Document 0079
 DOCN  M9440079
 TI    Analysis of the transcription factor NF-kappaB: induction, function and
       associating proteins.
 DT    9404
 AU    Jamieson CA; Brandeis Univ.
 SO    Diss Abstr Int [B]; 54(4):1796 1993. Unique Identifier : AIDSLINE
       ICDB/94698033
 AB    My thesis research had two goals. One was to identify physiological
       signals that induce the transcription factor NF-kappaB in pre-B and T
       cells. The second was to understand the biological basis of the paradox
       that NF-kappaB regulated inducible genes, such as IL-2 receptor alpha,
       are not constitutively active in B cells where NF-kappaB is
       constitutively present. In most cells, NF-kappaB exists in the cytoplasm
       in association with its inhibitor, IkappaB. Only in B cells is it
       constitutively present in the nucleus. Artificial inducing agents such
       as phorbol esters were known to induce NF-kappaB translocation to the
       nucleus on non-B cells. We were interested in determining key
       physiological signals that induce NF-kappaB. We showed that NF-kappaB is
       induced via the T cell receptor in T cells activated by antigen. To
       determine whether the inducible NF-kappaB had a physiological role, we
       were interested in finding NF-kappaB regulated genes in non-B cells. We
       identified a functional, NF-kappaB binding sequence, TCR-B, in the
       vicinity of previously identified, T cell-specific DNAaseI
       hypersensitive sites within the T cell receptor beta2 locus. Many
       NF-kappaB-regulated genes are expressed when others are not. We
       investigated the contribution of different kappaB-like DNA sequences to
       NF-kappaB function. The sequences from constitutive genes had a higher
       affinity for B cell NF-kappaB and were transcriptionally more active
       than sites from inducible genes. To study the NF-kappaB protein itself
       and protein interactions in vivo I developed a peptide rabbit antiserum
       to the p50 sub-unit C-terminus. This antibody discriminates between
       p50/p65 and p50/c-rel heterodimers in an electrophoretic mobility shift
       assay (EMSA), indicating a difference in p50 C-terminus accessibility.
       In super-shift EMSA I found that p50 participated in several NF-kappaB
       complexes including TCR induced complexes. Immunoprecipitation from B
       and T cells revealed a novel protein, p28, that co-precipitates with
       nuclear p50. Infection with human T cell leukemia virus type 1 (HTLV-1)
       results in adult T cell leukemia. HTLV-1 can infect a wide variety of
       cell types but transformation is restricted to T cells. HTLV-1 tax does
       not bind DNA itself yet somehow induces NF-kappaB to activate
       transcription. In transient transfection assays HTLV-1 tax
       transactivated NF-kappaB dependent transcription more potently in T
       cells than nonlymphoid cells and therefore could be a factor
       contributing to the disease specificity of HTLV-1. (Full text available
       from University Microfilms International, Ann Arbor, MI, as Order No.
       AAD93-22575)
 DE    B-Lymphocytes/CHEMISTRY  HTLV-I/GENETICS  NF-kappa
       B/*GENETICS/PHYSIOLOGY  Receptors, Antigen, T-Cell/GENETICS  Sequence
       Analysis, DNA  *Signal Transduction  T-Lymphocytes/CHEMISTRY
       Transcription, Genetic/GENETICS  THESIS

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