OsMADS17 simultaneously increases grain number and grain weight in rice

Area of Science:

• Plant Biology
• Genetics
• Agricultural Science

Background:

• Increasing rice yield is crucial for global food security.
• A common challenge in rice breeding is the trade-off between grain number and grain weight.

Purpose of the Study:

• To identify genes controlling rice yield by overcoming the grain number-weight trade-off.
• To elucidate the molecular mechanisms regulating rice grain yield.

Main Methods:

• Gene identification and characterization (COG1/OsMADS17).
• Analysis of 5' untranslated region (UTR) deletion effects on translation efficiency.
• Investigating gene regulatory networks involving OsMADS17 and OsAP2-39.

Main Results:

• A 65-bp deletion in the 5' UTR of COG1 (OsMADS17) in cultivated rice enhances grain number and weight simultaneously.
• OsMADS17 regulates multiple genes, including OsAP2-39, impacting grain yield.
• OsMADS17 expression is directly regulated by OsMADS1, forming an OsMADS1-OsMADS17-OsAP2-39 regulatory pathway.

Conclusions:

• The OsMADS1-OsMADS17-OsAP2-39 pathway is a key regulator of rice grain yield.
• Downregulating OsMADS17 or OsAP2-39 can improve rice yield by increasing both grain number and weight.
• This research provides a molecular basis for breeding high-yield rice varieties.