MOLECULAR AND CELL BIOLOGY OF FUNGAL PATHOGENS

真菌病原体的分子和细胞生物学

• 批准号: 3091992
• 负责人: Ward E Bullock
• 金额: $ 50.88万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-01-01 至 1994-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3091992
• 关键词: Fungi; cell biology; communicable disease diagnosis; immunodeficiency; molecular pathology; pathologic process

In this program project we will conduct basic studies on medically important fungi at the molecular and cellular level to: 1) enhance understanding of fungal pathogenesis; 2) develop biochemical markers of infection by fungi; 3) explore human phagocyte surface receptor interactions with ligands of Histoplasma capsulatum (Hc) and the subsequent signaling of intraphagocyte biochemical events; 4) further characterize the gene structure and organization of Pneumocystis carinii which we and others recently demonstrated to be a member of the fungi by small subunit ribosomal RNA comparative analysis. Proj. 1 will produce and characterize nucleic acid probes to analyze the gene(s) and other cognate proteins responsible for encoding a plasma membrane proton ion pump in Hc yeasts that maintains a reasonably constant internal pH and may enhance survival within the acidic milieu of host macrophage phagolysosomes. Proj. 2 will examine the fate of Histoplasma yeasts and microconidia in human monocyte/macrophages and alveolar macrophages. The ligands within yeasts and conidia that are recognized by the LFA-1,CR3,p150,95 receptors of macrophages will be identified and purified. Mechanisms of signal transduction initiated by yeast binding to these receptors will be compared to those induced by binding of C3bi-coated erythrocytes to CR3. Proj. 3 will study the role of elastinolytic proteinase in the virulence of invasive Aspergillus species by isolating and cloning the gene for Aspergillus elastase (AE). Cloned AE gene will be used to produce recombinant AE for use in diagnostic testing and virulence studies; the chromosomal location of the gene will be determined, and AE gene probes will be evaluated for diagnosis by in situ hybridization. Proj. 4 will pursue observations that pathogenic species of Aspergillus and Cryptococcus produce large amounts of the polyol, D-mannitol. Capillary gas-chromatography will be used to determine if this metabolite can be employed as a quantitative, diagnostic marker of invasive infection by these fungi in experimental animals and patients. Proj. 5 will extend our knowledge of the fungal nature of P. carinii by employing cloned DNA fragments to characterize gene structure and organization. Genes encoding ribosomal RNAs and the calmodulin gene will be primary cloning targets. Clones of rRNA genes, chromosome markers and repetitive elements will be used as hybridization probes to examine genomic variation among isolates of P. carinii from rat and human hosts.

在这个项目中，我们将进行医学基础研究， 重要真菌在分子和细胞水平上：1）增强 了解真菌的发病机理; 2）开发生物化学标记物， 真菌感染; 3）探讨人吞噬细胞表面受体 与荚膜组织胞浆菌（Hc）配体的相互作用以及随后的 吞噬细胞内生化事件的信号传导; 4）进一步表征 基因结构和组织，我们和其他人 最近被证明是真菌的一员，由小亚基 核糖体RNA比较分析。 项目。 1将产生并表征 用于分析基因和其它同源蛋白质的核酸探针 负责编码Hc酵母中的质膜质子离子泵 它能维持体内pH值的合理恒定， 在宿主巨噬细胞吞噬溶酶体的酸性环境中。 项目 2将 研究组织胞浆菌酵母和小分生孢子在人体中的命运 单核细胞/巨噬细胞和肺泡巨噬细胞。 酵母中的配体 和分生孢子的LFA-1，CR 3，p150，95受体的识别， 巨噬细胞将被鉴定和纯化。 信号机制 将比较酵母与这些受体结合引发的转导 与由C3 bi包被的红细胞与CR 3结合诱导的那些相比。 项目 3 将研究弹性蛋白分解蛋白酶在 通过分离和克隆曲霉属入侵物种的基因， 曲霉弹性蛋白酶（AE）。 克隆的AE基因将用于生产 用于诊断检测和毒力研究的重组AE; 将确定该基因的染色体定位，并且AE基因探针 将通过原位杂交进行诊断评估。 项目 4将 继续观察曲霉菌和隐球菌的致病菌 产生大量的多元醇D-甘露醇 毛细管 气相色谱法将用于确定该代谢物是否可以 作为侵入性感染的定量诊断标志物， 这些真菌在实验动物和病人身上。 项目 5、将我们的 利用克隆DNA了解卡氏肺孢子虫的真菌性质 片段来表征基因结构和组织。 基因编码 核糖体RNA和钙调蛋白基因将是主要的克隆目标。 rRNA基因、染色体标记和重复元件的克隆将在 用作杂交探针，以检查分离株之间的基因组变异， P.大鼠和人类宿主的卡氏虫。