Smith Nicholas M A, Yagound Boris, Remnant Emily J, Foster Charles S P, Buchmann Gabriele, Allsopp Michael H, Kent Clement F, Zayed Amro, Rose Stephen A, Lo Kitty, Ashe Alyson, Harpur Brock A, Beekman Madeleine, Oldroyd Benjamin P
Behaviour and Genetics of Social Insects Laboratory, The University of Sydney, Sydney, NSW, Australia.
Evolutionary and Integrative Zoology Laboratory, The University of Sydney, Sydney, NSW, Australia.
Mol Ecol. 2020 Apr;29(8):1523-1533. doi: 10.1111/mec.15419. Epub 2020 Apr 24.
The Kinship Theory of Genomic Imprinting (KTGI) posits that, in species where females mate with multiple males, there is selection for a male to enhance the reproductive success of his offspring at the expense of other males and his mating partner. Reciprocal crosses between honey bee subspecies show parent-of-origin effects for reproductive traits, suggesting that males modify the expression of genes related to female function in their female offspring. This effect is likely to be greater in the Cape honey bee (Apis mellifera capensis), because a male's daughters have the unique ability to produce female offspring that can develop into reproductive workers or the next queen without mating. We generated reciprocal crosses between Capensis and another subspecies and used RNA-seq to identify transcripts that are over- or underexpressed in the embryos, depending on the parental origin of the gene. As predicted, 21 genes showed expression bias towards the Capensis father's allele in colonies with a Capensis father, with no such bias in the reciprocal cross. A further six genes showed a consistent bias towards expression of the father's allele across all eight colonies examined, regardless of the direction of the cross. Consistent with predictions of the KTGI, six of the 21 genes are associated with female reproduction. No gene consistently showed overexpression of the maternal allele.
基因组印记的亲缘关系理论（KTGI）认为，在雌性与多个雄性交配的物种中，存在一种选择，即雄性会以牺牲其他雄性及其交配伴侣为代价，来提高自己后代的繁殖成功率。蜜蜂亚种之间的正反交显示出繁殖性状的亲本来源效应，这表明雄性会改变其雌性后代中与雌性功能相关基因的表达。这种效应在海角蜜蜂（Apis mellifera capensis）中可能更大，因为雄性的女儿具有独特的能力，能够产生无需交配就能发育成生殖工蜂或下一任蜂王的雌性后代。我们进行了海角蜜蜂与另一个亚种之间的正反交，并使用RNA测序来鉴定根据基因的亲本来源在胚胎中表达上调或下调的转录本。正如预测的那样，在有海角蜜蜂父亲的蜂群中，有21个基因表现出对海角蜜蜂父亲等位基因的表达偏向，而在反交中则没有这种偏向。另外六个基因在所有八个被检测的蜂群中都表现出对父亲等位基因表达的一致偏向，无论杂交方向如何。与KTGI的预测一致，这21个基因中有六个与雌性繁殖相关。没有基因始终表现出母本等位基因的过表达。
