Aim: To study the influence of Ureaplasma urealyticum (Uu) infection on the sperm egg binding associated molecule, sulfoga-lactosylglycerolipid (SGG). Methods: Epididymal sperm was collected from adult mice. The sperm...Aim: To study the influence of Ureaplasma urealyticum (Uu) infection on the sperm egg binding associated molecule, sulfoga-lactosylglycerolipid (SGG). Methods: Epididymal sperm was collected from adult mice. The sperm suspension was randomly divided into 4 groups: the Uu group (coincubated with Uu suspension), the medium group (coincubated with Uu medium), the normal group and the PRS group. Indirect immunofluorescence technique was used to localize SGG on the sperm membrane and to observe the influence of Uu on SGG. Results: In the epididymal sperm, SGG was localized at the head plasma membrane overlying the acroso-mal region. The SGG positive rate of the sperm coincubated with Uu medium was 82.0 %, while the SGG positive rate of those coincubated with Uu suspension was reduced to 39.0 % (P = 0.001). Conclusion: Uu can adhere to the sperm surface. SGG might be a membrane receptor on the sperm surface for Uu infection of the mammalian male genital tract. The blockage of SGG by Uu might be one of the molecular mechanisms correlated with male infertility induced by Uu infection.展开更多
It was thought that cytoplasmic male sterility (CMS), exhibiting maternal inheritance, was associated with cytoplasmic genomes, especially mitochondrial genome because of mitochondrion as the center for energy metabol...It was thought that cytoplasmic male sterility (CMS), exhibiting maternal inheritance, was associated with cytoplasmic genomes, especially mitochondrial genome because of mitochondrion as the center for energy metabolism in eukaryotic cells. Up to now, most of the results demonstrate that pollen abortion in CMS lines is accompanied by expression of novel open reading frames (ORFs) encoding in mitochondrial DNA (mtDNA), which result in the dysfunction of the cells. However, why the cell dysfunction is not taken place in oogamete or somatic cells? Furthermore, because many process, such as the gene transcription, transcript processing, translation and post-translation, and protein importing, folding and assembly, in mtDNA are controlled by nuclear genome, what role does the nuclear genome play in CMS line? Some evidence, e.g. HSP70 and cms-9E, indicate the differences in nuclear genes between CMS line and its maintainer although they are thought to be isonuclear lines. This paper presents an assumption that the sperm nucleus can be modified by ovum cytoplasm in the fertilized egg cell of CMS line during or after fertilization. The modifications include methylation pattern, 5mCpG, and sequences of nuclear DNA, e.g. insertion, deletion, transition and transversion of bases, and control the gene expression, processing and protein folding etc during subsequent events in ontogenesis. The modifications involve in identification of special site in the nuclear genome that is different between CMS line and restorer line, so the latter is not modified. Or the nuclear DNA of restorer is also modified same as CMS line, but other differences in DNA sequence could alter the development during microsporogenesis because the methylation pattern is altered during development. Fig 2, Ref展开更多
文摘Aim: To study the influence of Ureaplasma urealyticum (Uu) infection on the sperm egg binding associated molecule, sulfoga-lactosylglycerolipid (SGG). Methods: Epididymal sperm was collected from adult mice. The sperm suspension was randomly divided into 4 groups: the Uu group (coincubated with Uu suspension), the medium group (coincubated with Uu medium), the normal group and the PRS group. Indirect immunofluorescence technique was used to localize SGG on the sperm membrane and to observe the influence of Uu on SGG. Results: In the epididymal sperm, SGG was localized at the head plasma membrane overlying the acroso-mal region. The SGG positive rate of the sperm coincubated with Uu medium was 82.0 %, while the SGG positive rate of those coincubated with Uu suspension was reduced to 39.0 % (P = 0.001). Conclusion: Uu can adhere to the sperm surface. SGG might be a membrane receptor on the sperm surface for Uu infection of the mammalian male genital tract. The blockage of SGG by Uu might be one of the molecular mechanisms correlated with male infertility induced by Uu infection.
文摘It was thought that cytoplasmic male sterility (CMS), exhibiting maternal inheritance, was associated with cytoplasmic genomes, especially mitochondrial genome because of mitochondrion as the center for energy metabolism in eukaryotic cells. Up to now, most of the results demonstrate that pollen abortion in CMS lines is accompanied by expression of novel open reading frames (ORFs) encoding in mitochondrial DNA (mtDNA), which result in the dysfunction of the cells. However, why the cell dysfunction is not taken place in oogamete or somatic cells? Furthermore, because many process, such as the gene transcription, transcript processing, translation and post-translation, and protein importing, folding and assembly, in mtDNA are controlled by nuclear genome, what role does the nuclear genome play in CMS line? Some evidence, e.g. HSP70 and cms-9E, indicate the differences in nuclear genes between CMS line and its maintainer although they are thought to be isonuclear lines. This paper presents an assumption that the sperm nucleus can be modified by ovum cytoplasm in the fertilized egg cell of CMS line during or after fertilization. The modifications include methylation pattern, 5mCpG, and sequences of nuclear DNA, e.g. insertion, deletion, transition and transversion of bases, and control the gene expression, processing and protein folding etc during subsequent events in ontogenesis. The modifications involve in identification of special site in the nuclear genome that is different between CMS line and restorer line, so the latter is not modified. Or the nuclear DNA of restorer is also modified same as CMS line, but other differences in DNA sequence could alter the development during microsporogenesis because the methylation pattern is altered during development. Fig 2, Ref
