Paternal leakage sustains the cytoplasmic polymorphism underlying gynodioecy but remains invasible by nuclear restorers.
Paternal leakage sustains the cytoplasmic polymorphism underlying gynodioecy but remains invasible by nuclear restorers.
复制标题
父本渗漏维持了雌雄异株的细胞质多态性，但仍然不受核恢复者的影响。
DOI：
10.1086/491660
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
McCauley,DavidE
中科院分区：
文献类型：
--
作者：
Wade,MichaelJ;McCauley,DavidE
植物的细胞质雄性不育（CMS）通常导致雌雄异株种群，由雌雄同体和雄性不育雌性组成。所有的雌核发育模型都假设细胞质等位基因的母系遗传，并假定各种负频率依赖机制来维持在许多自然群体中观察到的细胞质多态性。然而，在某些植物物种中，线粒体至少偶尔通过花粉传播，这一过程称为父系泄漏。我们表明，即使是少量的父系泄漏是足以维持一个永久的，稳定的细胞质多态性。因为在雌雄异株物种中只有雌雄同体提供花粉，父本泄漏的影响是偏向的，并且更经常从非CMS雄性可育单倍型到CMS雄性不育单倍型发生。我们还表明，核恢复破坏多态性细胞质平衡，导致固定的CMS等位基因和恢复。虽然一个占主导地位的核恢复修复，它的修复速度比标准CMS模型慢得多。虽然一个稳定的细胞核多态性是可能的“匹配等位基因”核恢复，振荡到低频率的漂移损失的风险。父系渗漏通过减少CMS等位基因因漂移而丢失的机会来增强联合细胞核多态性的稳定性。
Cytoplasmic male sterility (CMS) in plants often results in gynodioecious populations, composed of hermaphrodites and male‐sterile females. All models of gynodioecy assume maternal inheritance of the cytoplasmic alleles and postulate a variety of negatively frequency‐dependent mechanisms to maintain the cytoplasmic polymorphisms observed in many natural populations. However, in some plant species, mitochondria are transmitted at least occasionally by pollen, a process called paternal leakage. We show that even a small amount of paternal leakage is sufficient to sustain a permanent, stable cytoplasmic polymorphism. Because only hermaphrodites provide pollen in gynodioecious species, the effects of paternal leakage are biased and occur more often from the non‐CMS male‐fertile haplotype to the CMS male‐sterile haplotype. We also show that a nuclear restorer disrupts the polymorphic cytoplasmic equilibrium, leading to fixation of both the CMS allele and the restorer. Although a dominant nuclear restorer fixes, it fixes much more slowly than in the standard CMS models. Although a stable cytonuclear polymorphism is possible with “matching alleles” nuclear restoration, oscillations to low frequencies present a risk of loss by drift. Paternal leakage enhances the stability of joint cytonuclear polymorphism by reducing the chance that a CMS allele is lost by drift.