The R2R3-MYB transcription factor GaPC controls petal coloration in cotton  

作　　者：Caiping Cai Fan Zhou Weixi Li Yujia Yu Zhihan Guan Baohong Zhang Wangzhen Guo 

机构地区：[1]State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization,Nanjing Agricultural University,Nanjing 210095,Jiangsu,China [2]Engineering Research Center of Ministry of Education for Cotton Germplasm Enhancement and Application,Nanjing Agricultural University,Nanjing 210095,Jiangsu,China [3]Department of Biology,East Carolina University,Greenville,NC 27858,USA

出　　处：《The Crop Journal》2023年第5期1319-1330,共12页作物学报（英文版）

基　　金：supported by the Fundamental Research Funds for the Central Universities(KYZZ2022003);Jiangsu Collaborative Innovation Center for Modern Crop Production project (No.10)。

摘　　要：Although a few cases of genetic epistasis in plants have been reported, the combined analysis of genetically phenotypic segregation and the related molecular mechanism remains rarely studied. Here, we have identified a gene(named GaPC) controlling petal coloration in Gossypium arboreum and following a heritable recessive epistatic genetic model. Petal coloration is controlled by a single dominant gene,GaPC. A loss-of-function mutation of GaPC leads to a recessive gene Gapc that masks the phenotype of other color genes and shows recessive epistatic interactions. Map-based cloning showed that GaPC encodes an R2R3-MYB transcription factor. A 4814-bp long terminal repeat retrotransposon insertion at the second exon led to GaPC loss of function and disabled petal coloration. GaPC controlled petal coloration by regulating the anthocyanin and flavone biosynthesis pathways. Expression of core genes in the phenylpropanoid and anthocyanin pathways was higher in colored than in white petals. Petal color was conferred by flavonoids and anthocyanins, with red and yellow petals rich in anthocyanin and flavonol glycosides, respectively. This study provides new insight on molecular mechanism of recessive epistasis,also has potential breeding value by engineering GaPC to develop colored petals or fibers for multifunctional utilization of cotton.

关 键 词：COTTON Petal color R2R3-MYB transcription factor LTR-RT insertion Flavonoid/anthocyanin biosynthesis Recessive epistasis 

分 类 号：S562[农业科学—作物学]