Comparative screening of endosymbiotic bacteria associated with the asexual and sexual lineages of the termite Glyptotermes nakajimai

Toshihisa Yashiro,Nathan Lo

doi:10.1080/19420889.2019.1592418

Abstract

ABSTRACTMales provide opportunities both for sexual reproduction and for sex-based phenotypic differences within animal societies. In termites, the ubiquitous presence of both male and female workers and soldiers indicate that males play a critical role in colonies of these insects. However, we have recently reported all-female asexual societies in a lineage of the termite Glyptotermes nakajimai – a dramatic transition from mixed-sex to all-female asexual societies. It is known that female-producing parthenogenesis in insects can be induced by maternally inherited endosymbiotic bacteria, such as Wolbachia, Cardinium, and Rickettsia. Here, we screen for the presence of endosymbiotic bacteria in the asexual and sexual lineages of G. nakajimai. Our bacterial screening of the asexual lineage did not reveal any likely causal agents for parthenogenetic reproduction, whereas screening of the sexual lineage resulted in Wolbachia being detected. Our findings suggest that the asexuality in G. nakajimai is likely to be maintained without manipulation by endosymbiotic bacteria.

Highlights

Both males and females of many animals invariably participate in social activities [1,2]
It is known that female-producing parthenogenesis in insects can be induced by maternally inherited endosymbiotic bacteria, such as Wolbachia, Cardinium, and Rickettsia
Our findings suggest that the asexuality in G. nakajimai is likely to be maintained without manipulation by endosymbiotic bacteria

Summary

Introduction

Both males and females of many animals invariably participate in social activities [1,2]. The genetic diversity resulting from sexual reproduction is thought to provide multiple benefits, including enhanced disease resistance, and resilient division of labor [3,4]. The complete loss of males from termite lineages would result in the loss of genetic diversity and the loss of sex-based phenotypic diversity form their societies. We have recently reported asexual societies in a lineage of the termite Glyptotermes nakajimai (Isoptera: Kalotermitidae) – a dramatic transition from mixed-sex to all-female asexual societies. This finding provides evidence that males are not indispensable in advanced animal societies, regardless of whether males engage in social activities or not [7]. We examine the possibility of endosymbiont-induced host manipulations, such as PI, FM, MK, and CI in G. nakajimai

Results and discussion

90 Bacteroidetes

Methods