Genomics of sex allocation in the parasitoid wasp Nasonia vitripennis

Abstract

Background: Whilst adaptive facultative sex allocation has been widely studied at the phenotypic level across a broad range of organisms, we still know remarkably little about its genetic architecture. Here, we explore the genome-wide basis of sex ratio variation in the parasitoid wasp Nasonia vitripennis, perhaps the best studied organism in terms of sex allocation, and well known for its response to local mate competition. Results: We performed a genome-wide association study (GWAS) for single foundress sex ratios using iso-female lines derived from the recently developed outbred N. vitripennis laboratory strain HVRx. The iso-female lines capture a sample of the genetic variation in HVRx and we present them as the first iteration of the Nasonia vitripennis Genome Reference Panel (NVGRP 1.0). This panel provides an assessment of the standing genetic variation for sex ratio in the study population. Using the NVGRP, we discovered a cluster of 18 linked SNPs, encompassing 9 annotated loci associated with sex ratio variation. Furthermore, we found evidence that sex ratio has a shared genetic basis with clutch size on three different chromosomes. Conclusions: Our approach provides a thorough description of the quantitative genetic basis of sex ratio variation in Nasonia at the genome level and reveals a number of interrelated candidate loci underlying sex allocation regulation.

The emergence of ecotypes in a parasitoid wasp: a case of incipient sympatric speciation in Hymenoptera?

“…Note that this approach is different from generating artificial isofemale lines, which are used to produce genetically homogenous individuals to study the genetics of certain traits (e.g. [ 136 ]). Strains from nest boxes and from carrion were kept in different rooms at constant light.…”

Genetic, morphometric, and molecular analyses of interspecies differences in head shape and hybrid developmental defects in the wasp genus Nasonia

“…Aside from forward genetic approaches described above, Nasonia is amenable to reverse genetic approaches, such as RNA interference ( Lynch and Desplan 2006 ; Werren et al 2009 ). The utility of the Nasonia genus model system to identify the genetic basis of a wide variety of biological traits of evolutionary importance has been amply demonstrated in recent years ( Gadau et al 2002 ; Verhulst et al 2010 ; Loehlin and Werren 2012 ; Brucker and Bordenstein 2013 ; Niehuis et al 2013 ; Hoedjes et al 2014 ; Martinson et al 2017 ; Funkhouser-Jones et al 2018 ; Pannebakker et al 2020 ; Zou et al 2020 ).…”

Chemical and population genetic analysis show no evidence of ecotype formation in a European population of the parasitoid wasp Nasonia vitripennis

“…The strains used in Malec et al (2021) had been cultured in the laboratory for over 20 generations. However, maternal Wolbachia transmission is not 100% (Hoffmann et al, 1990;Turelli et al, 1992) and prolonged laboratory rearing has been reported to result in loss of the Wolbachia infection in N. vitripennis strains (Pannebakker et al, 2020). This is crucial, as Wolbachia-infected males are incompatible with Wolbachiauninfected females, leading to different degrees of offspring reduction (Breeuwer and Werren, 1990;Bordenstein and Werren, 1998;Bordenstein et al, 2001).…”

“…Giesbers et al, 2013;Bell and Bordenstein, 2022) and evolutionary genetics (e.g. van de Zande et al, 2014;Pannebakker et al, 2020). Its most well-known and cosmopolitan species, Nasonia vitripennis, has been proposed to be differentiated into two ecotypes distinguishable by their respective microhabitats (Schröder, 2000;Malec et al, 2021; Figure 1).…”