biostudies-literatureZhao CResearch Services and Knowledge Transfer Office, University of MacauThe Macau Fund for Development of Science and TechnologyUniversity of MacauUniversidade de Macaue1010523https://www.ebi.ac.uk/biostudies/studies/S-EPMC9754609biostudies-literatureUnknown18(12)Activin and inhibin are both dimeric proteins sharing the same β subunits that belong to the TGF-β superfamily. They are well known for stimulating and inhibiting pituitary FSH secretion, respectively, in mammals. In addition, activin also acts as a mesoderm-inducing factor in frogs. However, their functions in development and reproduction of other species are poorly defined. In this study, we disrupted all three activin/inhibin β subunits (βAa, inhbaa; βAb, inhbab; and βB, inhbb) in zebrafish using CRISPR/Cas9. The loss of βAa/b but not βB led to a high mortality rate in the post-hatching stage. Surprisingly, the expression of fshb but not lhb in the pituitary increased in the female βA mutant together with aromatase (cyp19a1a) in the ovary. The single mutant of βAa/b showed normal follicPLoS geneticsGenetic analysis of activin/inhibin β subunits in zebrafish development and reproduction.PMC9754609MYRG2020-00192-FHSFDCT0132/2019/A3CPG2020-00005-FHSFDCT173/2017/A3MYRG2019-00123-FHSWu KGeng RZhao CZhai YGe WAi NSong WfalseGenetic analysis of activin/inhibin β subunits in zebrafish development and reproduction.Activin and inhibin are both dimeric proteins sharing the same β subunits that belong to the TGF-β superfamily. They are well known for stimulating and inhibiting pituitary FSH secretion, respectively, in mammals. In addition, activin also acts as a mesoderm-inducing factor in frogs. However, their functions in development and reproduction of other species are poorly defined. In this study, we disrupted all three activin/inhibin β subunits (βAa, inhbaa; βAb, inhbab; and βB, inhbb) in zebrafish using CRISPR/Cas9. The loss of βAa/b but not βB led to a high mortality rate in the post-hatching stage. Surprisingly, the expression of fshb but not lhb in the pituitary increased in the female βA mutant together with aromatase (cyp19a1a) in the ovary. The single mutant of βAa/b showed normal follic2022-01-01T00:00:00Z2022 Dec2025-04-04T19:11:30.596Z2025-04-04T19:11:30.596ZS-EPMC97546093646952610.1371/journal.pgen.1010523