研究人员发现，玉米的定量性状位点KRN2和它的水稻直系亲属OsKRN2经历了趋同选择。这些同源基因编码WD40蛋白，并与一个功能未知的基因DUF1644相互作用，对两种作物的籽粒数进行负向调节。玉米中KRN2或水稻中OsKRN2的基因敲除分别增加了10%和8%的粮食产量，而在其他农艺性状方面没有明显的权衡。此外，全基因组扫描确定了490对在玉米和水稻进化过程中经历了趋同选择的正交基因，这些基因富集于两条共同的分子通路。KRN2与其他趋同选择的基因一起，为未来的作物改良提供了一个很好的靶标。
据悉，更好地了解作物之间的趋同选择的程度可以大大改善育种计划。
附：英文原文
Title: Convergent selection of a WD40 protein that enhances grain yield in maize and rice
Author: Wenkang Chen, Lu Chen, Xuan Zhang, Ning Yang, Jianghua Guo, Min Wang, Shenghui Ji, Xiangyu Zhao, Pengfei Yin, Lichun Cai, Jing Xu, Lili Zhang, Yingjia Han, Yingni Xiao, Gen Xu, Yuebin Wang, Shuhui Wang, Sheng Wu, Fang Yang, David Jackson, Jinkui Cheng, Saihua Chen, Chuanqing Sun, Feng Qin, Feng Tian, Alisdair R. Fernie, Jiansheng Li, Jianbing Yan, Xiaohong Yang
Issue&Volume: 2022-03-25
Abstract: A better understanding of the extent of convergent selection among crops could greatly improve breeding programs. We found that the quantitative trait locus KRN2 in maize and its rice ortholog, OsKRN2, experienced convergent selection. These orthologs encode WD40 proteins and interact with a gene of unknown function, DUF1644, to negatively regulate grain number in both crops. Knockout of KRN2 in maize or OsKRN2 in rice increased grain yield by ~10% and ~8%, respectively, with no apparent trade-offs in other agronomic traits. Furthermore, genome-wide scans identified 490 pairs of orthologous genes that underwent convergent selection during maize and rice evolution, and these were enriched for two shared molecular pathways. KRN2, together with other convergently selected genes, provides an excellent target for future crop improvement.
DOI: abg7985
Source: https://www.science.org/doi/10.1126/science.abg7985