We wish to continue our chromatin studies on active, potentially active, and inactive mammalian genes by addressing the following four major aims: 1. Ribosomal Chromatin We wish: (a) To determine the distribution of non-nucleosomal and nucleosomal ribosomal chromatin in human-mouse somatic cell hybrids in which the expression of either human or mouse rRNA genes is allelically excluded; (b) To determine the distribution of non-nucleosomal and nucleosomal ribosomal chromatin during the course of rRNA gene activation in regenerating liver; and (c) To elucidate the molecular structure of non-nucleosomal ribosomal chromatin. These studies will employ nucleic acid hybridization, recombinant DNA technology, and specific murine biological systems. 2. Immunoglobulin Chromatin (The Kappa light chain gene) We wish: (a) To identify the proteins that are associated with active nucleosomes; (b) To elucidate the biochemistry of the putative association of active chromatin with the nuclear matrix; (c) To assess the role of an enhancer element in determining the active chromatin phenotype; (d) To define the biochemical basis of a chromatin boundary; and (e) To determine the role of cell differentiation and/or gene rearrangement on these parameters. These studies will employ nucleic acid hybridization, recombinant DNA technology, DNA mediated gene transfer, and specific murine cell lines. 3. Metallothionein-I Chromatin We wish to determine the chromatin phenotypes of the MT-I gene: (a) in its non-induced, potentially active state; (b) in its induced, active state; and (c) in its non-expressed, inactive state. These studies will employ nucleic acid hybridization and specific cell lines. 4. Methylation Sites Along Specific Genes We wish to develop techniques to map every 5-methylcytosine residue along any specific gene by employing antibody isolation and nuclease protection procedures, as well as DNA sequencing strategies.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM029935-08
Application #
3277595
Study Section
Molecular Cytology Study Section (CTY)
Project Start
1982-02-01
Project End
1990-01-31
Budget Start
1989-02-01
Budget End
1990-01-31
Support Year
8
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Texas Sw Medical Center Dallas
Department
Type
Overall Medical
DUNS #
City
Dallas
State
TX
Country
United States
Zip Code
75390
Xiang, Yougui; Park, Sung-Kyun; Garrard, William T (2014) A major deletion in the V?-J? intervening region results in hyperelevated transcription of proximal V? genes and a severely restricted repertoire. J Immunol 193:3746-54
Park, Sung-Kyun; Xiang, Yougui; Feng, Xin et al. (2014) Pronounced cohabitation of active immunoglobulin genes from three different chromosomes in transcription factories during maximal antibody synthesis. Genes Dev 28:1159-64
Zhou, Xiaorong; Xiang, Yougui; Ding, Xiaoling et al. (2013) Loss of an Igýý gene enhancer in mature B cells results in rapid gene silencing and partial reversible dedifferentiation. Mol Cell Biol 33:2091-101
Xiang, Yougui; Park, Sung-Kyun; Garrard, William T (2013) Výý gene repertoire and locus contraction are specified by critical DNase I hypersensitive sites within the Výý-Jýý intervening region. J Immunol 190:1819-26
Zhou, Xiaorong; Xiang, Yougui; Ding, Xiaoling et al. (2012) A new hypersensitive site, HS10, and the enhancers, E3' and Ed, differentially regulate Ig? gene expression. J Immunol 188:2722-32
Xiang, Yougui; Zhou, Xiaorong; Hewitt, Susannah L et al. (2011) A multifunctional element in the mouse Ig? locus that specifies repertoire and Ig loci subnuclear location. J Immunol 186:5356-66
Zhou, Xiaorong; Xiang, Yougui; Garrard, William T (2010) The Ig? gene enhancers, E3' and Ed, are essential for triggering transcription. J Immunol 185:7544-52
Liu, Zhe; Ma, Zhenyi; Terada, Lance S et al. (2009) Divergent roles of RelA and c-Rel in establishing chromosomal loops upon activation of the Igkappa gene. J Immunol 183:3819-30
Xiang, Yougui; Garrard, William T (2008) The Downstream Transcriptional Enhancer, Ed, positively regulates mouse Ig kappa gene expression and somatic hypermutation. J Immunol 180:6725-32
Xiao, Fei; Widlak, Piotr; Garrard, William T (2007) Engineered apoptotic nucleases for chromatin research. Nucleic Acids Res 35:e93

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