Department of Entomology, Agricultural Research Center-Hays, Kansas State University, Hays, KS.
Plant Protection Research Institute, Agricultural Research Center - Dokki, Giza, Egypt.
J Econ Entomol. 2020 Aug 13;113(4):1780-1785. doi: 10.1093/jee/toaa100.
We examined the ability of Coleomegilla maculata DeGeer and Hippodamia convergens Guerin-Meneville to regenerate, during pupation, a foreleg amputated in the fourth instar. Leg regeneration was complete for 80.7% of amputated H. convergens larvae, with 12.5% regenerating partially, and 6.8% showing no regeneration. Regeneration in C. maculata was 72.2% complete, 20.5% partial, and 7.2% none, but mortality following ablation was slightly higher than for H. convergens (7.4 vs. 0.6%). Ablation/regeneration caused a slight delay in pupation, but pupation time, fresh mass at emergence, and reproductive performance remained unaffected in either species. Reciprocal crosses were made between regenerated and unoperated beetles, and 12 progeny reared from the second clutch of each female in all treatments. Mating treatment affected eclosion time in H. convergens, whereas in C. maculata, larval development and pupation time were also affected. Considering all treatments, larval mortality was higher in H. convergens than in C. maculata, but lower when both H. convergens parents regenerated. Parental mating treatment did not affect adult weight in either species, but development of C. maculata progeny was faster when only the sire regenerated, and slower when the only the dame regenerated, whereas progeny of regenerated sires completed pupated faster than those sired by controls. We infer that genes activated during regeneration have pleiotropic effects with subtle, gender-specific, epigenetic consequences. If these pleiotropic effects are genetically linked to important traits, regenerative genetic elements could be conserved in coccinellids via natural selection acting on these traits, rather than on regenerative ability per se.
我们研究了Coleomegilla maculata DeGeer 和 Hippodamia convergens Guerin-Meneville 在第四龄期幼虫时，能否再生前腿断肢。H. convergens 幼虫中 80.7%的断肢完全再生，12.5%部分再生，6.8%无再生。C. maculata 的再生率为 72.2%完全再生，20.5%部分再生，7.2%无再生，但消融后的死亡率略高于 H. convergens（7.4%比 0.6%）。消融/再生略微延迟了蛹化时间，但在两种物种中，蛹化时间、出蛹时的新鲜质量和繁殖性能均未受影响。在所有处理中，对再生和未操作的甲虫进行了相互交叉，并从每个雌性的第二窝幼虫中饲养了 12 个后代。交配处理影响了 H. convergens 的出蛰时间，而在 C. maculata 中，幼虫发育和蛹化时间也受到影响。考虑到所有处理，H. convergens 的幼虫死亡率高于 C. maculata，但当两个 H. convergens 父母都再生时，幼虫死亡率较低。父母交配处理不影响两种物种的成虫体重，但当只有雄亲再生时，C. maculata 后代的发育更快，而当只有雌亲再生时，发育更慢，而由再生雄亲产生的后代比对照产生的后代更快地完成蛹化。我们推断，在再生过程中激活的基因具有多效性，具有微妙的、性别特异性的、表观遗传的后果。如果这些多效性与重要特征有关，那么再生遗传元素可以通过对这些特征的自然选择在鞘翅目昆虫中得以保留，而不是通过再生能力本身。
