A CYC/TB1-type TCP transcription factor controls spikelet meristem identity in barley. (11th September 2020)

• Record Type: Journal Article
• Authors: Shang, Yi; Yuan, Lu; Di, Zhaocan; Jia, Yong; Zhang, Zhenlan; Li, Sujuan; Xing, Liping; Qi, Zengjun; Wang, Xiaoyun; Zhu, Jinghuan; Hua, Wei; Wu, Xiaojian; Zhu, Minqiu; Li, Gang; Li, Chengdao
• Editors: Wellmer, Frank
• Is Part Of: Journal of experimental botany. Volume 71:Number 22(2020)
• Page Start: 7118
• Page End: 7131
• Publication Date: 2020-09-11
• Subjects: Barley -- BRANCHED AND INDETERMINATE SPIKELET 1 (BDI1) -- deletion -- determinacy -- inflorescence architecture -- map-based cloning -- spikelet meristem -- TCP transcription factor -- transcriptome sequencing (RNA-Seq) -- virus-induced gene silencing (VIGS); Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/eraa416
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: Barley possesses a branchless, spike-shaped inflorescence where determinate spikelets attach directly to the main axis, but the developmental mechanism of spikelet identity remains largely unknown. Here we report the functional analysis of the barley gene BRANCHED AND INDETERMINATE SPIKELET 1 ( BDI1 ), which encodes a TCP transcription factor and plays a crucial role in determining barley inflorescence architecture and spikelet development. The bdi1 mutant exhibited indeterminate spikelet meristems that continued to grow and differentiate after producing a floret meristem; some spikelet meristems at the base of the spike formed two fully developed seeds or converted to branched spikelets, producing a branched inflorescence. Map-based cloning analysis showed that this mutant has a deletion of ~600 kb on chromosome 5H containing three putative genes. Expression analysis and virus-induced gene silencing confirmed that the causative gene, BDI1, encodes a CYC/TB1-type TCP transcription factor and is highly conserved in both wild and cultivated barley. Transcriptome and regulatory network analysis demonstrated that BDI1 may integrate regulation of gene transcription cell wall modification and known trehalose-6-phosphate homeostasis to control spikelet development. Together, our findings reveal that BDI1 represents a key regulator of inflorescence architecture and meristem determinacy in cereal crop plants. Abstract : We have identified a grass-specific TCP transcription factor, BRANCHED AND INDETERMINATE SPIKELET 1 (BDI1), from barley, which controls the spikelet identity and inflorescence architecture.