Mutation in bone morphogenetic protein receptor-IB is associated with increased ovulation rate in Booroola Mérino ewes.
Ewes from the Booroola strain of Australian Mérino sheep are characterized by high ovulation rate and litter size. This phenotype is due to the action of the FecB(B) allele of a major gene named FecB, as determined by statistical analysis of phenotypic data. By genetic analysis of 31 informative half-sib families from heterozygous sires, we showed that the FecB locus is situated in the region of ovine chromosome 6 corresponding to the human chromosome 4q22-23 that contains the bone morphogenetic protein receptor IB (BMPR-IB) gene encoding a member of the transforming growth factor-beta (TGF-beta) receptor family. A nonconservative substitution (Q249R) in the BMPR-IB coding sequence was found to be associated fully with the hyperprolificacy phenotype of Booroola ewes. In vitro, ovarian granulosa cells from FecB(B)/FecB(B) ewes were less responsive than granulosa cells from FecB(+)/FecB(+) ewes to the inhibitory effect on steroidogenesis of GDF-5 and BMP-4, natural ligands of BMPR-IB. It is suggested that in FecB(B)/FecB(B) ewes, BMPR-IB would be inactivated partially, leading to an advanced differentiation of granulosa cells and an advanced maturation of ovulatory follicles.
Mulsant
P
P
Institut National de la Recherche Agronomique, Laboratoire de Génétique Cellulaire, BP, 27, 31326 Castanet-Tolosan, France. mulsant@toulouse.inra.fr
Lecerf
F
F
Fabre
S
S
Schibler
L
L
Monget
P
P
Lanneluc
I
I
Pisselet
C
C
Riquet
J
J
Monniaux
D
D
Callebaut
I
I
Cribiu
E
E
Thimonier
J
J
Teyssier
J
J
Bodin
L
L
Cognié
Y
Y
Chitour
N
N
Elsen
J M
JM
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics; D000818:Animals; D001315:Australia; D001483:Base Sequence; D055415:Bone Morphogenetic Protein 4; D052004:Bone Morphogenetic Protein Receptors; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics; D005260:Female; D005298:Fertility / Q000235:genetics; D006107:Granulosa Cells / Q000187:drug effects / Q000378:metabolism; D055428:Growth Differentiation Factor 5; D006133:Growth Substances / Q000494:pharmacology; D006579:Heterozygote; D006801:Humans; D008098:Litter Size / Q000235:genetics; D008297:Male; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D010060:Ovulation / Q000235:genetics*; D010641:Phenotype; D020161:Physical Chromosome Mapping; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D017978:Receptors, Growth Factor; D016415:Sequence Alignment; D012756:Sheep / Q000235:genetics* / Q000502:physiology*
C525809:BMP4 protein, human; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; C525893:GDF5 protein, human; D055428:Growth Differentiation Factor 5; D006133:Growth Substances; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D017978:Receptors, Growth Factor; D052004:Bone Morphogenetic Protein Receptors