Molecular Pathogenesis Study Of Charcot-Marie-Tooth 2L Caused By HSP22 Variation

Background:Charcot-Marie-Tooth disease (CMT) is the most common inherited peripheral neuropathy presenting with the phenotype of a chronic progressive neuropathy affecting both the motor and sensory nerves and high morbidity. Electrophysiological studies and pathological basis of clinical electrophysiological or anatomical pathology findings distinguish two major types-the demyelinating form and the axonal form. CMT2L was found to be caused by a novel 423G->T (Lys141Asn) missense mutation of HSP22. The mechanism of the HSP22 variation is still unknown, there are two different theoretical speculation:1) the loss of function mutation,2) acquired the toxic effects. The relatively late onset of the disease, which suggests an accumulative tissue damage pattern, indicates a more indirect, perhaps protective role of the wild-type sHSPs rather than an immediate role in proper tissue function.Objective:To screen differentially expressed proteins in human sural nerve between CMT2L patients and normal controls for understanding the pathogenesis of CMT. Results:Six differential protein spots were identified by PDQUEST analysis. Six proteins were successfully identified by MS, which are Tubulin alpha-1B. Actin cytoplasmic 2,Tubulin alpha-1A,POTE ankyrin domain family member F,Glutathione S-transferase omega-1 and EH domain-containing protein 2. The last two proteins may be of significant implications in axon degeneration, and may have some correction with axon degeneration. They both co-localized with HSP22 in the cell cytoplasm.Conclusions:Glutathione S-transferase omega-1 and EH domain-containing protein 2 may be involved in the occurrence and development of CMT2L and the related mechanisms remain to be elucidated. Two-dimensional electrophoresis and mass spectrometry technique provide an effective technique for screening the differentially expressed proteins in the development and progression of CMT.