Ph.D. Research
Sea Urchin Immune System
The SpTransformer gene family
The SpTrf gene family is expressed in response to immune challenge. An in-depth analysis of these genes in the sea urchin genome was conducted to understand the sequence complexities of this family and its genomic structure. A theoretical evolutionary history was created for the SpTrf gene family which suggested that these genes arose from multiple duplications and deletions, ectopic duplication and insertions, indels, and point mutations in the exons, which are consistent with the extant genes and family structure.
Additionally, SpTrf gene sequences have a series of internal repeats in a mosaic pattern that necessitate the insertion of large gaps. This has made sequence alignments computationally difficult. The bioinformatic program, PRANK, was tested for aligning the SpTrf gene family.
Relevant Publications
Barela Hudgell, M.A., Smith, L.C., 2021. Sequence Diversity, Locus Structure, and Evolutionary History of the SpTransformer Genes in the Sea Urchin Genome. Front. Immunol. 12, 744783.
Coelomocytes populations
S. purpuratus possesses seven known distinct populations of coelomocytes in the coelomic fluid which respond in diverse ways to immune stimulation. Methods were developed for evaluating sea urchin coelomocytes both for flow cytometry and for lipofection using a commercial lipofection reagent packaged with a range of molecules. While lipofection of coelomocytes failed, a successful gating strategy for flow cytometry was developed to track changes in coelomocytes over time in response to immune challenges.
Relevant Publications
Barela Hudgell, M.A., Grayfer, L., Smith, L.C., 2022. A flow cytometry based approach to identify distinct coelomocyte subsets of the purple sea urchin, Strongylocentrotus purpuratus. Dev. Comp. Immunol. 130, 104352. doi:10.1016/j.dci.2022.104352
Barela Hudgell, M.A., Grayfer, L., Smith, L.C., 2022. Coelomocyte populations in the sea urchin, Strongylocentrotus purpuratus, undergo dynamic changes in response to immune challenge. Front. Immunol. doi: 10.3389/fimmu.2022.940852
Barela Hudgell, M.A., Smith, L.C., 2022. Lipofection mediated transfection fails for sea urchin coelomocytes. PLoS One 17(5): e0267911. doi: 10.1371/journal.pone.026791
Smith and Buckley Labs attending the North American Comparative Immunology Workshop (NACIW); Banff, Canada