First Author | Meng X | Year | 2015 |
Journal | J Biol Chem | Volume | 290 |
Issue | 19 | Pages | 11853-64 |
PubMed ID | 25787082 | Mgi Jnum | J:250419 |
Mgi Id | MGI:6102239 | Doi | 10.1074/jbc.M114.627653 |
Citation | Meng X, et al. (2015) Genetic Deficiency of Mtdh Gene in Mice Causes Male Infertility via Impaired Spermatogenesis and Alterations in the Expression of Small Non-coding RNAs. J Biol Chem 290(19):11853-64 |
abstractText | Increased expression of metadherin (MTDH, also known as AEG-1 and 3D3/LYRIC) has been associated with drug resistance, metastasis, and angiogenesis in a variety of cancers. However, the specific mechanisms through which MTDH is involved in these processes remain unclear. To uncover these mechanisms, we generated Mtdh knock-out mice via a targeted disruption of exon 3. Homozygous Mtdh knock-out mice are viable, but males are infertile. The homozygous male mice present with massive loss of spermatozoa as a consequence of meiotic failure. Accumulation of gamma-H2AX in spermatocytes of homozygous Mtdh knock-out mice confirms an increase in unrepaired DNA breaks. We also examined expression of the DNA repair protein Rad18, which is regulated by MTDH at the post-transcriptional level. In testes from Mtdh exon 3-deficient mice, Rad18 foci were increased in the lumina of the seminiferous tubules. The Piwi-interacting RNA (piRNA)-interacting protein Mili was expressed at high levels in testes from Mtdh knock-out mice. Accordingly, genome-wide small RNA deep sequencing demonstrated altered expression of piRNAs in the testes of Mtdh knock-out mice as compared with wild type mice. In addition, we observed significantly reduced expression of microRNAs (miRNAs) including miR-16 and miR-19b, which are known to be significantly reduced in the semen of infertile men. In sum, our observations indicate a crucial role for MTDH in male fertility and the DNA repair mechanisms required for normal spermatogenesis. |