Date of Award
1-1-2004
Embargo Period
1-1-2025
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Molecular and Cellular Biology and Pathobiology
College
College of Graduate Studies
First Advisor
Tracy A. Romano
Second Advisor
Robert W. Chapman
Third Advisor
Patricia A. Fair
Fourth Advisor
Lucille L. London
Abstract
The dolphin immune system is not well characterized, unlike the human and mouse immune systems. As a sentinel species of the marine ecosystem, an understanding of the dolphin immune system will not only contribute to conservation and management of the species, but also contribute to an understanding of the status of the marine ecosystem. cDNA sequences encoding IgA and IgG heavy chains and IgM transmembrane segment of the Atlantic bottlenose dolphin, Tursiops truncatus, were obtained using a combination of reserve transcription of mRNA, PCR amplification using degenerate primers, and 3' and VH-FR3 anchored 5' RACE. Analysis of dolphin γ gene sequences indicates the presence of two isotypes, γ1 & γ2 which differ mainly in the hinge region of the molecule. Genomic Southern blot analysis indicates the γ genes are most likely present in single copy. Genomic Southern blot also indicated multiple α-related sequences are present, but cDNA sequence analysis identified only a single expressed α gene sequence. The deduced amino acid sequences of the dolphin immunoglobulins show greatest similarity to α and γ of evolutionarily-related artiodactyl species (pig, sheep, and cow). Comparison of the transmembrane regions of the membrane-bound immunoglobulins with homologous sequences of other species revealed that the dolphin μ transmembrane (μTM) sequence has an unexpected amino acid shift (Serine to Glycine) in the well-conserved CART motif, which is essential for the immunoglobulin-CD79a/b interaction of the B cell receptor. This Ser -> Gly shift may interfere with the interaction between the μTM and the CD79a/b chains and ultimately affect the efficiency of signal transduction and activation of B cells in the primary immune response. The cloning and characterization of dolphin immunoglobulins will be useful in developing immunological reagents for assessment of dolphin health as well as in understanding the dolphin immune system and its evolutionary implications.
Recommended Citation
Gefroh, Holly Ann, "Molecular Characterization of Immunoglobins A, G, and M Heavy Chains in the Atlantic Bottlenose Dolphin, Tursiops truncatus" (2004). MUSC Theses and Dissertations. 998.
https://medica-musc.researchcommons.org/theses/998
Rights
All rights reserved. All rights reserved. Copyright is held by the author.
