Section of Molecular Cell and Developmental Biology, Center for Computational Biology and Bioinformatics, and Institute for Cellular and Molecular Biology, The University of Texas at Austin, One University Station A4800, Austin, TX 78712, USA.
Trends Plant Sci. 2010 Feb;15(2):57-71. doi: 10.1016/j.tplants.2009.12.003. Epub 2010 Jan 18.
Hybrids such as maize (Zea mays) or domestic dog (Canis lupus familiaris) grow bigger and stronger than their parents. This is also true for allopolyploids such as wheat (Triticum spp.) or frog (i.e. Xenopus and Silurana) that contain two or more sets of chromosomes from different species. The phenomenon, known as hybrid vigor or heterosis, was systematically characterized by Charles Darwin (1876). The rediscovery of heterosis in maize a century ago has revolutionized plant and animal breeding and production. Although genetic models for heterosis have been rigorously tested, the molecular bases remain elusive. Recent studies have determined the roles of nonadditive gene expression, small RNAs, and epigenetic regulation, including circadian-mediated metabolic pathways, in hybrid vigor, which could lead to better use and exploitation of the increased biomass and yield in hybrids and allopolyploids for food, feed, and biofuels.
杂种，如玉米（Zea mays）或家犬（Canis lupus familiaris），比它们的父母生长得更大更强壮。这种情况也适用于含有来自不同物种的两套或更多套染色体的异源多倍体，如小麦（Triticum spp.）或青蛙（即 Xenopus 和 Silurana）。这种现象被称为杂种优势或杂种优势，是由查尔斯·达尔文（Charles Darwin）（1876 年）系统描述的。一个世纪前，玉米杂种优势的重新发现彻底改变了植物和动物的繁殖和生产。尽管杂种优势的遗传模型已经经过严格的测试，但分子基础仍然难以捉摸。最近的研究确定了非加性基因表达、小 RNA 和表观遗传调控（包括生物钟介导的代谢途径）在杂种优势中的作用，这可能导致更好地利用和开发杂种和异源多倍体的增加的生物量和产量，用于食品、饲料和生物燃料。
