Evolution of axis specification in annelid worms
- Supervisor: Dr Chema Martin
- Deadline: 21st March 2018
- Funding: QMUL (UK/EU only)
Animals display astoundingly diverse morphologies. However, nearly all animals originate during a process called embryogenesis, in which a single cell – the zygote – develops into a multicellular complex organism. This is a stepwise process, where the zygote first divides and defines a primary set of spatially organised cells, which later on differentiate into the wealth of cell types, tissues, and organs of adult animals. As such, changes in animal embryogenesis can promote variation in adult phenotypes, and thus the evolution of the wondrous diversity of animal forms. Which cellular and genetic mechanisms control animal embryogenesis? How do these mechanisms evolve over time? How does its change contribute to animal evolution? My lab investigates how the diversity of early embryonic strategies found in Spiralia – one of the largest groups in animal phylogeny, including clades such as molluscs and annelids – informs these questions.
Spiralia is defined by the presence of spiral cleavage, a highly stereotypical early embryonic program shared by at least seven phyla, which otherwise exhibit a tremendous morphological diversity. Importantly, embryos with spiral cleavage specify their early cell fates either conditionally or autonomously. In conditional spiral cleaving embryos, bilateral symmtery is specified at ~32–64-cell stage by inductive cell-cell interactions. In autonomous spiral cleaving embryos, the differential segregation of maternal cytoplasmatic mRNAs already at the 4-cell stage specifies bilateral symmtery. The phylogenetic distribution of these two embryonic modes in Spiralia suggests that the conditional development is an ancestral character, and that the autonomous mode evolved convergently multiple times. However, how spiralian lineages repeatedly shifted from conditional to autonomous specification modes is unclear, largely because the mechanisms controlling these developmental strategies are still poorly characterized.
A PhD studentship is available for a project on the study of axis specification in the marine annelid O. fusiformis. This species occupies a key phylogenetic position as the sister lineage to all remaining annelids, and it has recently proven very informative for the study of animal development and evolution (Martin-Duran et al. 2017 Nat Ecol Evol; Martin-Duran et al. 2018 Nature). The project will characterize cellular dynamics during spiral cleavage with high-resolution live microscopy, and investigate the genomic and molecular mechanisms involved in the establishment of bilateral symmetry in this annelid species. The lab also has other annelid species in culture, and thus the successful applicant will also have some opportunity to develop his/her own research directions based on interests and skills, given that these fall within the expertise of the supervisor and align with on-going research projects within the group.
We are looking for a highly self-motivated and enthusiastic candidate with a strong interest in evolutionary developmental biology, some research experience in molecular biology, and an aptitude with computers. The project will involve both experimental and computational approaches, as well as molecular biology and microscopy techniques. The successful applicant will also have the opportunity to present their work at national and international conferences, and to collaborate with other research groups at an international and interdisciplinary level. The successful candidate will need to be able to work independently, as well as part of a team. While training will be available, the student will also be expected to develop proficiency in molecular techniques (e.g. gene cloning, in situ hybridization, immunohistochemistry, epigenomic approaches), live microscopy, and computational analyses of next-generation sequencing datasets.
Location: Our group is one of several in Evolutionary Genetics and Organismal Biology within Queen Mary’s School of Biological and Chemical Sciences. The School benefits from state-of-the-art equipment and expertise in molecular biology, next-generation sequencing technologies, genomics and bioinformatics. Queen Mary is a Russell Group University, a college of the University of London and located in London’s vibrant East End (10 min bicycle ride to Tower Bridge; 10 min walking to Victoria Park; 30 min walking to Shoreditch nightlife).
The studentship is open to UK and EU nationals. It will cover tuition fees and provide an annual tax-free maintenance allowance for 3 years at Research Councils UK rates (£16,553 in 2017/18).
Eligibility and Applying
Applications are invited from candidates with, or expecting to be awarded, a degree (UK 1st or 2:1 or equivalent qualification) in a relevant area (e.g. biology, biochemistry, biomedicine). Although not essential, ideally applicants will have a Master’s degree, or appropriate relevant work experience. Experience in molecular biology, microscopy, and/or bioinformatics are desirable.
Informal enquiries are encouraged and can be made by email to Dr. Jose M. (Chema) Martin-Duran (firstname.lastname@example.org). For more information about Dr. Martin’s research profile, please see https://scholar.google.no/citations?user=aLUuC-oAAAAJ&hl=en
For formal applications, please submit an online application before the stated deadline. Applications should include a statement of purpose (motivation letter), a CV, transcripts, and two referee details.
- Martín-Durán JM, Pang K, Børve A, Semmler-Lê H, Furu A, Cannon JT, Jondelius U, Hejnol A. 2018. Convergent evolution of bilaterian nerve cords. Nature 553:45-50.
- Martín-Durán JM, Passamaneck YJ, Martindale MQ, Hejnol A. 2016. The developmental basis for the recurrent evolution of deuterostomy and protostomy. Nat Ecol Evol 1:0005