SHATTERING ABORTION1, A new player in seed shattering of rice

Seed shattering is an adaptive trait for seed dispersal in wild plants. However, the seed shattering habit causes yield loss for domesticated crop plants during harvest. Our ancestors began domesticating crop plants by selecting grains that had reduced seed-shattering characteristics.

Professor HAN Bin at the Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and co-workers identified an AP2 transcription factor SHATTERING ABORTION1 (SHAT1) as being required for seed shatter in rice (Oryza sativa) through affecting seed abscission zone development.

The authors isolated shat1 mutant in the genetic background containing known shattering genes SH4 and qSH1. They have made use of a clever approach to discover a new factor involved in specification of the abscission zone of rice seeds, in the process elucidating the roles of previously known factors. SHAT1 was shown to be highly expressed in the abscission zone. Further study indicated SHAT1 serves to maintain SH4 expression in the abscission zone. Furthermore, qSH1 appears to promote shattering by maintaining SHAT1 and SH4 expression in the abscission zone.

This work was published in The Plant Cell online (10.1105/tpc.111.094383). Meanwhile, the editor published a brief comment and highly evaluated this work. (Bin Han)