Detection of the bacterial endosymbiont Wolbachia and determination of super groups present within New Zealand invertebrates : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Zoology at Massey University, Palmerston North, New Zealand
Loading...
Date
2016
DOI
Open Access Location
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Massey University
Rights
The Author
Abstract
Wolbachia is one of the most widespread intracellular bacterium on earth, estimated to infect
between 40 and 66% of arthropod species. Where significantly screened for, there is virtually no
ecosystem that Wolbachia has not managed to invade. Their impact does not come solely from their
vast distribution but in their ability to modify their hosts reproductive biology. Wolbachia is a
maternally inherited endosymbiont that can induce a range of host phenotypic responses, including
cytoplasmic incompatibility, male death, feminization, and parthenogenesis. This holds high
potential for influencing genetic diversity and speciation of its host. Wolbachia has yet to be
formally identified in New Zealand native invertebrates and therefore a gap remains in the global
understanding of Wolbachia distribution and diversity. The first aim of this thesis (Chapter 2) was
to determine if the use of high throughput sequencing (HTS) of invertebrates could be used to
identify Wolbachia sequences and establish a Wolbachia infection. seven HTS produced a positive
indication for Wolbachia sequences, with six samples originating from native New Zealand
invertebrate hosts. Once Wolbachia was detected the second aim (Chapter 2) was to determine
which super group the Wolbachia strains detected fall into. Comparing New Zealand Wolbachia
sequences to sequences obtained from GenBank, it was determined that there were two distinct
strains of Wolbachia in New Zealand hosts. One strain was related to Wolbachia super group A and
the other matched Wolbachia super group B. Wolbachia had now been detected in New Zealand,
the next aim (Chapter 3) was to determine the presence and distribution of Wolbachia across New
Zealand and across a number of native invertebrates. Wolbachia was detected in both of the main
islands of New Zealand across a number of species or putative species of ground and cave weta.
The final aim of this thesis was to determine the diversity of the Wolbachia detected and compare
that to the diversity of the ground weta complex Hemiandrus maculifrons to determine if there was
any evidence for Wolbachia affecting the genetic diversity of its host (Chapter 4). It was observed
that H. maculifrons complex was infected with both strains of Wolbachia detected in New Zealand
invertebrates. There was however not enough resolution to determine if Wolbachia has had a
significant effect on the diversity and speciation of the ground weta host.