標題: | High Expression Level of Tra2-beta 1 Is Responsible for Increased SMN2 Exon 7 Inclusion in the Testis of SMA Mice |
作者: | Chen, Yu-Chia Chang, Jan-Gowth Jong, Yuh-Jyh Liu, Ting-Yuan Yuo, Chung-Yee 生物科技學系 Department of Biological Science and Technology |
公開日期: | 17-三月-2015 |
摘要: | Spinal muscular atrophy (SMA) is an inherited neuromuscular disease caused by deletion or mutation of SMN1 gene. All SMA patients carry a nearly identical SMN2 gene, which produces low level of SMN protein due to mRNA exon 7 exclusion. Previously, we found that the testis of SMA mice (smn(-/-) SMN2) expresses high level of SMN2 full-length mRNA, indicating a testis-specific mechanism for SMN2 exon 7 inclusion. To elucidate the underlying mechanism, we established primary cultures of testis cells from SMA mice and analyzed them for SMN2 exon 7 splicing. We found that primary testis cells after a 2-hour culture still expressed high level of SMN2 full-length mRNA, but the level decreased after longer cultures. We then compared the protein levels of relevant splicing factors, and found that the level of Tra2-beta 1 also decreased during testis cell culture, correlated with SMN2 full-length mRNA downregulation. In addition, the testis of SMA mice expressed the highest level of Tra2-beta 1 among the many tissues examined. Furthermore, overexpression of Tra2-beta 1, but not ASF/SF2, increased SMN2 minigene exon 7 inclusion in primary testis cells and spinal cord neurons, whereas knockdown of Tra2-beta 1 decreased SMN2 exon 7 inclusion in primary testis cells of SMA mice. Therefore, our results indicate that high expression level of Tra2-beta 1 is responsible for increased SMN2 exon 7 inclusion in the testis of SMA mice. This study also suggests that the expression level of Tra2-beta 1 may be a modifying factor of SMA disease and a potential target for SMA treatment. |
URI: | http://dx.doi.org/10.1371/journal.pone.0120721 http://hdl.handle.net/11536/124503 |
ISSN: | 1932-6203 |
DOI: | 10.1371/journal.pone.0120721 |
期刊: | PLOS ONE |
Volume: | 10 |
Issue: | 3 |
起始頁: | 0 |
結束頁: | 0 |
顯示於類別: | 期刊論文 |