National University of Ireland Galway
Paul McEvilly [email:- email@example.com]
Protein adhesion in pedunculate barnacles
Dr Anne Marie Power
This project will study the bioadhesive structures of stalked barnacles and the glues produced by these structures. Previous studies on pedunculate barnacles have to date not focused on the adhesive properties of barnacle cement and work in this area could offer some advantages due to the pelagic habitats these animals occupy compared with acorn barnacles. Analyses in ultrastructure, histology and immunohistochemistry will be applied to stalked barnacles to identify the detail of the cement gland and its properties. The identification of the proteins comprising the glue/cement of pedunculate barnacles is a significant goal of this study, particularly with reference to Dosima fascicularis, the buoy barnacle. Protein chemistry will also be examined to determine the composition of the glue. Mass spectroscopy, Edman degradation and sequencing will be used for protein chemistry, together with raman spectroscopy. Attempts will be made to cultivate pedunculate barnacles including Dosima fascicularis and Lepas anatifera, as this will provide a source of clean sample material. Successful production of larvae would allow larval glue (which is potentially different from adult glue) and details of the life history stages to be studied in these species.
Overall project aims
This project aims to perform a detailed analyses in ultrastructure, histology and immunohistochemistry to provide a greater understanding of the structures required for biological adhesion in stalked barnacle species. Work will focus on analysing the adhesive protein complex to discover how many proteins are involved in adhesion as well as the identity of those proteins. Stalked barnacles will also be cultured, thereby eliminating expensive and potentially risky field sampling missions. Finally data will be collected on the larval stages of stalked barnacles including (potentially) the glues produced by larval stages.
Molecular evolution, ecology and bioactivity of Keratose sponges.
Dr Grace McCormack, Dr Louise Alcock, Prof Mark Johnson
Dictyo- and dendroceratid sponges have long been targeted as candidates in biodiscovery due to the high incidence of bioactive metabolites.However, these marine sponge species are a group notoriously difficult to classify. Their skeleton lacks siliceous, or calcareous spicules, but is rather made up of a reticulate skeleton containing collagen-based fibres.Due to the existing ambiguities in morphology-based classical systematics and ongoing difficulties in the more recent field of chemo-taxonomy, a focus of this project is on applying molecular methods to investigate phylogenetic relationships if this group of sponges.
Comparing a dictyoceratid sponge species with a representative sponge species of another taxonomic order through a highly parallel 454-based tag sequencing strategy, a comprehensive picture of the in- and epi-floras and faunas and extending to microbial community diversity, can be painted. This may also address possible mechanisms of bioactivity. Screening a variety of extracts of sponges amongst other marine invertebrate and alga species in a series of cancer assays may verify the importance of sponges and/or their symbionts. Further mechanistic studies may investigate the potential for drug-discovery and help explain fundamental strategies, or metabolic pathways.
1. To investigate the phylogeny/molecular systematics of selected dictyoceratid and dendroceratid sponges on a variety of spatial scales
2. To explore the microbial diversity associated with sponges and in particular Dysidea fragilis and Haliclona indistincta through metagenomics
3. To explore the biochemical diversity associated with local sponge species including Dysidea fragilis
Mónica Moniz [email:-firstname.lastname@example.org]
Diversity, species concepts and phylogenetic relationships in some taxonomically difficult groups of marine algae
Prof. Mark Johnson, Dr. Fabio Rindi and Prof. Michael Guiry.
Marine algae represent a diverse and genetically heterogeneous assemblage of organisms. Their long evolutionary history has been characterized by complex patterns of morphological character evolution, which has been source of great complication for the taxonomy of many groups. The seaweed flora of Ireland includes approximately 500 species, some of which belong to taxonomically difficult genera.
Overall project aims
This project follows two main lines of investigation:
1- Characterization of species diversity of macroalgal assemblages epibiontic on sponges of Irish shores. This type of assemblages has been very poorly investigated, especially in the Northern hemisphere.
2- Characterization of species boundaries, phylogenetic relationships and biogeography in two selected algal groups present in Ireland:
a) The order Prasiolales (Trebouxiophyceae, Chlorophyta). This is a group of green algae with simple morphology, which includes marine, freshwater and terrestrial members. The Prasiolales are known to possess several metabolites of biotechnological interest, such as polyols, mycosporine-like aminoacids, anti-freezing proteins and bio-adhesives formed by amyloid fibrils
b) Peyssonnelia (Peyssonneliales, Rhodophyta) is a genus of subtidal red algae widespread in temperate and tropical seas, with about 70 species currently recognized. Despite of its abundant occurrence (especially in the Mediterranean), in Europe this genus has been comparatively understudied and its taxonomy still presents major challenges. An unidentified Peyssonnelia sp. from Fiji has recently been shown to contain novel anticancer compounds.
Katrin Hensel [email:-email@example.com]
Wnt signalling in Hydractinia stem cells
Dr Uri Frank, Prof Mark Johnson
Wnt signaling is involved in many cellular processes throughout development. A role for Wnt in pluripotent stem cells has been reported previously in mice, but the precise role it fulfils is not well understood. Understanding the gene regulatory network that controls pluripotency would be relevant to normal development, regenerative medicine and cancer. Studying the decision making of pluripotent stem cells is rather difficult as these cells are only present for a very short time window during development in most animals. Hydractinia is a new model organism for studying pluripotency and we have established new approaches to utilize it in a way not feasible with other models.
Hydractinia echinata is a colonial marine hydroid, living on the shell of hermit-crabs. Hydractinia has a short life cycle, provides daily access to embryos, is easy to culture and amenable to genetic manipulation and posses a remarkable regenerative ability. Regeneration is mediated by pluripotent stem cells, which are maintained in the animal throughout the life cycle. The animal has been a model organism for developmental biology and comparative immunology for decades.
Overall project aims
1. Investigate which Wnt-ligand is affecting the i-cells in Hydractinia.
2. Explore if this Wnt ligand is specific only for i-cells, or if it is also expressed in other cell types.
3. Carry out functional studies to find out which phenotype can be observed after deregulation of this gene.