Characterization of bursal anti-steroidogenic peptide (BASP) and related proteins from the bursa of fabricius /
Our laboratory has previously partially purified and characterized extracts of the chicken bursa of Fabricius which are potent and efficacious for inhibition of steroid hormone biosynthesis in vitro. The bioactive component, coined Bursal Anti-Steroidogenic Peptide (BASP), has previously been shown...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
2000.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=727847451&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Our laboratory has previously partially purified and characterized extracts of the chicken bursa of Fabricius which are potent and efficacious for inhibition of steroid hormone biosynthesis in vitro. The bioactive component, coined Bursal Anti-Steroidogenic Peptide (BASP), has previously been shown to inhibit steroid hormone biosynthesis from chicken ovarian granulosa cells, adrenal cortical cells from chickens, dogs, and pigs, and from canine primary adrenocarcinoma cells, in vitro. Presently, I evaluated the effect of central administration of BASP on circulating levels of LH in immature chickens. No effect of the selected doses of BASP was measured at the times selected for measurement in these experiments. Attempts to evaluate antiserum produced by immunization with BASP for immunoneutralization of bioactivity on neonatal B-lymphocyte proliferation were hindered by the observation that serum or IgG from rabbits or chickens produced biological effects similar to those produced by BASP. Further investigation of this phenomenon indicated that purified Fab or Fc regions of the IgG molecule were also bioactive, suggesting a bioactive domain in the shared heavy chain immunoglobulin of these regions. A single monoclonal antibody produced by immunization against partially purified BASP recognized a cell type at the cortico-medullary border believed to be consistent in appearance to endocrine or paracrine cells. The recognized protein was demonstrated to be ovoinhibitor or a related protein, with a possible function for inhibition of proteases, and did not have bioactivity consistent with BASP. A polyclonal antiserum produced by immunization of a rabbit with highly purified BASP was used to screen a bursal cDNA expression library created in these studies. Purified and sequenced phagemids from recognized clones resulted in 4 independent nucleotide sequences. Two phagemid nucleotide sequences matched chicken histone H1 with 99% homology. Conventional amino acid sequencing attempts produced 2 sequences also homologous to chicken histone H1. While the identity of BASP was not proven in the present study, recent published evidence suggests that histone H1 may have biological regulatory functions distinct from its more accepted role in DNA supercoiling. The identity of BASP, however, remains in question at the conclusion of the present study. |
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| Item Description: | Vita. "Major Subject: Veterinary Microbiology". |
| Physical Description: | xv, 152 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 131-150). |