Join our online ASP Seminar Series Friday 17 July @1pm AEST, featuring Vincent C. Duru, BUA Joint PhD Scholar (BER-MEL Network) The University of Melbourne presenting “First in vitro feeding of an Australian wildlife tick, Ixodes hirsti, provides insights into tick morphology and microbiome” and Nicole (Nic) Addams, PhD Student with the Jex Lab, Walter and Eliza Hall Institute presenting “The eukaryotic-emerged spliceosome and spliceosomal introns in the early-diverging protist pathogen Giardia duodenalis” with co-chairs Ben Liffner, University of Adelaide and Grace Peters, University of New South Wales.
Please register online using this link for your unique passcode to join the seminar. After registering, you will receive a confirmation email containing information about joining the meeting.
Vincent is a Berlin Universities Alliance Doctoral Scholar (BUA MEL-BER Network) completing a Joint PhD between Freie Universität Berlin and the University of Melbourne. Over the past three years, he’s been persuading ticks to feed in the lab (yes, that’s basically what I do!) developing in vitro models to study tick–pathogen interactions in Ixodes ticks. Originally from Nigeria, he holds a BSc in Parasitology & Entomology and an MSc in Public Health Biotechnology. His research aims to develop innovative strategies for studying the biology and transmission dynamics of ticks and tick-borne pathogens.
Title: First in vitro feeding of an Australian wildlife tick, Ixodes hirsti, provides insights into tick morphology and microbiome
Abstract
Artificial tick feeding systems (ATFS) provide ethical alternatives to in vivo models for studying tick biology, yet their application remains largely restricted to a few species. Ixodes hirsti, an Australian marsupial tick, remains understudied due to challenges in maintaining its life cycle under laboratory conditions. We report the first successful in vitro feeding of Ixodes hirsti larvae, coupled with microbiome profiling and morphological characterization of moulted nymphs. Larvae were fed through silicone membranes supplemented with kangaroo hair and/or hair extract. Hair extract significantly increased attachment (71%; p = 0.001), while kangaroo hair improved engorgement time and weight. Blood feeding reduced microbial diversity, increased microbiome variability (p < 0.001), and enriched Stenotrophomonas. This host-free platform enables controlled studies of Australian tick biology and tick–microbe interactions.
Nic Addams is a PhD candidate at the WEHI, where she is a member of the Jex Lab. Before commencing her doctoral research, she earned her Masters in plant science. Her broader research interests include molecular evolution and systems biology. Outside of the lab, Nic has far too many hobbies and cats.
Talk title:
“The eukaryotic-emerged spliceosome and spliceosomal introns in the early-diverging protist pathogen Giardia duodenalis”
Authors: Nic Addams1, Alex Lam1, Balu Balan1, Aaron Jex1,2
1. Walter and Eliza Hall Institute of Medical Research, Department of Infection and Global Health, The University of Melbourne, Victoria, Australia
2. The University of Melbourne, Faculty of Science, Melbourne Veterinary School, Victoria, Australia
Abstract:
Alternative splicing is a major mediator of eukaryotic gene expression, operating co-transcriptionally and post-transcriptionally to influence cellular function, development, and differentiation. During alternative splicing, trans-acting factors interact with cis-elements within pre-mRNA transcripts to produce divergent proteoforms. In eukaryotes, most trans-acting factors work in conjunction as the spliceosome, a dynamic ribonucleoprotein complex comprised of catalytic RNAs and hundreds of proteins. Previous studies sought to comprehend the intricate mechanisms of the spliceosome within a simplistic system, utilising the model organism Saccharomyces cerevisiae. However, there exists a eukaryote more basal than yeast – Giardia duodenalis, an intron-poor enteric parasite, evolved over 500 million years earlier. Our bioinformatic analyses indicated that splicing proteins in Giardia are minimal, both in number and structure. This raises the question: In deeply-branching eukaryotes such as Giardia, does splicing occur spliceosomally or via a more primordial method? To understand the system of splicing in Giardia, we are conducting an in vitro splicing assay involving both conventional and chimeric intron-containing transcripts. In parallel, we are establishing a nuclear proteome to locate and validate the suite of Giardia splicing proteins. By implementing a multiomic approach, our study offers a glimpse into the origins and evolution of alternative splicing following the inception of eukaryotic life.
Our ASP Online Seminar Series image is created by Thorey Jonsdottir.
