Intraovarian activins are required for female fertility.
Activins have diverse roles in multiple physiological processes including reproduction. Mutations and loss of heterozygosity at the human activin receptor ACVR1B and ACVR2 loci are observed in pituitary, pancreatic, and colorectal cancers. Functional studies support intraovarian roles for activins, although clarifying the in vivo roles has remained elusive due to the perinatal death of activin betaA knockout mice. To study the roles of activins in ovarian growth, differentiation, and cancer, a tissue-specific knockout system was designed to ablate ovarian production of activins. Mice lacking ovarian activin betaA were intercrossed to Inhbb homozygous null mice to produce double activin knockouts. Whereas ovarian betaA knockout females are subfertile, betaB/betaA double mutant females are infertile. Strikingly, the activin betaA and betaB/betaA-deficient ovaries contain increased numbers of functional corpora lutea but do not develop ovarian tumors. Microarray analysis of isolated granulosa cells identifies significant changes in expression for a number of genes with known reproductive roles, including Kitl, Taf4b, and Ghr, as well as loss of expression of the proto-oncogene, Myc. Thus, in contrast to the known tumor suppressor role of activins in some tissues, our data indicate that activin betaA and betaB function redundantly in a growth stimulatory pathway in the mammalian ovary.
Pangas
Stephanie A
SA
Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA.
Jorgez
Carolina J
CJ
Tran
Mai
M
Agno
Julio
J
Li
Xiaohui
X
Brown
Chester W
CW
Kumar
T Rajendra
TR
Matzuk
Martin M
MM
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics; D003338:Corpus Luteum / Q000378:metabolism; D005260:Female; D005298:Fertility / Q000235:genetics*; D015870:Gene Expression; D006107:Granulosa Cells / Q000378:metabolism; D028322:Inhibin-beta Subunits / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D020411:Oligonucleotide Array Sequence Analysis; D010053:Ovary / Q000166:cytology / Q000378:metabolism*; D000090063:Proto-Oncogene Mas; D035381:TATA-Binding Protein Associated Factors / Q000235:genetics; D035362:Transcription Factor TFIID / Q000235:genetics
D002352:Carrier Proteins; C498905:Inhbb protein, mouse; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D035381:TATA-Binding Protein Associated Factors; C491103:Taf4b protein, mouse; D035362:Transcription Factor TFIID; C103008:inhibin beta A subunit; D028322:Inhibin-beta Subunits; C051815:somatotropin-binding protein