Kawata A, Kato S, Shimizu T, Hayashi H, Hirai S, Misawa H, Takahashi R
Department of Neurology, Tokyo Metropolitan Neurological Hospital, Japan.
Neuroreport. 2000 Aug 21;11(12):2649-53. doi: 10.1097/00001756-200008210-00009.
Two abnormal SOD1 mRNAs, exon 2-skipping and exon 2 and 3-skipping species, were identified from occipital brain tissue of sporadic amyotrophic lateral sclerosis (ALS) patients carrying no mutations in the SOD1 gene. Both transcripts were ubiquitously expressed in non-neuronal as well as neuronal tissues from a subject without neurological diseases. The expression pattern did not show disease specificity or lesional selectivity associated with ALS. Transient expression studies revealed weak expression of the proteins derived from the exon 2-skipping SOD1 cDNA in a cell-free translation system but not in cells. The putative abnormal SOD1 protein may accumulate and exert toxic effects on motor neurons in ALS when the proteolytic system is disturbed by aging or some causal factors.
在超氧化物歧化酶1（SOD1）基因无突变的散发性肌萎缩侧索硬化症（ALS）患者的枕叶脑组织中，鉴定出两种异常的SOD1信使核糖核酸（mRNA），即外显子2跳跃型和外显子2与3跳跃型。在一名无神经系统疾病受试者的非神经组织以及神经组织中，这两种转录本均普遍表达。这种表达模式未显示出与ALS相关的疾病特异性或损伤选择性。瞬时表达研究表明，源自外显子2跳跃型SOD1互补DNA（cDNA）的蛋白质在无细胞翻译系统中表达较弱，但在细胞中不表达。当蛋白水解系统因衰老或某些致病因素而受到干扰时，推测的异常SOD1蛋白可能会积聚并对ALS患者的运动神经元产生毒性作用。
