STRUCTURE/FUNCTION OF CHROMATIN IN B-CELL DEVELOPMENT

B 细胞发育中染色质的结构/功能

基本信息

批准号：
2392204
负责人：
VERONICA C BLASQUEZ
金额：
$ 7.74万
依托单位：
UNIVERSITY OF NOTRE DAME
依托单位国家：
美国
项目类别：
财政年份：
1994
资助国家：
美国
起止时间：
1994-04-01 至 1997-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/2392204
关键词：
B lymphocyte DNA binding protein DNA footprinting animal genetic material tag cell differentiation chemical structure function chromatin cytokine genetic enhancer element genetic transcription immunoglobulin genes laboratory mouse mitogens tissue /cell culture

项目摘要

The B-cell developmental system is a paradigm for understanding the mechanisms that enable an organism to respond to extracellular signals. Resting B-cells respond to antigenic stimuli by secretion of immunoglobulin molecules. One of the hallmarks of this terminal differentiation events is an increase in the expression of immunoglobulin molecules reflected in the increased levels of mRNA. Although a large number of studies have been exerted in elucidating the molecular basis for this alteration in the level of gene expression, we still know very little about the mechanisms involved in this process. Our studies of the mouse kappa immunoglobulin locus has revealed that the structure of chromatin around the 3' enchancer region is remarkably different in antibody-secreting plasma B-cells compared with that of mature B-cells. The DNAse I hypersensitive structure first observed in pro B-cells persists at the mature B-cell stage but undergoes a transformation at some stage between the differentiation of B-cells to plasma cells resulting in the spreading of nuclease susceptible sites upstream and downstream of the initial site. Since similar changes are detected in terminally differentiated plasma cells expressing lamba chains, these results suggest that the alteration in the 3'region is a differentiation- dependent event. These changes in chromatin structure may underlie an important aspect of B-cell end-differentiation an might bear upon kappa gene expression. By a combination of reverse genetic, immunological, cell biological, molecular biological, and biochemical techniques, we hope to identify the molecular basis of these chromatin structural changes. We have the unique opportunity to identify the factors that participate in terminal differentiative events in B-cell development, the external agents that these factors respond to, and their possible mechanism of action on gene expression. Specifically, we wish to address the following specific aims: 1) To determine the effects of extracellular stimuli (mitogens and cytokines) on the chromosomal alterations observed during B-cell maturation. This should lead to the establishment of an in vitro system for studying the mechanisms involved in 3' enhancer induction. 2) To localize the DNA sequences within the 3" enhancer that define the formation of DNAse I hypersensitive sites. 3) To identify the precise nucleotide sequences in contact with protein factors in vivo genomic footprinting. 4) To identify and biochemically characterize the protein factors that bind the DNA sequences identified in specific aim#2.

B 细胞发育系统是理解 B 细胞发育系统的范例使生物体能够响应细胞外信号的机制。静息 B 细胞通过分泌免疫球蛋白分子。该航站楼的标志之一分化事件是免疫球蛋白表达的增加分子反映在 mRNA 水平的增加。虽然大已经进行了大量的研究来阐明其分子基础对于基因表达水平的这种改变，我们仍然非常了解关于这个过程所涉及的机制知之甚少。我们的研究小鼠 kappa 免疫球蛋白位点揭示了 3' 增强子区域周围的染色质在分泌抗体的血浆 B 细胞与成熟 B 细胞的比较。 DNAse I 超敏结构首次在原 B 细胞中观察到持续存在于成熟 B 细胞阶段，但在 B细胞分化为浆细胞之间的某个阶段导致核酸酶敏感位点向上游扩散初始站点的下游。由于检测到类似的变化表达兰巴链的终末分化浆细胞，这些结果表明 3' 区域的改变是一种分化- 相关事件。染色质结构的这些变化可能是 B 细胞终末分化的一个重要方面可能对 kappa 产生影响基因表达。通过反向遗传、免疫学的结合，细胞生物学、分子生物学和生化技术，我们希望确定这些染色质结构的分子基础变化。我们有独特的机会来确定影响因素参与 B 细胞发育的终末分化事件，这些因素响应的外部因素，以及它们可能的对基因表达的作用机制。具体来说，我们希望解决具体目标如下： 1) 确定细胞外刺激（丝裂原和促细胞分裂剂）的影响细胞因子）对 B 细胞过程中观察到的染色体改变的影响成熟。这应该导致体外系统的建立用于研究 3' 增强子诱导所涉及的机制。 2) 定位 3" 增强子内的 DNA 序列，该增强子定义了 DNAse I 超敏感位点的形成。 3) 鉴定与蛋白质接触的精确核苷酸序列体内基因组足迹的因素。 4) 鉴定和生化表征蛋白质因子结合特定目标#2 中确定的 DNA 序列。

项目成果

期刊论文数量（8）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Profiling helper T cell subset gene expression in deer mice.

分析鹿小鼠辅助 T 细胞亚群基因表达。

DOI：
10.1186/1471-2172-7-18
发表时间：
2006
期刊：
BMC immunology
影响因子：
3
作者：
Oko,Lauren;Aduddell-Swope,Bethany;Willis,Derall;Hamor,Robyn;Coons,TeresaA;Hjelle,Brian;Schountz,Tony
通讯作者：
Schountz,Tony

Sin Nombre virus infection in field workers, Colorado, USA.

DOI：
10.3201/eid1602.090735
发表时间：
2010-02
期刊：
Emerging infectious diseases
影响因子：
11.8
作者：
Torres-Perez F;Wilson L;Collinge SK;Harmon H;Ray C;Medina RA;Hjelle B
通讯作者：
Hjelle B

Small molecule inhibitors of hantavirus infection.

DOI：
10.1016/j.bmcl.2010.09.092
发表时间：
2010-12-01
期刊：
BIOORGANIC & MEDICINAL CHEMISTRY LETTERS
影响因子：
2.7
作者：
Hall, Pamela R.;Leitao, Andrei;Ye, Chunyan;Kilpatrick, Kathleen;Hjelle, Brian;Oprea, Tudor I.;Larson, Richard S.
通讯作者：
Larson, Richard S.

A developmentally modulated chromatin structure at the mouse immunoglobulin kappa 3' enhancer.

小鼠免疫球蛋白 kappa 3 增强子处的发育调节染色质结构。