Exogenous GDF9 but not Activin A, BMP15 or TGFβ alters tight junction protein transcript abundance in zebrafish ovarian follicles.

The tight junction (TJ) complex plays an important role in regulating paracellular permeability and provides mechanical stability in vertebrate epithelia and endothelia. In zebrafish ovarian follicles, TJ complexes in the follicular envelope degenerate as the follicles develop towards maturation. In the current study, transcript abundance of claudins (cldn d, g, h, 1, and 12) and occludins (ocln, and ocln b) were assessed in mid-vitellogenic follicles in response to treatment with exogenous growth factors that are reported to be involved in zebrafish follicle development (i.

Tight junction proteins in zebrafish ovarian follicles: stage specific mRNA abundance and response to 17beta-estradiol, human chorionic gonadotropin, and maturation inducing hormone.

In vertebrate epithelia, the tight junction (TJ) complex plays an important role in the regulation of paracellular permeability and contributes to mechanical stability. Using zebrafish, this study examined the possibility that TJ protein 'machinery' may contribute to the complex process of ovarian follicle development in fishes and be responsive to key endocrine factors that assist in the regulation of this event. Transcript encoding for 18 zebrafish claudin (cldn) and 2 occludin (ocln) orthologs were widely distributed in zebrafish tissues.

Spatial and salinity-induced alterations in claudin-3 isoform mRNA along the gastrointestinal tract of the pufferfish Tetraodon nigroviridis.

In fishes, variation in paracellular permeability is important for regulating salt and water balance. Paracellular permeability is maintained by TJs in vertebrate epithelia. This study examined the spatial distribution and effects of salinity on claudin-3 isoform mRNA expression and abundance along the gastrointestinal (GI) tract of the euryhaline puffer fish (Tetraodon nigroviridis) and related these to morphological heterogeneity of the TJ complex.

Inhibition of premature oocyte maturation: a role for bone morphogenetic protein 15 in zebrafish ovarian follicles.

Bone morphogenetic protein-15 (BMP-15) is a member of the TGF-beta superfamily known to regulate ovarian functions in mammals. Recently, we cloned zebrafish BMP-15 (zfBMP-15) cDNA and demonstrated that it may play a role in oocyte maturation. In this study, we further investigated the role of BMP-15 in zebrafish follicular development and oocyte maturation using an antiserum developed for zfBMP-15 and by microinjection of follicles with antisense zfBMP-15 N-morpholino oligonucleotides or an expression construct containing zfBMP-15 cDNA.