Meiotic recombination dramatically decreased in thelytokous queens of the little fire ant and their sexually produced workers.
Meiotic recombination dramatically decreased in thelytokous queens of the little fire ant and their sexually produced workers.
复制标题
小火蚁的产卵蚁后及其有性生殖的工蚁的减数分裂重组显着减少。
DOI：
10.1093/molbev/msr082
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发表时间：
2011
影响因子：
10.7
通讯作者：
A. Estoup
中科院分区：
文献类型：
--
作者：
O. Rey;A. Loiseau;B. Facon;J. Foucaud;J. Orivel;J. Cornuet;S. Robert;G. Dobigny;J. Delabie;C. Mariano;A. Estoup
小火蚁（Wasmannia auropunctata）具有独特的繁殖系统多态性。典型的单倍-二倍体有性生殖发生在一些种群中，而在另一些种群中，蜂王和雄蜂进行克隆生殖。工蜂是有性繁殖的，在无性繁殖和有性繁殖的种群中都是不育的。克隆谱系的进化命运在很大程度上取决于允许生殖个体将其基因组传递给后代的潜在机制。我们使用了几个皇后后代的数据集，以估计与重组事件在33个微卫星位点的thelytokous孤雌生殖皇后谱系从杂合性到纯合性的过渡率，并比较这些利率与各种孤雌生殖机制下的理论预期。然后，我们使用性产生的工人家庭定义这33个位点的连锁群，并比较减数分裂重组率在有性和孤雌生殖皇后。我们的研究结果表明，从克隆种群的皇后繁殖的自融孤雌生殖与中央融合。这些相同的孤雌生殖皇后产生正常分离的减数分裂卵母细胞的工人，显示低得多的重组率（由一个因素的45）比工人产生的性皇后。这些低重组率也涉及孤雌生殖生产的女王后代，所示的非常低的过渡率从杂合性纯合性观察（从0%到2.8%）。我们认为，结合自体融合与中央融合和重组率的大幅下降，使克隆皇后受益于thelytoky，同时避免潜在的近交衰退造成的杂合性丧失在自体融合。在不育的工人，重组率的强烈下降也可能有利于保护随着时间的推移，一些coadapted等位基因的相互作用的染色体内，可能赋予一个适应性优势，在栖息地受到人类活动的干扰，在克隆种群的W。大多数都有金斑蝶。
The little fire ant, Wasmannia auropunctata, displays a peculiar breeding system polymorphism. Classical haplo-diploid sexual reproduction between reproductive individuals occurs in some populations, whereas, in others, queens and males reproduce clonally. Workers are produced sexually and are sterile in both clonal and sexual populations. The evolutionary fate of the clonal lineages depends strongly on the underlying mechanisms allowing reproductive individuals to transmit their genomes to subsequent generations. We used several queen-offspring data sets to estimate the rate of transition from heterozygosity to homozygosity associated with recombination events at 33 microsatellite loci in thelytokous parthenogenetic queen lineages and compared these rates with theoretical expectations under various parthenogenesis mechanisms. We then used sexually produced worker families to define linkage groups for these 33 loci and to compare meiotic recombination rates in sexual and parthenogenetic queens. Our results demonstrate that queens from clonal populations reproduce by automictic parthenogenesis with central fusion. These same parthenogenetic queens produce normally segregating meiotic oocytes for workers, which display much lower rates of recombination (by a factor of 45) than workers produced by sexual queens. These low recombination rates also concern the parthenogenetic production of queen offspring, as indicated by the very low rates of transition from heterozygosity to homozygosity observed (from 0% to 2.8%). We suggest that the combination of automixis with central fusion and a major decrease in recombination rates allows clonal queens to benefit from thelytoky while avoiding the potential inbreeding depression resulting from the loss of heterozygosity during automixis. In sterile workers, the strong decrease of recombination rates may also facilitate the conservation over time of some coadapted allelic interactions within chromosomes that might confer an adaptive advantage in habitats disturbed by human activity, where clonal populations of W. auropunctata are mostly found.
影响因子：
3.1
作者：
KONDRASHOV, AS
通讯作者：
KONDRASHOV, AS