An atypical bHLH protein encoded by <i>POSITIVE REGULATOR OF GRAIN LENGTH 2</i> is involved in controlling grain length and weight of rice through interaction with a typical bHLH protein APG

• DOI: 10.1270/jsbbs.62.133
• Publication Date: 2012-06-19T22:42:48Z
• Authors: Dany Heang; Hidenori Sassa
• Keywords: 2. Zero hunger; 0303 health sciences; 03 medical and health sciences; Research Papers

Grain size is an important yield component in rice, however, genes controlling the trait remain poorly understood. Previously, we have shown that antagonistic pair of basic helix-loop-helix (bHLH) proteins, POSITIVE REGULATOR OF GRAIN LENGTH 1 (PGL1) and ANTAGONIST PGL1 (APG), involved rice grain length. Here, report involvement another atypical bHLH protein gene, 2 (PGL2), regulation Over-expression PGL2 lemma/palea increased length weight correlation with level transgene expression. Observation inner epidermal cells lemma PGL2-overexpressing lines revealed long caused by increase cell interacts a typical APG, negative regulator weight, vitro vivo. It was reported overexpression BU1 (BRASSINOSTEROID UPREGULATED 1), closest homolog PGL2, However, detected no interaction between APG. These findings suggest redundantly suppress function APG forming heterodimers to positively regulate length, while pathway through which BU1, controls independent