Haldane's rule: Hybrid sterility affects the heterogametic sex first because sexual differentiation is on the path to species differentiation
Haldane's rule: Hybrid sterility affects the heterogametic sex first because sexual differentiation is on the path to species differentiation
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DOI：
10.1006/jtbi.2000.2028
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发表时间：
2000-06-07
影响因子：
2
通讯作者：
Forsdyke, DR
中科院分区：
文献类型：
--
作者：
Forsdyke, DR
防止重组是保持种间表型分化和种内性表型分化的必要条件。对于物种分化（物种形成），阻止重组的隔离屏障可能是前合子屏障（配子转移屏障）或后合子屏障（要么是导致杂种不育的发育屏障，要么是导致杂种不育的染色体配对屏障）。不育障碍通常是首先出现的，虽然最初通常只在异种配子性别中表现出来（霍尔丹规则），但最终在两性中都表现出来。对于性别分化来说，第一个也是唯一的障碍是染色体配对，这通常适用于异种配子的性别。对于影响性别分化的性染色体区域，一定有某种类似于亲缘物种杂交时产生杂交不育的过程。对霍尔丹规则的解释通常假设，染色体配对障碍导致物种进化分化是由于基因产物（“基因”）或基因产物集（“多基因”）之间的不相容，而不是染色体本身（“染色体”）之间的不相容。然而，如果促进早期性别分化的染色体不相容也可能有助于早期物种形成的过程，那么在异配型性别中，物种形成将迈出一步。因此，当“品种”杂交时，表现为杂交不育的早期物种形成，将出现在异配子性的最早阶段，甚至在具有同态性染色体的属中也是如此（霍尔丹杂交不育规则）。相比之下，有人提出Haldane的杂交种不生存规则需要剂量补偿的差异，因此不适用于具有同态性染色体的属。(C) 2000年学术出版社。
Prevention of recombination is needed to preserve both phenotypic differentiation between species and sexual phenotypic differentiation within species. For species differentiation (speciation), isolating barriers preventing recombination may be pre-zygotic (gamete transfer barriers), or post-zygotic (either a developmental barrier resulting in hybrid inviability, or a chromosomal-pairing barrier resulting in hybrid sterility). The sterility barrier is usually the first to appear and, although often initially only manifest in the heterogametic sex (Haldane's rule), is finally manifest in both sexes. For sexual differentiation, the first and only barrier is chromosomal-pairing, and always applies to the heterogametic sex. For regions of sex chromosomes affecting sexual differentiation there must be something analogous to the process generating the hybrid sterility seen when allied species cross. Explanations for Haldane's rule have generally assumed that the chromosomal-pairing barrier initiating evolutionary divergence into species is due to incompatibilities between gene products ("genic"), or sets of gene products ("polygenic"), rather than between chromosomes per se ("chromosomal"). However, if chromosomal incompatibilities promoting incipient sexual differentiation could also contribute to the process of incipient speciation, then a step towards speciation would have been taken in the heterogametic sex. Thus, incipient speciation, manifest as hybrid sterility when "varieties" are crossed, would appear at the earliest stage in the heterogametic sex, even in genera with homomorphic sex chromosomes (Haldane's rule for hybrid sterility). In contrast, it has been proposed that Haldane's rule for hybrid inviability needs differences in dosage compensation, so could not apply to genera with homomorphic sex chromosomes. (C) 2000 Academic Press.