SHAT2 Transcription Factor Influences Rice Seed Shattering and Grain Traits

In natural ecosystems, the timely abscission of seeds in wild plants is a crucial adaptive trait that contributes to reproductive success, population renewal, and colony expansion. While rice varieties with strong resistance to seed shattering may have reduced yield losses during harvest, this characteristic is increasingly aligned with the requirements of modern agricultural practices. Therefore, enhancing the genetic resistance to seed shattering in rice is essential for ensuring stable yields and improving adaptability to mechanized farming.

Paving the way towards that goal, a team of researchers from China has successfully identified SHAT2, an AP2/ERF transcription factor that acts as a positive regulator of both seed shattering and seed quality in rice.

The team published their findings in the Journal of Integrative Agriculture.

We are currently screening the transgenic library (Wuyunjing 7) generated through CRISPR-Cas9 technology for materials that may be associated with rice seed shattering and possess potential research value. Several shat2 allelic mutants were identified by CRISPR-Cas9 technology."

Qian Qian, corresponding author, academician at the Chinese Academy of Sciences and professor at China National Rice Research Institute

Notably, the shat2 allelic mutants exhibited impacts on seed shattering and grain quality, suggesting the substantial potential of SHAT2 for application in breeding rice varieties with desirable shattering characteristics and superior grain quality.

"We investigated the expression pattern of SHAT2 using real-time quantitative PCR and found that SHAT2 was expressed in various organs," adds Qian.

The expression levels of most genes related to seed shattering and grain quality were down-regulated in the shat2 mutants, indicating that SHAT2 might control seed shattering and quality by regulating the expression levels of these related genes. 

The authors recommend that future endeavors should involve a comprehensive analysis of the regulatory effects of SHAT2 on shattering and quality. Building on this foundation, the strategy for future studies will involve genetically engineering suitable shattering and high-quality rice germplasms/varieties centered around SHAT2

"By doing so, we can broaden the spectrum of rice genetic resources with suitable seed shattering and good grain quality traits, which are crucial for ensuring stable yields and compatibility with mechanized production," says Qian.