Jeong G, Stouthamer R
Laboratory of Entomology, Wageningen University, 6700EH, Wageningen, The Netherlands.
Heredity (Edinb). 2005 Apr;94(4):402-7. doi: 10.1038/sj.hdy.6800617.
A lepidopteran egg parasitoid species Telenomus nawai consists of two distinct populations with different reproductive modes. One is a completely thelytokous population consisting of females only, whereas the other displays arrhenotokous reproduction where fertilized eggs develop into diploid females and unfertilized eggs into haploid males. Thelytoky in T. nawai is caused by a bacterial symbiont, the parthenogenesis-inducing (PI) Wolbachia. Recent theoretical studies have shown that when a PI-Wolbachia is spreading in a population, mutations that allow uninfected females to produce more male offspring will spread rapidly eventually becoming fixed. The consequence of such a mutation is that sexual reproduction is no longer successful in infected females. Here we determine the genetic basis of the females' inability to reproduce sexually by introgressing the genome of a thelytokous line into an arrhenotokous line. The results suggest that the mutations are recessive and inherited either as a single-locus major gene with some modifiers, or as two partially linked loci.
一种鳞翅目卵寄生蜂——那波长尾小蜂（Telenomus nawai）由两个具有不同生殖模式的不同种群组成。一个是完全产雌孤雌生殖的种群，仅由雌性组成，而另一个表现为产雄孤雌生殖，受精卵发育成二倍体雌性，未受精卵发育成单倍体雄性。那波长尾小蜂的产雌孤雌生殖是由一种细菌共生体——诱导孤雌生殖（PI）的沃尔巴克氏体引起的。最近的理论研究表明，当一种PI-沃尔巴克氏体在种群中传播时，允许未感染雌性产生更多雄性后代的突变将迅速传播并最终固定下来。这种突变的结果是，有性生殖在受感染的雌性中不再成功。在这里，我们通过将产雌孤雌生殖品系的基因组渗入产雄孤雌生殖品系，确定了雌性无法进行有性生殖的遗传基础。结果表明，这些突变是隐性的，要么作为一个带有一些修饰基因的单基因座主基因遗传，要么作为两个部分连锁的基因座遗传。
