIS2 regulate grain size

Area of Science:

• Plant genetics
• Molecular biology
• Agricultural science

Background:

• Grain size is a key determinant of rice yield.
• Genetic mechanisms controlling rice grain size are not fully understood.
• Florigen repression complexes (FRCs) role in grain size regulation is largely unknown.

Purpose of the Study:

• To elucidate the genetic and molecular mechanisms of FRCs in controlling rice grain size.
• To identify key genes and their interactions regulating grain size in rice.
• To explore strategies for enhancing rice seed size and weight.

Main Methods:

• Gene overexpression and knockout in rice (Oryza sativa L.).
• Yeast two-hybrid and bimolecular fluorescence complementation assays for protein interactions.
• Analysis of cell expansion and division in spikelet hull and seed filling.

Main Results:

• OsCEN2, a PEBP family protein, negatively regulates rice grain size.
• OsCEN2 overexpression reduces grain size; OsCEN2 knockout increases grain size.
• OsCEN2 interacts with GF14f, which interacts with OsFD2, forming a regulatory module controlling cell expansion and seed filling.

Conclusions:

• The OsCEN2-GF14f-OsFD2 module provides novel insights into FRC function in rice.
• Understanding this regulatory pathway offers a strategy for improving rice seed size and yield.
• This study deepens the knowledge of molecular mechanisms governing plant architecture and crop productivity.