Isoform 1 or the secreted form is a binding and antagonizing protein for members of the TGF-beta family, such us activin, BMP2 and MSTN. Inhibits activin A-, activin B-, BMP2- and MSDT-induced cellular signaling; more effective on activin A than on activin B. Involved in bone formation; inhibits osteoclast differentiationc. Involved in hematopoiesis; involved in differentiation of hemopoietic progenitor cells, increases hematopoietic cell adhesion to fibronectin and seems to contribute to the adhesion of hematopoietic precursor cells to the bone marrow stroma. Isoform 2 or the nuclear form is probably involved in transcriptional regulation via interaction with MLLT10.
Expressed in a wide range of tissues.
Involvement in disease
Note=A chromosomal aberration involving FSTL3 is found in a case of B-cell chronic lymphocytic leukemia. Translocation t(11;19)(q13;p13) with CCDN1.
Secreted and Nucleus. Although alternative initiation has been demonstrated and resulted in different localization, the major source of nuclear FSTL3 appears not to depend on translation initiation at Met-27 according to.
Immunohistochemical analysis of formalin fixed and paraffin embedded Human testis tissue labeling FSTL3 with ab170680 at 1/10 dilution followed by peroxidase conjugation of the secondary antibody and DAB staining.