HUMAN HEPATOCYTE GROWTH FACTORS

人类肝细胞生长因子

• 批准号: 6230618
• 负责人: WALLACE LEE MCKEEHAN
• 金额: $ 24.37万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6230618
• 关键词: affinity chromatography; biological signal transduction; cell growth regulation; cell type; complementary DNA; enzyme mechanism; fibroblast growth factor; fibroblasts; gene expression; gene targeting; growth factor receptors; heparan sulfate; hepatocellular carcinoma; hepatocyte growth factor; immunochemistry; laboratory mouse; laboratory rat; liver cells; protein isoforms; protein kinase; protein purification; protein structure function; proteoglycan; receptor expression; recombinant DNA; site directed mutagenesis; tissue /cell culture; tissue mosaicism; transforming growth factors

Understanding the cellular and molecular mechanisms underlying the order and precision of compensatory liver regeneration is essential for understanding and intervention in liver carcinogenesis and toxicology as well as development of strategies for liver cell transplantation and gene therapy. Increasing evidence indicates that response to damage by the normal liver is orchestrated by activation and repression of the activity of multiple cytokines within the liver rather than external hormones. Dysfunction of this ordered process results in progression to malignancy. The FGF family of fourteen ligands, their tyrosine kinase receptors (FGF-R) (four genes, 16 splice variants resulting in greater than 100 isoforms) and their heparan sulfate proteoglycan co- receptors within liver are involved in the transient regulation of growth and function in both parenchymal and non-parenchymal cells and the dysfunction leading to hepatoma. This continuation project will characterize significance of expression of FHF-13 (FGF-13) in liver and hepatomas. FGF and FGFR specific heparan sulfate proteoglycan (HSPG) subunits of the FGFR signal transduction complex will be isolated from liver cells, characterized and cDNA coding for their protein cores will be identified by FGF and FGFR affinity chromatography. The promiscuity (or lack of it) of dimerization and functional interaction between FGFR isotypes will be determined in liver cells by using chimeric constructions of ectodomain with the TFG beta intracellular kinases. Impact of the four FGFR intracellular kinase domains and subdomains on mitogenesis, inhibition of cell growth and phenotype of liver cells will be determined using chimeric constructions of ectodomain and intracellular kinase domains. The role of the variant NH2-terminus of the major liver FGF polypeptide, FGF-1, and its proteolytic modification will be determined. Gene targeting to the liver in mice will be employed to dissect the functional role of FGFR1,2,3,4 and FGF-1, on resting and regenerating liver cell phenotypes as well as effect on development of hepatomas (collaborations with Dr. S. Thorgeirsson and Dr. J. Martin). From the results, the expression of FGFR 1,2,3,4 and their variants will be correlated with time and cell phenotypes in primary liver cell culture to mark rare transitional cell types related to mature hepatocytes and bile ductule cell lineages. A unifying hypothesis is presented on which the project is based in which specific FGFR and co-factor HSPG are associated with the mature phenotypes whereas transitional types are characterized by specific co-expression of FGFR and HSPG isoforms.

了解订单背后的细胞和分子机制 精确的代偿性肝再生对于 对肝癌发生和毒理学的认识和干预 以及肝细胞移植策略的发展， 基因治疗越来越多的证据表明， 正常的肝脏是通过激活和抑制 多种细胞因子在肝脏内而不是外部的活性 荷尔蒙 这个有序过程的功能障碍导致进展 恶性肿瘤 FGF家族的14个配体，它们的酪氨酸 激酶受体（FGF-R）（4个基因，16个剪接变体，导致 大于100种同种型）和它们的硫酸乙酰肝素蛋白聚糖共- 肝脏内的受体参与瞬时调节 实质和非实质细胞的生长和功能， 导致肝癌的功能障碍。 这个延续项目将 表征FHF-13（FGF-13）在肝脏中表达的意义， 肝癌 FGF和FGFR特异性硫酸乙酰肝素蛋白聚糖（HSPG） FGFR信号转导复合物的亚基将从 肝细胞的特征和编码其蛋白核心的cDNA将 通过FGF和FGFR亲和层析鉴定。 滥交 (or缺乏）的二聚化和FGFR之间的功能相互作用 同种型将在肝细胞中通过使用嵌合 用TFG β胞内激酶构建胞外域。 四个FGFR细胞内激酶结构域和亚结构域对细胞生长的影响 有丝分裂、细胞生长抑制和肝细胞表型将 可以使用胞外域的嵌合构建体来确定， 胞内激酶结构域。 NH 2-末端变异体的作用 主要的肝FGF多肽FGF-1及其蛋白水解修饰 将被确定。 基因靶向小鼠肝脏将是 用于剖析FGFR 1、2、3、4和FGF-1的功能作用， 静息和再生肝细胞表型以及对 肝癌的发展（与S. Thorgeirsson和 博士J. Martin）。 从结果来看，FGFR 1、2、3、4和 它们的变体将与时间和细胞表型相关， 原代肝细胞培养标记罕见的移行细胞类型相关 成熟肝细胞和胆管细胞谱系。 一个统一 假设提出了该项目是基于哪些具体 FGFR和辅助因子HSPG与成熟表型相关 而过渡型以特异性共表达为特征 FGFR和HSPG同种型。