| First Author | Hirao Y | Year | 1997 |
| Journal | Development | Volume | 124 |
| Issue | 24 | Pages | 5107-13 |
| PubMed ID | 9362468 | Mgi Jnum | J:45464 |
| Mgi Id | MGI:1195464 | Doi | 10.1242/dev.124.24.5107 |
| Citation | Hirao Y, et al. (1997) Analysis of the mechanism(s) of metaphase I arrest in strain LT mouse oocytes: participation of MOS. Development 124(24):5107-13 |
| abstractText | Oocytes of almost all vertebrates become arrested at metaphase II to await fertilization. Arrest is achieved with the participation of a protein complex known as cytostatic factor (CSF) that stabilizes histone H1 kinase activity. MOS and mitogen-activated protein kinase (MAPK) are important components of CSF. Strain LT/Sv mice, and strains related to LT/Sv, produce a high percentage of atypical oocytes that are arrested at metaphase I when normal oocytes have progressed to metaphase II. The potential role of MOS in metaphase I arrest was investigated using strain LT/Sv and LT-related recombinant inbred strains, LTXBO and CX8-4. MOS and MAPK are produced and functional in maturing LT oocytes. Two experimental paradigms were used to reduce or delete MOS in LT oocytes and assess effects on metaphase I arrest. First, sense and antisense Mos oligonucleotides were microinjected into metaphase I-arrested oocytes. Antisense, but not sense, Mos oligonucleotides promoted the activation of metaphase I-arrested oocytes. Second, mice carrying a Mos null mutation were crossed with LT mice, the null mutation was backcrossed three times to LT mice, and Mos(+/-) N3 mice were intercrossed to produce Mos(-/-), Mos(+/-) and Mos(+/+) N3F1 mice. Oocytes of all three Mos genotypes of N3F1 mice sustained meiotic arrest for 17 hours indicating that metaphase I arrest is not initiated by a MOS-dependent mechanism. However, unlike Mos(+/+) and Mos(+/-) CX8-4 N3F1 oocytes, metaphase I arrest of Mos(-/-) CX8-4 N3F1 oocytes was not sustained after 17 hours and became reversed gradually. These results, like the antisense Mos oligonucleotide microinjection experiments, suggest that MOS participates in sustaining metaphase I arrest in LT oocytes. |
