Okita Ichiro, Tsuchida Koji
The United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan.
Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan.
Naturwissenschaften. 2016 Apr;103(3-4):22. doi: 10.1007/s00114-016-1349-0. Epub 2016 Feb 27.
In haplodiploid insects such as ants, male sexuals develop from unfertilised haploid eggs, while female sexuals and workers develop from fertilized diploid eggs. However, some ant species do not exchange their gene pool between sexes; both male and female sexuals are clonally produced, while workers are sexually produced. To date, three ant species, Wasmannia auropunctata, Vollenhovia emeryi, and Paratrechina longicornis, have been reported to reproduce using such reproductive systems. In this study, we reveal that in one lineage of the ant Cardiocondyla kagutsuchi, male and female sexuals are also clonally produced. In contrast to the abovementioned three species, the workers were not only sexually produced but had recombinant sequences in their nuclear internal transcribed spacer regions, although the recombinant sequences were not detected in male or female sexuals. These results suggest that the lineage likely possesses a mechanism to compensate for the reduction in genetic variation due to clonal reproduction with somatic recombination that occurs within the workers.
在诸如蚂蚁这样的单倍二倍体昆虫中,雄性有性个体由未受精的单倍体卵发育而来,而雌性有性个体和工蚁则由受精的二倍体卵发育而来。然而,一些蚂蚁物种在性别之间不进行基因库交换;雄性和雌性有性个体都是通过克隆产生的,而工蚁是有性繁殖产生的。迄今为止,已报道三种蚂蚁物种,即金刻沃氏蚁、埃氏沃氏蚁和长足盘腹蚁,使用这种生殖系统进行繁殖。在本研究中,我们揭示在卡氏心突蚁的一个谱系中,雄性和雌性有性个体同样是通过克隆产生的。与上述三种物种不同的是,工蚁不仅是有性繁殖产生的,而且在其核内转录间隔区有重组序列,尽管在雄性或雌性有性个体中未检测到重组序列。这些结果表明,该谱系可能拥有一种机制,通过工蚁体内发生的体细胞重组来补偿由于克隆繁殖导致的遗传变异减少。