OsmiR167a‐targeted auxin response factors modulate tiller angle via fine‐tuning auxin distribution in rice

Abstract

Summary Rice tiller angle determines plant growth density and further contributes grain production. Although a few genes have been characterized to regulate tiller angle in rice, the molecular mechanism underlying the control of tiller angle via microRNA is poorly understood. Here, we report that rice tiller angle is controlled by OsmiR167a‐targeted auxin response factors OsARF12, OsARF17 and OsARF25. In the overexpression of OsMIR167a plants, the expression of OsARF12, OsARF17 and OsARF25 was severely repressed and displayed larger tiller angle as well as the osarf12/osarf17 and osarf12/ osarf25 plants. In addition, those plants showed compromised abnormal auxin distribution and less sensitive to gravity. We also demonstrate that OsARF12, OsARF17 and OsARF25 function redundantly and might be involved in HSFA2D and LAZY1‐dependent asymmetric auxin distribution pathway to control rice tiller angle. Our results reveal that OsmiR167a represses its targets, OsARF12, OsARF17 and OsARF25, to control rice tiller angle by fine‐tuning auxin asymmetric distribution in shoots.

Key wheat GRF genes constraining wheat tillering of mutant dmc

“…IAA regulates plant morphological formation, such as plant tropism growth, root development and tiller formation ( Li et al, 2000 ; Ren, Dai & Liu, 2012 ). OsmiR167a represses its targets OsARF12 (auxin response factor, ARF), OsARF17 and OsARF25 , to control rice tiller angle by fine-tuning auxin asymmetric distribution in shoots ( Li et al, 2020 ). GA participates in regulation of many physiological processes in wheat including the spike development, stem elongation, plant height and stress responses ( Zhang et al, 2007 ; Pavlista, Santra & Baltensperger, 2013 ).…”

Population Structure of Nation-Wide Rice in Thailand

“…The Os05g0203800 (OSMADS58) is identified as one of rice C-class MADS box genes which play a crucial role for flower development [13], [14], [15], [16], [17]. The Os06g0677800 (OsARF17) encodes a rice auxin response factor (ARF) transcriptional transcription factor involving in plant defense mechanism different types of plant viruses [18], leaf inclination regulation [19] and tiller angle modulation [20]. The Os09g0433650 is one of genes located in a candidate region on chromosome 9 associated with rice grain shape which was identified in the bulked segregation analysis [21].…”

OsARF11 Promotes Growth, Meristem, Seed, and Vein Formation during Rice Plant Development

“…Loss of OsARF19 function results in enlarged vegetative organs and abnormal flowers [ 45 ], while overexpression indicated a role in tillering angle via regulation of OsGH3-5 and BRI1 [ 46 ]. Furthermore, repression of OsARF12 , 16 , 17, and 25 results in increased leaf inclination [ 47 , 48 ]. As in A. thaliana , microRNAs modulate levels of rice ARF transcripts [ 47 , 49 , 50 ].…”