FUNCTION AND REGULATION OF INTERCELLULAR COMMUNICATION

细胞间通讯的功能和调节

• 批准号: 2178959
• 负责人: DAVID L PAUL
• 金额: $ 29.12万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-12-01 至 1998-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2178959
• 关键词: Xenopus; cell cell interaction; disease /disorder model; embryogenesis; fluorescent dye /probe; gap junctions; gene expression; gene mutation; hereditary motor and sensory neuropathy; histogenesis; laboratory mouse; laboratory rabbit; lactation; mammary gland; membrane channels; model design /development; molecular cloning; northern blottings; phosphorylation; protein structure function; protein tyrosine kinase; western blottings

Intercellular communication mediated by gap junctions is believed to underlie crucial cell behaviors such as the spread of electrical excitation in smooth and cardiac muscle. However, gap junctions also selectively connect cells in many non-excitable tissues. In these cases, the biological significance of communication is not clear. A novel method to define the role of communication between nonexcitable cells will be used: We have created connexin mutations that function as dominant- negative inhibitors of communication. These mutants, which do not form active channels, can interact with normal connexins and suppress their ability to form active channels. To analyze the importance of communication in embryogenesis, organ homeostasis/physiology and tumor suppression, we will express inhibiting connexin mutants in early Xenopus development and during rodent mammary gland morphogenesis and lactation. We have discovered that a human hereditary disorder, X-linked Charcot- Marie-Tooth disease (CMTX), is associated with mutations in the gene encoding connexin32. CMTX is a demyelinating peripheral neuropathy. We have shown that Cx32 is abundant in Schwann cells which is consistent with the presentation of this disease. However, it is not known how the CMTX mutations affect Cx32 channel activity, nor how the activity of Cx32, or other connexins that may be present, influence myelination. To investigate these issues, we will use the paired oocyte system to test identified Cx32 mutations for activity. The cellular location of other connexins that may be present in Schwann cells will be determined. An animal model will be developed to permit the early phases of this disease to be studied. Gap junction channels can be gated by pH, Ca++, transjunctional voltage and, as we have recently shown, by phosphorylation. V-src induced tyrosine phosphorylation of Cx43 profoundly inhibits the activity intercellular channels containing it, consistent with a role for communication in transformation by v-src. We propose to test a) if other connexins can be regulated in this fashion b) if kinases other than v-src can exert a similar effect and c) if gating of Cx43 occurs in vivo in the absence of v-src. The latter will be assessed by producing an antibody specific for Cx43 phophorylated at tyrosine-265.

据信，由间隙连接介导的细胞间通信为 基础关键细胞行为，例如电气的传播 光滑和心脏肌肉的激发。但是，差距连接也 有选择地连接许多不可驱行的组织中的细胞。在这些情况下， 交流的生物学意义尚不清楚。一种新颖的方法 定义非电池之间的通信作用将是 二手：我们创建了连接蛋白突变，该突变起主要作用 沟通的负面抑制剂。这些突变体，不形成 主动通道，可以与正常连接素相互作用并抑制其 能够形成活动通道的能力。分析重要性 胚胎发生，器官稳态/生理学和肿瘤中的交流 抑制作用，我们将在早期异爪蟾中表达抑制连接蛋白突变体 发育和啮齿动物乳腺形态发生和泌乳期。 我们发现，人类遗传疾病，X连锁的charcot- 玛丽齿病（CMTX）与基因突变有关 编码connexin32。 CMTX是一种脱髓鞘的周围神经病。我们 已经表明CX32在Schwann细胞中很丰富，这与 这种疾病的介绍。但是，尚不清楚CMTX如何 突变会影响CX32通道活性，也不会影响CX32的活性或如何 可能存在的其他连接蛋白会影响髓鞘。调查 这些问题，我们将使用配对的卵母细胞系统测试确定的CX32 活动突变。其他连接素的细胞位置可能 将确定存在于Schwann细胞中。动物模型将是 开发是为了允许研究这种疾病的早期阶段。 间隙连接通道可以通过pH，CA ++，跨连接电压进行门控 而且，正如我们最近通过磷酸化所示。 V-SRC诱导的酪氨酸 CX43的磷酸化深刻抑制活性间细胞间 包含它的频道，与沟通的角色一致 V-SRC转换。我们建议测试a）其他连接蛋白是否可以 以这种方式调节b）如果除V-SRC以外的其他激酶可以施加 类似的效果和c）如果在没有CX43的门控发生的情况下发生 V-SRC。后者将通过产生特定于特异性的抗体来评估 CX43在酪氨酸-265上进行phophophylylylylylylylylylylylylylylyly。