| First Author | Nishiyama A | Year | 2004 |
| Journal | Brain Res Mol Brain Res | Volume | 125 |
| Issue | 1-2 | Pages | 1-12 |
| PubMed ID | 15193417 | Mgi Jnum | J:91226 |
| Mgi Id | MGI:3046142 | Doi | 10.1016/j.molbrainres.2004.01.012 |
| Citation | Nishiyama A, et al. (2004) Identification and characterization of epsilon-sarcoglycans in the central nervous system. Brain Res Mol Brain Res 125(1-2):1-12 |
| abstractText | Alpha-, beta-, gamma-, and delta-sarcoglycans (SGs) are transmembrane glycoprotein components of the dystrophin-associated protein (DAP) complex, which is critical for the stability of the striated muscle cell membrane. Epsilon-SG was found as a homologue of alpha-SG, but unlike other SG members, it is ubiquitously expressed in various tissues as well as in striated muscle. Moreover, mutations in the epsilon-SG gene cause myoclonus-dystonia, indicating the importance of epsilon-SG for the function in the central nervous system. To gain insight into the role of epsilon-SG, its expression and subcellular distribution in mouse tissues and especially in the mouse brain were investigated. Analysis by reverse transcription-polymerase chain reaction showed four splice variants of epsilon-SG transcripts in the mouse brain, two of which are major transcript forms. One is a conventional form including exon 8 (epsilon-SG1), and the other is a novel form excluding exon 8 but including a previously unknown exon, 11b (epsilon-SG2). Immunoblot analysis using various mouse tissues indicated a broad expression pattern for epsilon-SG1, but epsilon-SG2 was expressed exclusively in the brain. Therefore, both epsilon-SG isoforms coexist in various regions of the brain. Furthermore, these isoforms were found in neuronal cells using immunohistochemical analysis. Subcellular fractionation of brain homogenates, however, indicated that epsilon-SG1 and epsilon-SG2 are relatively enriched in post- and pre-synaptic membrane fractions, respectively. These results suggest that the two epsilon-SG isoforms might play different roles in synaptic functions of the central nervous system. |
