Dr. Sen's long term goal is to understand at a molecular level the sequential steps of T-cell differentiation. Dr. Sen proposes that identification of key transcription factors that regulate stage-specific gene expression provides an important mechanism to examine the differentiation process. The regulation of the T-cell receptor beta chain gene and the CD8 alpha chain gene will be studied as probes of gene expression in double negative and double positive stages of T-cell development, respectively.
The Specific Aims of this application are: 1) To study the biological function and regulation of a promoter identified in the J beta 2-C beta 2 intron. It is proposed that this promoter may regulate TCR beta rearrangements, which will be investigated by deleting the promoter in embryonic stem cells. Critical promoter factors will be identified by transfection, mutagenesis and in vitro binding studies. 2) To identify the factors that activate the TCR beta enhancer in double negative T- cells. A core enhancer will be defined and differentiation stage specific factors that interact with these sequences will be identified by comparing extracts from mutant mice and staged fetal thymocytes. 3) To define and characterize CD8 alpha gene regulatory elements. Transgenic mice will be used to identify combinations of DNAase I hypersensitive sites that function as a locus control region and confer developmentally appropriate regulation. The combined genetic and biochemical experiments are expected to identify factors that respond to developmental cues in the thymus and, thereby, provide targets for the manipulation of T- cell differentiation.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
2R01GM043874-06A1
Application #
2182243
Study Section
Special Emphasis Panel (ZRG5-IMS (03))
Project Start
1990-04-01
Project End
2000-03-31
Budget Start
1995-09-30
Budget End
1996-03-31
Support Year
6
Fiscal Year
1995
Total Cost
Indirect Cost
Name
Brandeis University
Department
Type
Organized Research Units
DUNS #
616845814
City
Waltham
State
MA
Country
United States
Zip Code
02454
Carvajal, I M; Sen, R (2000) Functional analysis of the murine TCR beta-chain gene enhancer. J Immunol 164:6332-9
Wang, W; Wykrzykowska, J; Johnson, T et al. (1999) A NF-kappa B/c-myc-dependent survival pathway is targeted by corticosteroids in immature thymocytes. J Immunol 162:314-22
Sen, J; Kapeller, R; Fragoso, R et al. (1996) Intrathymic signals in thymocytes are mediated by p38 mitogen-activated protein kinase. J Immunol 156:4535-8
Sen, J; Venkataraman, L; Shinkai, Y et al. (1995) Expression and induction of nuclear factor-kappa B-related proteins in thymocytes. J Immunol 154:3213-21
Sen, J; Shinkai, Y; Alt, F W et al. (1994) Nuclear factors that mediate intrathymic signals are developmentally regulated. J Exp Med 180:2321-7
Landry, D B; Engel, J D; Sen, R (1993) Functional GATA-3 binding sites within murine CD8 alpha upstream regulatory sequences. J Exp Med 178:941-9
Pierce, J W; Gifford, A M; Baltimore, D (1991) Silencing of the expression of the immunoglobulin kappa gene in non-B cells. Mol Cell Biol 11:1431-7