BMPs and BMPRs in chicken ovary and effects of BMP-4 and -7 on granulosa cell proliferation and progesterone production in vitro.
Bone morphogenetic proteins (BMPs) and their receptors (BMPRs) are now known to have important roles in mammalian ovarian folliculogenesis. This study determined the expression of the mRNA encoding for BMPs and their receptors in the chicken ovary and explored possible roles for them. The expression of the mRNA for BMP-2, -4, -6, -7, and BMPR-IA, -IB, and -II was determined and quantified by a semiquantitative RT-PCR. The mRNAs for all the BMPs and receptors determined were present in both the granulosa (G) and theca (T) cells of the F1, F2, and F3 follicles. All BMP mRNAs increased in G cells with follicular development, whereas only BMP-7 mRNA had this trend in the T cells. BMP-2, -4, and -6 mRNAs in T were similar between follicles. BMPR-IA mRNA was similar in F2G and F3G but lower in F1G. BMPR-IB mRNA was similar in G of all follicles, and BMPR-II mRNA increased with development. In the T, each receptor subtype showed equal distribution between follicles. mRNA levels for BMPR-IB and -II were higher in G than in T, suggesting that the G is a major target for BMPs. BMP-4 and -7 stimulated basal, IGF-I-, and gonadotropin-stimulated progesterone production by cultured G cells, with differential responses between cells from the F1 and F3/4. This suggests involvement in follicular differentiation. BMP-4 and -7 reversed the inhibitory effects of transforming growth factor (TGF)-alpha on basal and gonadotropin-stimulated G cell progesterone production, with greater effect in the F1 than in the F3/4. This effect suggests an important role for BMPs interacting with TGF-alpha in modulating the effects of gonadotropins and IGF-I on follicular differentiation. Finally, BMP-7 stimulated G cell proliferation, but BMP-4 inhibited TGF-alpha+ IGF-I- and/or FSH-stimulated G cell proliferation, suggesting a role in the control of follicular growth during development. These effects of BMP-4 and -7 on the G cell function showed relationships with the expression levels of the BMPs and the BMPR-II.
Onagbesan
O M
OM
Laboratory for Physiology and Immunology of Domestic Animals, Catholic University of Leuven, Karsteelpark, Arenberg 30, B-3001 Heverlee, Belgium. Okanlawon.Onagbesan@agr.kuleuven.ac.be
Bruggeman
V
V
Van As
P
P
Tona
K
K
Williams
J
J
Decuypere
E
E
D000818:Animals; D055415:Bone Morphogenetic Protein 4; D055419:Bone Morphogenetic Protein 7; D052004:Bone Morphogenetic Protein Receptors; D019485:Bone Morphogenetic Proteins / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects; D002645:Chickens; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D015870:Gene Expression; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000032:analysis; D006107:Granulosa Cells / Q000737:chemistry / Q000166:cytology* / Q000187:drug effects; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000494:pharmacology; D006080:Ovarian Follicle / Q000737:chemistry; D010053:Ovary / Q000737:chemistry / Q000502:physiology*; D011374:Progesterone / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000032:analysis; D017978:Receptors, Growth Factor / Q000235:genetics / Q000502:physiology*; D013799:Theca Cells / Q000737:chemistry; D014018:Tissue Distribution; D016211:Transforming Growth Factor alpha / Q000494:pharmacology; D016212:Transforming Growth Factor beta
D055415:Bone Morphogenetic Protein 4; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D012333:RNA, Messenger; D017978:Receptors, Growth Factor; D016211:Transforming Growth Factor alpha; D016212:Transforming Growth Factor beta; D011374:Progesterone; D007334:Insulin-Like Growth Factor I; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D052004:Bone Morphogenetic Protein Receptors