Edwards A M, Cameron E Z, Pereira J C, Wapstra E, Ferguson-Smith M A, Horton S R, Thomasson K
School of Biological Sciences, University of Tasmania, Hobart, Tasmania, Australia; Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
School of Biological Sciences , University of Tasmania , Hobart, Tasmania , Australia.
R Soc Open Sci. 2016 Jul 13;3(7):160210. doi: 10.1098/rsos.160210. eCollection 2016 Jul.
Empirical tests of adaptive maternal sex allocation hypotheses have presented inconsistent results in mammals. The possibility that mothers are constrained in their ability to adjust sex ratios could explain some of the remaining variation. Maternal effects, the influence of the maternal phenotype or genotype on her developing offspring, may constrain sex allocation through physiological changes in response to the gestational environment. We tested if maternal effects constrain future parental sex allocation through a lowered gestational stress environment in laboratory mice. Females that experienced lowered stress as embryos in utero gave birth to female-biased litters as adults, with no change to litter size. Changes in offspring sex ratio was linked to peri-conceptual glucose, as those females that had increasing blood glucose peri-conceptionally gave birth to litters with a higher male to female sex ratio. There was, however, no effect of the lowered prenatal stress for developing male embryos and their sperm sex ratio when adult. We discuss the implications of maternal effects and maternal stress environment on the lifelong physiology of the offspring, particularly as a constraint on later maternal sex allocation.
在哺乳动物中，对适应性母体性别分配假说的实证检验结果并不一致。母亲在调整性别比例方面的能力受到限制，这一可能性或许可以解释部分剩余的变异性。母体效应，即母体表型或基因型对其发育中后代的影响，可能会通过对妊娠环境做出反应的生理变化来限制性别分配。我们在实验室小鼠中测试了母体效应是否通过降低妊娠应激环境来限制未来亲代的性别分配。在子宫内作为胚胎时经历较低应激的雌性成年后产下雌性偏多的窝仔，窝仔大小没有变化。后代性别比例的变化与受孕前后的葡萄糖有关，因为那些在受孕前后血糖升高的雌性产下的窝仔中雄雌性别比例更高。然而，产前应激降低对发育中的雄性胚胎及其成年后的精子性别比例没有影响。我们讨论了母体效应和母体应激环境对后代终身生理的影响，特别是作为对后期母体性别分配的一种限制。
