Malone John H, Michalak P
Department of Biology, University of Texas at Arlington, Box 19498, Arlington, TX 76019, USA.
Science. 2008 Jan 4;319(5859):59. doi: 10.1126/science.1148231.
Reproductive isolation between biological species is characterized by Haldane's rule, which states that the heterogametic sex (XY or ZW) suffers the most dysfunctional effects of hybridization. It has been hypothesized that, in addition to X-linked recessive genes, Haldane's rule also reflects the faster evolution of genes related to male reproduction (faster-male evolution). We used sex-reversed hybrid Xenopus to test faster-male evolution by examining the fertility of sex-reversed individuals with the genotype of the inverse phenotypic sex. Hybrid males are sterile and hybrid females are fertile irrespective of their genotypic sex. Gene expression profiles match these adult phenotypes, and our results demonstrate that faster-male evolution is the most likely mechanism producing hybrid male sterility.
生物物种之间的生殖隔离以霍尔丹法则为特征，该法则指出异配性别（XY或ZW）在杂交中受到的功能失调影响最大。据推测，除了X连锁隐性基因外，霍尔丹法则还反映了与雄性繁殖相关基因的更快进化（雄性更快进化）。我们使用性反转的非洲爪蟾杂种，通过检查具有相反表型性别的基因型的性反转个体的生育力来测试雄性更快进化。杂种雄性不育，杂种雌性可育，无论其基因型性别如何。基因表达谱与这些成年表型相匹配，我们的结果表明，雄性更快进化是导致杂种雄性不育的最可能机制。
