Professor of Pharmacology and Comparative Medicine
Ph.D. Physiology, University of Florida
Postdoctoral Pharmacology, Yale University
National/International Activities:
Member of the Editorial Advisory Board of Journal
of Pharmacology and Experimental Therapeutics. Member
of the Biochemical Endocrinology Study Section,
NIH and Panel Member for NCRR, Special Emphasis
Panel on Research Infrastructure. |
The University of South Alabama has the nation's only research resource devoted to understanding the biology of New World primates such as squirrel monkeys and owl monkeys. The program offers a unique opportunity to develop these primates as animal models of human disease processes. Dr. Scammell's research is closely tied to the goals of the resource.
Research in the laboratory has focused on understanding why New World primates have very high circulating levels of some steroid hormones, including cortisol, progesterone, and testosterone. Studies have shown that hormones are elevated to compensate for end-organ insensitivity suggesting defects in the receptor signaling pathways. Dr. Scammell's laboratory has shown that an elevation in the expression of a large molecular weight FK506-binding immunophilin FKBP51 is a major contributor to inefficient receptor signaling, in particular receptor binding. Furthermore, FKBP51 from New World primates is especially potent in this respect.
The evolutionary pressures that led to these biochemical and physiological changes in New World primates are unknown. However, they have offered an "experiment of nature" that can be explored to understand (1) how the expression of FKBP51 is regulated, (2) how within the receptor heterocomplex FKBP51 affects ligand binding, and (3) other functions of FKBP51, independent of its effects on steroid hormone signaling, that may have been the object of evolutionary pressure. Thus, the laboratory utilizes a number of cellular and molecular approaches to gain insight into the role of this protein in both New and Old World primates.
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Reynolds PD, Ruan Y, Smith DF, Scammell JG. Glucocorticoid resistance in the squirrel monkey is associated with overexpression of the immunophilin FKBP51. J Clin Endocrinol Metab 84:663-669 (1999).
Zuo Z, Urban G, Scammell JG, Dean NM, McLean TK, Aragon IV, Honkanen RE. Ser/Thr protein phosphatase type 5 (PP5) is a negative regulator of glucocorticoid receptor-mediated growth arrest. Biochemistry 38:8849-8857 (1999).
Hofmann W, Schubert D, LaBonte J, Munson L, Gibson S, Scammell JG, Ferrigno P, Sodroski J. Species-specific, postentry barriers to primate immunodeficiency virus infection. J Virology 73:10020-10028 (1999).
Scammell JG, Reddy S, Valentine DL, Coker TN, Nikopoloulos SN, Ross RA. Isolation and characterization of the human secretogranin II gene promoter. Brain Research. Mol Brain Research 75:8-15 (2000).
Scammell JG. Steroid resistance in the squirrel monkey: an old subject revisited. ILAR Journal 41:19-25 (2000).
Denny WB, Valentine DL, Reynolds PD, Smith DF, Scammell JG. Squirrel monkey immunophilin FKBP51 is a potent inhibitor of glucocorticoid receptor binding. Endocrinology 141:4107-4113 (2000).
Urban G, Golden T, Aragon IV, Scammell JG, Dean NM, Honkanen RE. Identification of an estrogen-inducible phosphatase (PP5) that converts MCF-7 human breast carcinoma cells into an estrogen-independent phenotype when expressed constitutively. J Biol Chem 276:27638-27646 (2001).
Scammell JG, Wright JL, Tuck-Muller CM. The origin of four squirrel monkey cell lines established by karyotype analysis. Cytogenet Cell Genet 93:263-264 (2001).
Scammell JG, Denny WB, Valentine DL, Smith DF. Overexpression of the FK506-binding immunophilin FKBP51 is the common cause of glucocorticoid resistance in three New World primates. Gen Comp Endocrinol 124:152-165 (2001).
Ross RA, Hein AM, Braca JA 3 rd , Spengler BA, Biedler JL, Scammell JG. Glucocorticoids induce neuroendocrine cell differentiation and increase expression N-myc in N-type human neuroblastoma cells. Oncol Res 13:87-94 (2002).
Scammell JG, Tucker JA, King JA, Moore CM, Wright JL, Tuck-Muller CM. A kidney epithelial cell line from a Bolivian squirrel monkey. In Vitro Cell Devel Biol - Animal 38:258-261 (2002).
Sinars CR, Cheung-Flynn J, Rimerman RA, Scammell JG, Smith DF, Clardy J. Structure of the large FK506-binding protein FKBP51, an Hsp90-binding protein and a component of steroid receptor complexes. Proc Natl Acad Sci USA 100:868-873 (2003).
Hubler TR, Denny WB, Valentine DL, Cheung-Flynn J, Smith DF, Scammell JG. The FK506-binding immunophilin is transcriptionally regulated by progestin and attenuates progestin responsiveness. Endocrinology 144:2380-2387 (2003).
Scammell JG, Hubler TR, Denny WB, Valentine DL. Organization of the human FK506-binding immunophilin FKBP52 protein gene ( FKBP4 ). Genomics 81:640-643 (2003).
Gross KL, Cioffi EA, Scammell JG. Increased activity of the calcineurin-nuclear factor of activated T cells pathway in squirrel monkey B-lymphoblasts identified by PowerblotT. In Vitro Cell Devel Biol - Animal (in press).
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