qSTA2-2,a novel QTL that contributes to seed starch synthesis in Zea mays L.  

作　　者：Minghao Cai Xuhui Li Zhi Liang Jie Wang Delin Li Zhipeng Yuan Riliang Gu Jianhua Wang Li Li 

机构地区：[1]State Key Laboratory of Maize Bio-breeding/Key Laboratory of Crop Heterosis Utilization,Ministry of Education/Beijing Innovation Center for Crop Seed Technology/College of Agronomy and Biotechnology,China Agricultural University,Beijing 100193,China [2]Institute of Nanfan&Seed Industry,Guangdong Academy of Science,Guangzhou 510316,China [3]Institute of Crop Sciences,Chinese Academy of Agricultural Sciences,Beijing 100081,China

出　　处：《Journal of Integrative Agriculture》2024年第4期1118-1133,共16页农业科学学报（英文版）

基　　金：supported by grants from the STI 2030-Major Projects,China(2022ZD040190101,2022ZD040190502);the National Natural Science Foundation of China(32072130,32272162 and 31701437);the Project of Sanya Yazhou Bay Science and Technology City,China(SCKJ-JYRC-2023-64);the 2115 Talent Development Program of China Agricultural University,and the China Agriculture Research System(CARS-02-13)。

摘　　要：The seed storage materials accumulate during seed development,and are essential for seed germination and seedling establishment.Here we employed two bi-parental populations of an F2:3 population developed from a cross of improved 220(I220,small seeds with low starch)and PH4CV(large seeds with high starch),as well as recombinant-inbred lines(RILs)of X178(high starch)and its improved introgression line I178(low starch),to identify the genes that control seed storage materials.We identified a total of 12 QTLs for starch,protein and oil,which explained 3.44-10.79%of the phenotypic variances.Among them,qSTA2-1 identified in F2:3 and qSTA2-2 identified in the RILs partially overlapped at an interval of 7.314-9.554 Mb,and they explained 3.44-10.21%of the starch content variation,so they were selected for further study.Fine mapping of qSTA2-2 with the backcrossed populations of ^(I220)/PH4CV in each generation narrowed it down to a 199.7 kb interval that contains 14 open reading frames(ORFs).Transcriptomic analysis of developing seeds from the near-isogenic lines(NILs)of ^(I220)/PH4CV(BC_(5)F_(2))showed that only 11 ORFs were expressed in 20 days after pollination(DAP)seeds.Five of them were upregulated and six of them were downregulated in NIL^(I220),and the differentially expressed genes(DEGs)between NIL^(I220) and NIL^(PH4CV) were enriched in starch metabolism,hormone signal transduction and glycosaminoglycan degradation.Of the eleven NIL^(I220) differential expressed ORFs,ORF4(Zm00001d002260)and ORF5(Zm00001d002261)carry 75%protein sequence similarity,both encodes an glycolate oxidase,were the possible candidates of qSTA2-2.Further analysis and validation indicated that mutation of the qSTA2-2 locus resulted in the dysfunction of ABA accumulation,the embryo/endosperm ratio and the starch and hormone levels.

关 键 词：QTL mapping seed starch transcriptomic analysis HORMONE 

分 类 号：S513[农业科学—作物学]