Natural variation in the NAC transcription factor NONRIPENING contributes to melon fruit ripening  

作　　者：Jinfang Wang Shouwei Tian Yongtao Yu Yi Ren Shaogui Guo Jie Zhang Maoying Li Haiying Zhang Guoyi Gong Min Wang Yong Xu 

机构地区：[1]National Watermelon and Melon Improvement Center,Beijing Academy of Agricultural and Forestry Sciences,Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(North China),Beijing Key Laboratory of Vegetable Germplasm Improvement,Beijing 100097,China [2]Sanya Institute,Hainan Academy of Agricultural Sciences,Haikou 572025,China

出　　处：《Journal of Integrative Plant Biology》2022年第7期1448-1461,共14页植物学报（英文版）

基　　金：financially supported by Beijing Academy of Agricultural and Forestry Sciences(KJCX20200204);the National Natural Science Foundation of China(1902034,32122077,and 32172592);the Beijing Scholar Program(YBSP019);the Sci&Tech Innovation of BAAFS(KJCX20200113);the Agriculture Innovation Consortium(BAIC10-2022);the Key Project of Science and Technology of Ningbo(2019B10007)。

摘　　要：ThThe NAC transcription factor NONRIPENING(NOR)is a master regulator of climacteric fruit ripening.Melon(Cucumis melo L.)has climacteric and nonclimacteric fruit ripening varieties and is an ideal model to study fruit ripening.Two natural CmNAC-NOR variants,the climacteric haplotype CmNAC-NOR^(S,N) and the non-climacteric haplotype CmNAC-NOR^(A,S),have effects on fruit ripening;however,their regulatory mechanisms have not been elucidated.Here,we report that a natural mutation in the transcriptional activation domain of CmNAC-NORS,Ncontributes to climacteric melon fruit ripening.CmNAC-NOR knockout in the climacteric-type melon cultivar“BYJH”completely inhibited fruit ripening,while ripening was delayed by 5-8 d in heterozygous cmnac-nor mutant fruits.CmN AC-NOR directly activated carotenoid,ethylene,and abscisic acid biosynthetic genes to promote fruit coloration and ripening.Furthermore,CmNAC-NOR mediated the transcription of the“CmNAC-NOR-CmNAC73-CmCWINV2”module to enhance flesh sweetness.The transcriptional activation activity of the climacteric haplotype CmNAC-NORS,Non these target genes was significantly higher than that of the nonclimacteric haplotype CmNAC-NOR^(A,S).Moreover,CmNAC-NORS,Ncomplementation fully rescued the non-ripening phenotype of the tomato(Solanum lycopersicum)cr-nor mutant,while CmNAC-NOR^(A,S) did not.Our results provide insight into the molecular mechanism of climacteric and non-climacteric fruit ripening in melon.

关 键 词：climacteric fruit fruit ripening MELON NAC tran-scription factor 

分 类 号：S652[农业科学—果树学]