HUMAN HEPATOCYTE GROWTH FACTORS

人类肝细胞生长因子

• 批准号: 6517084
• 负责人: WALLACE LEE MCKEEHAN
• 金额: $ 25.73万
• 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/6517084
• 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.

了解该顺序的细胞和分子机制 补偿性肝脏再生的精度对于 了解和干预肝癌发生和毒理学 以及制定肝细胞移植策略和 基因疗法。越来越多的证据表明，对损害的反应 正常肝脏通过激活和抑制来精心策划 多种细胞因子在肝内而不是外部的活性 激素。 该有序过程的功能障碍导致进展 发生恶性。 FGF家族十四个配体，他们的酪氨酸 激酶受体（FGF-R）（四个基因，16个剪接变体，导致导致 大于100的同工型）及其硫酸乙酰肝素蛋白聚糖共同 肝脏内的受体参与了 实质和非副质细胞的生长和功能以及 导致肝癌的功能障碍。 这个延续项目将 表征FHF-13（FGF-13）在肝脏中的表达显着性和 肝瘤。 FGF和FGFR特异性硫酸肝素蛋白聚糖（HSPG） FGFR信号转导复合物的亚基将从 肝细胞，表征其蛋白质核心的cDNA将会 通过FGF和FGFR亲和色谱鉴定。 滥交 （或缺乏IT）FGFR之间的二聚化和功能相互作用 同种型将在肝细胞中使用嵌合确定 与TFGββ的细胞内激酶的构造。 四个FGFR细胞内激酶结构域和子域对 有丝分裂发生，抑制细胞生长和肝细胞表型将 使用外生域的嵌合构建和 细胞内激酶结构域。 变体NH2末端的作用 主要的肝FGF多肽FGF-1及其蛋白水解修饰 将确定。 针对小鼠肝脏的基因将是 用于剖析FGFR1,2,3,4和FGF-1的功能作用 静止和再生肝细胞表型以及对 开发肝瘤（与S. Thorgeirsson博士的合作 J. Martin博士）。 从结果中，FGFR的表达1,2,3,4和 它们的变体将与时间和细胞表型相关 原代肝细胞培养以标记罕见的过渡细胞类型相关 成熟的肝细胞和胆管导管细胞谱系。 统一 提出了该项目所基于的假设 FGFR和联合因素HSPG与成熟表型有关 而过渡类型的特征是特定的共表达 FGFR和HSPG同工型。