Institute of Food Crops, Yunnan Academy of Agricultural Sciences, Kunming, China.
Institute of Resource Plants, Yunnan University, Kunming, 650500, China.
BMC Plant Biol. 2024 Nov 22;24(1):1110. doi: 10.1186/s12870-024-05836-5.
In this study, tropical maize germplasms were used to construct a multiparent population (MPP) to identify novel genes associated with kernel protein content. The kernel protein content was quantified using near-infrared spectroscopy (NIRS) in the MPP, which was evaluated in three different environments.
QTL mapping revealed 23 significant QTLs tightly linked to kernel protein content, with phenotypic variation ranging from 8.88 to 28.86%. Genome-wide association analysis (GWAS) identified 21 SNPs that were significantly associated with kernel protein content, with phenotypic variation explained (PVE) ranging from 4.09 to 16.15%. Through combined QTL mapping and GWAS, co-localized loci were identified, as well as two novel genes (Zm00001d034933 and Zm00001d029999) that had not been previously reported.
These genes encode pentatricopeptide repeat-containing proteins (PPR proteins), which regulate kernel endosperm development. The significant SNPs associated with these genes accounted for 23.59% of the PVE, whereas the QTLs accounted for 46.02% of the phenotypic variation. Since kernel protein synthesis and storage occur in the endosperm, this study suggests that Zm00001d034933 and Zm00001d029999 may potentially regulate kernel protein content in maize.
本研究利用热带玉米种质资源构建多亲本群体（MPP），以鉴定与籽粒蛋白含量相关的新基因。采用近红外光谱（NIRS）对 MPP 中的籽粒蛋白含量进行定量分析，并在三个不同环境下进行评价。
QTL 作图鉴定出 23 个与籽粒蛋白含量紧密连锁的显著 QTL，表型变异范围为 8.88%至 28.86%。全基因组关联分析（GWAS）鉴定出 21 个与籽粒蛋白含量显著相关的 SNP，表型变异解释率（PVE）范围为 4.09%至 16.15%。通过联合 QTL 作图和 GWAS，鉴定出了共定位的基因座，以及两个以前未报道过的新基因（Zm00001d034933 和 Zm00001d029999）。
这些基因编码五肽重复蛋白（PPR 蛋白），调节籽粒胚乳发育。与这些基因相关的显著 SNP 占 PVE 的 23.59%，而 QTL 占表型变异的 46.02%。由于籽粒蛋白的合成和储存发生在胚乳中，因此本研究表明 Zm00001d034933 和 Zm00001d029999 可能潜在地调节玉米籽粒蛋白含量。
