Skip to main content
ARS Home » Pacific West Area » Pullman, Washington » WHGQ » Research » Publications at this Location » Publication #396165
Research Project: Genetic Improvement of Wheat and Barley for Environmental Resilience, Disease Resistance, and End-use Quality

Location: Wheat Health, Genetics, and Quality Research

Title: A MYB transcription factor underlying plant height in sorghum qHT7.1 and maize Brachytic 1 loci

Author
item MU, QI - Iowa State University
item WEI, JIALU - Iowa State University
item LONGEST, HALLIE - Iowa State University
item LIU, HUA - University Of Missouri
item CHAR, SI NIAN - University Of Missouri
item HINRICHSEN, JACOB - Iowa State University
item TIBBS CORTES, LAURA - Iowa State University
item SCHOENBAUM, GREGORY - Iowa State University
item YANG, BING - University Of Missouri
item Li, Xianran
item YU, JIANMING - Iowa State University

Submitted to: Plant Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/4/2024
Publication Date: 12/20/2024
Citation: Mu, Q., Wei, J., Longest, H., Char, S., Tibbs Cortes, L., Yang, B., Li, X., Yu, J. 2024. A MYB transcription factor underlying plant height in sorghum qHT7.1 and maize Brachytic 1 loci. Plant Journal. 120:2172-2192. https://doi.org/10.1111/tpj.17111.
DOI: https://doi.org/10.1111/tpj.17111

Interpretive Summary: Understanding genetics for plant height, the iconic trait of the Green Revolution, is imperative for improving crops. This study reported the identification and characterization of the gene underlying a semi-dwarf QTL (qHT7.1) in sorghum. qHT7.1 encodes a myb transcription factor controlling the internode elongation and cell proliferation. The ortholog in maize is corresponding to the classic br1 locus. Identification of genes underlying qHT7.1 and Br1 enchanced our capacity for fine-tunning plant height for crop improvement,.

Technical Abstract: Manipulating plant height is essential for crop improvement. Plant height was reduced through breeding in wheat, rice, and grain sorghum to resist lodging and increase yield, while maintained tall for energy crop production. Here, we positionally cloned a plant height quantitative trait locus (QTL) qHT7.1 as an MYB transcription factor controlling internode elongation and cell proliferation in sorghum. The functional site of qHT7.1 was found to be a 739 bp transposable element insertion at the intronic region, causing partial missplicing with an additional exon, which contained a premature stop codon and led to a truncated amino acid sequence and an altered C terminal. Gene expression analysis revealed a dynamic pattern of qHT7.1 across development and along the internode position. The orthologue of qHT7.1 was identified to underlie the brachytic1 (br1) locus in maize. A large insertion in exon 3 and a 160 bp insertion at the promoter region were identified in the br1 mutant, while an 18 bp promoter insertion was found to be associated with plant height in a Br1 natural allele. CRISPR/Cas9 gene knockout in two maize inbreds showed significant plant height reduction. In addition, we also identified a wider distribution of the recessive qht7.1 than other dwarfing alleles (dw1, dw2, and dw3). The overall discovery enriched our understanding of plant height regulation in sorghum and maize, and enhanced our toolbox for fine-tuning plant height for crop improvement.