PUBLICATION
Proteolytically Activated, Recombinant Anti-Mullerian Hormone Inhibits Androgen Secretion, Proliferation, and Differentiation of Spermatogonia in Adult Zebrafish Testis Organ Cultures
- Authors
- Skaar, K.S., Nóbrega, R.H., Magaraki, A., Olsen, L.C., Schulz, R.W., and Male, R.
- ID
- ZDB-PUB-110719-5
- Date
- 2011
- Source
- Endocrinology 152(9): 3527-40 (Journal)
- Registered Authors
- Schulz, Rüdiger W.
- Keywords
- none
- MeSH Terms
-
- Androgens
- Animals
- Anti-Mullerian Hormone/metabolism
- Anti-Mullerian Hormone/pharmacology*
- Cell Proliferation/drug effects*
- Male
- Organ Culture Techniques
- Spermatogenesis/drug effects*
- Spermatogenesis/physiology
- Spermatogonia/drug effects
- Spermatogonia/metabolism*
- Testis/drug effects
- Testis/metabolism*
- Zebrafish
- PubMed
- 21750047 Full text @ Endocrinology
Citation
Skaar, K.S., Nóbrega, R.H., Magaraki, A., Olsen, L.C., Schulz, R.W., and Male, R. (2011) Proteolytically Activated, Recombinant Anti-Mullerian Hormone Inhibits Androgen Secretion, Proliferation, and Differentiation of Spermatogonia in Adult Zebrafish Testis Organ Cultures. Endocrinology. 152(9):3527-40.
Abstract
Anti-Müllerian hormone (Amh) is in mammals known as a TGFβ type of glycoprotein processed to yield a bioactive C-terminal homodimer that directs regression of Müllerian ducts in the male fetus and regulates steroidogenesis and early stages of folliculogenesis. Here, we report on the zebrafish Amh homologue. Zebrafish, as all teleost fish, do not have Müllerian ducts. Antibodies raised against the N- and C-terminal part of Amh were used to study the processing of endogenous and recombinant Amh. The N-terminally directed antibody detected a 27-kDa protein, whereas the C-terminally directed one recognized a 32-kDa protein in testes extracts, both apparently not glycosylated. The C-terminal fragment was present as a monomeric protein, because reducing conditions did not change its apparent molecular mass. Recombinant zebrafish Amh was cleaved with plasmin to N- and C-terminal fragments that after deglycosylation were similar in size to endogenous Amh fragments. Mass spectrometry and N-terminal sequencing revealed a 21-residue N-terminal leader sequence and a plasmin cleavage site after Lys or Arg within Lys-Arg-His at position 263–265, which produce theoretical fragments in accordance with the experimental results. Experiments using adult zebrafish testes tissue cultures showed that plasmin-cleaved, but not uncleaved, Amh inhibited gonadotropin-stimulated androgen production. However, androgens did not modulate amh expression that was, on the other hand, down-regulated by Fsh. Moreover, plasmin-cleaved Amh inhibited androgen-stimulated proliferation as well as differentiation of type A spermatogonia. In conclusion, zebrafish Amh is processed to become bioactive and has independent functions in inhibiting both steroidogenesis and spermatogenesis.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping