PATHOMECHANISM OF NEUROMUSCULAR SYMPTOMS IN MCLEOD SYNDROME

麦克劳德综合征神经肌肉症状的发病机制

• 批准号: 12670612
• 负责人: UEYAMA Hidetsugu
• 金额: $ 1.02万
• 依托单位: OITA MEDICAL UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12670612/
• 关键词: McLeod syndrome; Kx; XK; myopathy; chorea; acanthocyte; immunohistochemistry; Western blot; Kx抗原; 舞糖病

McLeod syndrome is a rare X-linked neuromuscular diseases caused by mutations of KX gene, which produces 37-kDa membrane transport protein. This syndrome manifests acanthocytosis, Hunchington disease-like symptoms characterized by chorea, myopathy such as elevated serum creatine kinase level and proximal muscle weakness and atrophy. However, why these neuromuscular symptoms appear is still unknown. In the present study, we carried out molecular study of our experienced family of McLeod syndrome, and studied the expression of Kx protein and XK mRNA in the muscle and the central nervous system as follows : 1) XK gene analysis : We extracted genomic DNA from the patient and his family members with informed consent. PCR of three exons of XK gene was performed, and directly sequenced. The result revealed the patient had a novel one base (C) insertion mutation at codon 151 of the XK gene and produced 5' frameshift. His mother showed heterozygous for this mutation, whereas his father and olde … More r sister was normal. 2) Production of anti-human Kx peptide antibody : We produced synthetic peptide corresponding to the human Kx amino acid seuqnces as follows : KNGLSEEIEKEVGQAEG. We immunized this peptide to a rabbit and IgG fraction was purified. 3) Expression of KX in human biopsied muscles : We performed immunohistochemistry of the human biopsied muscle specimen by using anti-Kx peptide antibody. In normal muscles, Kx was mainly immunostained in the sarcoplasmic reticulum, but not in the sarcolemma. In McLeod muscle, expression of the sarcoplasmic reticulum seemed to be reduced. 4) Expression of KX in the rat central nervous systems : We performed immunohistochemistry of the rat central nervous system by using this antibody. Kx was expressed ubiquitously in the rat neuron, especially in the nuclear and cytoplasmic lesion (endoplasmic reticulum) but not in the cell membrane. There were no staining for axons or nerve fibers. In RT-PCR analysis of the XK gene, XK mRNA was ubiquitously expressed in the rat brain. Less

McLeod综合征是一种罕见的X连锁神经肌肉疾病，由产生37-kDa膜转运蛋白的KX基因突变引起。该综合征表现为棘红细胞增多症、以舞蹈病为特征的Hunchington病样症状、肌病如血清肌酸激酶水平升高和近端肌无力和萎缩。然而，为什么这些神经肌肉症状出现仍然是未知的。本研究从分子水平对McLeod综合征家系进行了研究，并对Kx蛋白和XK mRNA在肌肉和中枢神经系统中的表达进行了如下研究：1）XK基因分析：在知情同意的情况下，提取患者及其家属的基因组DNA。对XK基因的3个外显子进行PCR扩增，并直接测序。结果发现该患者XK基因第151位密码子发生了一个新的单碱基（C）插入突变，并产生了5'移码。他的母亲表现出这种突变的杂合子，而他的父亲和老人， ...更多信息 我妹妹很正常。2)抗人Kx肽抗体的制备：我们制备了对应于人Kx氨基酸序列的合成肽，如下所示：KNGLSEEIEKEVGQAEG。我们将该肽免疫兔并纯化IgG级分。3)KX在人类活检肌肉中的表达：我们使用抗Kx肽抗体对人类活检肌肉标本进行免疫组织化学。在正常肌肉中，Kx主要在肌浆网中免疫染色，而不是在肌膜中。在McLeod肌中，肌浆网的表达似乎减少。4)KX在大鼠中枢神经系统中的表达：我们使用该抗体对大鼠中枢神经系统进行免疫组织化学。Kx在大鼠神经元中广泛表达，尤其是在细胞核和胞质病变（内质网）中，但不在细胞膜中。轴突或神经纤维无染色。在RT-PCR分析的XK基因，XK mRNA在大鼠脑内普遍表达。少

项目成果

上山秀嗣: "A novel mutation of the McLeod syndrome gene in a Japanese family"Journal of the Neurological Sciences. 176. 151-154 (2000)

Hidetsugu Ueyama：“日本家族中麦克劳德综合征基因的新突变”《神经科学杂志》176. 151-154 (2000)。