Structure & Function of E.histolytica Adherence Lectin

描述（由申请方提供）：变形虫通过 肠上皮细胞引发阿米巴结肠炎， 每年杀死10万人我们假设溶组织内阿米巴 入侵需要肠上皮细胞中毒， 将260 kDa凝集素转移到上皮细胞膜中。我们提出 这是一个3步的过程，包括：（A）初始遵守 上皮细胞GaINAc通过GPI连接的150 kDa寄生虫凝集素;（B） 二次募集到完整膜的宿主-寄生虫界面 260 kDa Ga 1 NAc凝集素;和（C）插入基底外侧上皮细胞 260 kDa凝集素胞质尾的胞质。醉酒 上皮细胞被假设是由整合素基序上的 凝集素胞质尾干扰上皮细胞结合 整合素的细胞外基质。我们将通过4个具体的测试来验证这一点。 目标。具体目标1将完成结构和功能 鉴定了新描述的E.溶组织剂 具体目标2将研究150 kDa和260 kDa凝集素的相互作用 在阿米巴与上皮细胞的相互作用中。第3章测试 寄生虫转移到上皮细胞的机制和后果 260 kDa凝集素。具体目标4将干预粘附/侵入过程 通过使用RNA消除150和/或260 kDa凝集素的功能， 干扰这些研究的成功完成将揭开 阿米巴入侵和杀害人类，并承诺提供有效的， 合理防治阿米巴病。

DESCRIPTION (provided by the applicant): Invasion of amoebae through the intestinal epithelium initiates amebic colitis, a disease estimated by the WHO to kill 100,000 people annualiy. We hypothesize that Entamoeba histolytica invasion requires intoxication of the epithelial cells lining the intestine by transfer of the 260 kDa lectin into the epithelial cell membrane. We propose that this is a 3 step process consisting of: (A) initial adherence to epithelial cell GaINAc via the GPI-linked 150 kDa parasite lectin; (B) secondary recruitment to the host-parasite interface of the integral membrane 260 kDa Ga1NAc lectin; and (C) insertion into the baso-lateral epithelial cell cytoplasm of the 260 kDa lectin cytoplasmic tail. Intoxication of the epithelial cells is hypothesized to result from the integrin motifs on the lectin cytoplasmic tail interfering with the binding of epithelial cell integrins to the extracellular matrix. We will test this through 4 specific aims. Specific Aim 1 will complete the structural and functional characterization of the newly described 150 kDa lectin of E. histolytica. Specific Aim 2 will study the interaction of the 150 kDa and 260 kDa lectins during amebic interaction with the epithelial cells. Specific Aim 3 will test the mechanism and consequences of parasite transfer to epithelial cells of the 260 kDa lectin. Specific Aim 4 will intervene in the adherence/invasion process by abrogating the functions of the 150 and/or 260 kDa lectins using RNA interference. SUCCESSFUL COMPLETION of these studies will unravel the enigma of amebic invasion and killing of humans, and promises to provide effective and rational approaches to the prevention and treatment of amebiasis.