Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland.
Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland
Proc Natl Acad Sci U S A. 2020 Jul 21;117(29):17130-17134. doi: 10.1073/pnas.2003282117. Epub 2020 Jul 7.
Supergenes underlie striking polymorphisms in nature, yet the evolutionary mechanisms by which they arise and persist remain enigmatic. These clusters of linked loci can spread in populations because they captured coadapted alleles or by selfishly distorting the laws of Mendelian inheritance. Here, we show that the supergene haplotype associated with multiple-queen colonies in Alpine silver ants is a maternal effect killer. All eggs from heterozygous queens failed to hatch when they did not inherit this haplotype. Hence, the haplotype specific to multiple-queen colonies is a selfish genetic element that enhances its own transmission by causing developmental arrest of progeny that do not carry it. At the population level, such transmission ratio distortion favors the spread of multiple-queen colonies, to the detriment of the alternative haplotype associated with single-queen colonies. Hence, selfish gene drive by one haplotype will impact the evolutionary dynamics of alternative forms of colony social organization. This killer hidden in a social supergene shows that large nonrecombining genomic regions are prone to cause multifarious effects across levels of biological organization.
超级基因在自然界中构成了显著的多态性，然而它们产生和持续存在的进化机制仍然是个谜。这些连锁基因簇可以在种群中传播，因为它们捕获了协同适应的等位基因，或者通过自私地扭曲孟德尔遗传定律。在这里，我们表明与阿尔卑斯银蚁多蜂王群体相关的超级基因座是一种母性效应杀手。当异质合子蜂王没有遗传这种单倍型时，所有的卵子都无法孵化。因此，多蜂王群体特有的单倍型是一种自私的遗传因子，通过导致不携带它的后代发育停滞，从而增强自身的传播。在种群水平上，这种传递率的扭曲有利于多蜂王群体的传播，而不利于与单蜂王群体相关的替代单倍型。因此，一种单倍型的自私基因驱动将影响群体社会组织的替代形式的进化动态。这种隐藏在社会超级基因中的杀手表明，大型非重组基因组区域容易在多个层次的生物组织中产生多种影响。
