Cloning of wheat keto-acyl thiolase 2B reveals a role of jasmonic acid in grain weight determination

• Published in: Nature communications Vol. 11; no. 1; p. 6266
• Main Authors: Chen, Yun, Yan, Yan, Wu, Tian-Tian, Zhang, Guo-Liang, Yin, Huanran, Chen, Wei, Wang, Shuangshuang, Chang, Fang, Gou, Jin-Ying
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 08-12-2020; Nature Publishing Group; Nature Portfolio
• Subjects: 631/208/8; 631/449/1741/2671; 631/61/447/8; 64; Abscisic acid; Abscisic Acid - metabolism; Acetyl-CoA C-Acyltransferase - genetics; Acetyl-CoA C-Acyltransferase - isolation & purification; Acetyl-CoA C-Acyltransferase - metabolism; Chlorophyll; Chlorophyll - metabolism; Cloning; Cloning, Molecular; Codon, Nonsense; Crop yield; Cyclopentanes - metabolism; Edible Grain - physiology; Grain; Humanities and Social Sciences; Jasmonic acid; multidisciplinary; Mutants; Mutation; Oxidation; Oxylipins - metabolism; Phenotypes; Plant Leaves - metabolism; Plant Proteins - genetics; Plant Proteins - isolation & purification; Plant Proteins - metabolism; Plants, Genetically Modified; Quantitative Trait Loci; Recombinant Proteins - genetics; Recombinant Proteins - isolation & purification; Recombinant Proteins - metabolism; Science; Science (multidisciplinary); Sucrose; Sugar; Synthesis; Thiolase; Triticale; Triticum - physiology; Weight; Wheat
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-20133-z

Grain weight (GW) is one of the component traits of wheat yield. Existing reports have shown that multiple phytohormones are involved in the regulation of GW in different crops. However, the potential role of jasmonic acid (JA) remains unclear. Here, we report that
triticale grain weight 1
(
tgw1
) mutant, with marked reductions in both GW and JA content, is caused by a premature stop mutation in
keto-acyl thiolase 2B
(
KAT-2B
) involved in β-oxidation during JA synthesis.
KAT-2B
overexpression increases GW in wild type and boosts yield. Additionally,
KAT-2B
compliments the grain defect in
tgw1
and rescues the lethal phenotype of the
Arabidopsis kat2
mutant in a sucrose-free medium. Despite the suppression of JA synthesis in
tgw1
mutant, ABA synthesis is upregulated, which is accompanied by enhanced expression of
SAG3
and reduction of chlorophyll content in leaves. Together, these results demonstrate a role of the JA synthetic gene
KAT-2B
in controlling GW and its potential application value for wheat improvement.
It has been reported that several phytohormones are involved in the regulation of grain weight, but the role of jasmonic acids (JA) remains elusive. Here, via bulked segregant analysis (BSA)-based cloning, the authors show keto-acyl thiolase 2B involved in β-oxidation during JA synthesis is a positive regulator of wheat grain weight.