Comparison of recombinant growth differentiation factor-9 and oocyte regulation of KIT ligand messenger ribonucleic acid expression in mouse ovarian follicles.
Journal - Biology of reproduction (UNITED STATES )
Oocytes secrete factors that regulate the development of the surrounding granulosa cells in ovarian follicles. KIT ligand (KL) mRNA expression in granulosa cells is thought to be regulated by oocytes; however, the factor(s) that mediate this effect are not known. One candidate is the oocyte-specific gene product growth differentiation factor-9 (GDF-9). This study examined the effect of recombinant GDF-9 (rGDF-9) on steady-state KL mRNA expression levels in preantral and mural granulosa cells in vitro. Furthermore, the study compared the effect of rGDF-9 with that of coculture with oocytes at different developmental stages. As determined by RNase protection assay, both KL-1 and KL-2 mRNA levels in preantral and mural granulosa cells were suppressed by 25-250 ng/ml rGDF-9. Fully grown oocytes also suppressed both KL-1 and KL-2 mRNA expression levels. Partly grown oocytes isolated from 7-, 10-, or 12-day-old mice either had no effect on KL mRNA levels or promoted KL-1 mRNA steady-state expression. It is concluded that GDF-9 is likely to mediate the action of fully grown, but not partly grown, oocytes on granulosa cell KL mRNA expression.
|ISSN : ||0006-3363|
|Mesh Heading : ||Animals Bone Morphogenetic Protein 15 Cell Separation Cells, Cultured Female Granulosa Cells Growth Differentiation Factor 9 Growth Substances Mice Mice, Inbred C57BL Nuclease Protection Assays Oocytes Ovarian Follicle Pregnancy RNA, Messenger Recombinant Proteins Stem Cell Factor drug effects metabolism physiology growth & development drug effects physiology genetics pharmacology genetics|
|Mesh Heading Relevant : ||Intercellular Signaling Peptides and Proteins pharmacology physiology metabolism biosynthesis biosynthesis|
Oocyte regulation of kit ligand expression in mouse ovarian follicles.
Journal - Developmental biology (UNITED STATES )
Kit ligand (KL), a product of granulosa cells in ovarian follicles, is a putative regulator of oocyte development. However, the factors that regulate KL mRNA levels in granulosa cells remain unclear. This study tested the hypothesis that oocytes regulate granulosa cell steady-state KL mRNA expression levels and that the characteristics of this regulation are dependent on the stage of growth and development of both oocytes and follicles. Levels of mRNA for the KL splice variants (KL-1 and KL-2) were shown to be high in granulosa cells from preantral follicles and then decline after follicular antrum formation. Preovulatory follicular development was associated with a dramatic increase in steady-state levels of KL-1 mRNA in mural granulosa but not cumulus cells. Regulation of these changes was examined in vitro using partly grown oocytes isolated from preantral follicles and fully grown oocytes isolated from preovulatory follicles. FSH increased the steady-state KL mRNA levels in preantral granulosa cells in vitro. Partly grown oocytes either increased or decreased KL mRNA levels in preantral granulosa cells depending on the absence or presence of FSH stimulation, respectively. Fully grown oocytes reduced the KL mRNA level in preantral granulosa cells and increased the ratio of KL-1 to KL-2 mRNA. In mural granulosa cell culture, FSH augmented testosterone-dependent elevation of the steady-state KL mRNA level, but had no effect alone. Fully grown oocytes reduced KL-2 but not KL-1 mRNA levels in mural granulosa cells treated with testosterone plus FSH, whereas fully grown oocytes reduced levels of both KL transcripts in cumulus cell culture. These effects of oocytes on steady-state KL mRNA expression levels in vitro explain the changes in granulosa cell KL mRNA levels observed during follicle development in vivo. The results therefore support the hypothesis that oocytes regulate granulosa cell kit ligand mRNA levels in a way that is characteristic of the stage of growth and development of the oocyte. Moreover, the results suggest that oocytes play a major role in promoting dynamic changes in gene expression by granulosa cells appropriate to the stage of follicular development.Copyright 1999 Academic Press.
|ISSN : ||0012-1606|
|Mesh Heading : ||Alternative Splicing Animals Cells, Cultured Dose-Response Relationship, Drug Female Follicle Stimulating Hormone Granulosa Cells Mice Mice, Inbred C57BL Oocytes Ovarian Follicle RNA, Messenger Stem Cell Factor Testosterone Time Factors pharmacology metabolism metabolism genetics pharmacology|
|Mesh Heading Relevant : ||Gene Expression Regulation, Developmental metabolism embryology metabolism|