A calmodulin binding site in the tuberous sclerosis 2 gene product is essential for regulation of transcription events and is altered by mutations linked to tuberous sclerosis and lymphangioleiomyomatosis
A calmodulin binding site in the tuberous sclerosis 2 gene product is essential for regulation of transcription events and is altered by mutations linked to tuberous sclerosis and lymphangioleiomyomatosis
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DOI：
10.1006/abbi.2001.2682
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发表时间：
2002-02-01
影响因子：
3.9
通讯作者：
Vanaman, TC
中科院分区：
文献类型：
--
作者：
Noonan, DJ;Lou, DY;Vanaman, TC
结节性硬化症2（TSC 2）基因产物中的突变与结节性硬化症（TSC）和性别特异性肺疾病淋巴管平滑肌瘤病（LAM）的病理学有遗传联系。这两种疾病都被归类为细胞迁移、增殖和分化障碍。我们实验室的早期研究（1）将TSC 2与类固醇/核受体信号联系起来。这里提出的研究提供了证据钙调素（CaM）信号在这个TSC 2活动的传播。λ噬菌体人脑cDNA文库的远Western筛选以鉴定TSC 2基因产物（tuberin）的相互作用蛋白，产生了编码人CaM的多个克隆。与P-32标记的块茎蛋白的直接结合证明了Ca 2+依赖性结合CaM-Sepharose，其在C-末端72个残基缺失后丢失。序列（1740）WIARLRHIKRLRQRIC（1755）被鉴定为能够形成碱性两亲性螺旋的序列，该螺旋指示已知钙调素结合蛋白中的CaM结合结构域。与此序列的合成肽的研究表明，非常紧密的钙离子依赖性结合钙调素的色氨酸荧光扰动研究和磷酸二酯酶激活钙调素判断。缺失诱变研究进一步表明，该钙调素结合域是所需的块茎素调节类固醇受体功能，在这一地区的突变可能参与TSC和LAM的病理。(C)2002年，Elsevier Science。
Mutations in the tuberous sclerosis 2 (TSC2) gene product have been genetically linked to the pathology of both tuberous sclerosis (TSC) and the gender-specific lung disease, lymphangioleiomyomatosis (LAM). Both diseases are classified as disorders of cellular migration, proliferation, and differentiation. Earlier studies from our laboratory (1) linked TSC2 with steroid/nuclear receptor signaling. Studies presented here provide evidence for calmodulin (CaM) signaling in the propagation of this TSC2 activity. Far Western screening of a lambda phage human brain cDNA library to identify interacting proteins for the TSC2 gene product (tuberin) yielded multiple clones encoding human CaM. Direct binding with P-32-labeled tuberin demonstrated Ca2+-dependent binding to CaM-Sepharose which was lost upon deletion of the C-terminal 72 residues. The sequence (1740)WIARLRHIKRLRQRIC(1755) was identified as one capable of forming a basic amphipathic helix indicative of CaM binding domains in known calmodulin binding proteins. Studies with a synthetic peptide of this sequence demonstrated very tight Ca2+-dependent binding to CaM as judged by tryptophan fluorescence perturbation studies and phosphodiesterase activation by CaM. Deletion mutagenesis studies further suggested that this CaM binding domain is required for tuberin modulation of steroid receptor function and that mutations in this region may be involved in the pathology of TSC and LAM. (C) 2002 Elsevier Science.