Rete Testis Fluid (RTF) Proteins: Purification and Characterization of RTF Albumin1

Abstract

A major 68-kDa protein in ram rete testis fluid (RTF) is shown to be chemically and immunologically indistinguishable from albumin in ovine serum. Data obtained with two-dimensional gel electrophoresis of RTF demonstrate the presence of additional proteins with a molecular mass of 68 kDa that do not react with antisera against sheep serum albumin. Biochemical characteristics of albumin preparations isolated by immunoaffinity chromatography from ovine serum and from RTF were compared. Albumin from both sources had the same apparent molecular mass of 68 kDa, the same isoelectric point of approximately 4.2, and neither bound specifically to Concanavalin A. Analysis of tryptic peptide maps, obtained with reverse-phase high-pressure liquid chromatography, indicated no significant differences between digests of the two purified albumin preparations. Results indicate that RTF albumin and serum albumin are the same protein, which implies that RTF albumin may originate from serum. Albumin levels in RTF, collected from different rams and measured by radioimmunoassay, varied between 46 and 164 micrograms/ml, constituting between 11 and 17% of total RTF protein, while albumin levels in sheep plasma were 40,000 micrograms/ml. The protein composition of RTF is discussed in relation to the relative amounts of various components contributed by testis cells and the amounts derived from serum.

Isolation and characterization of transferrin from common carp (Cyprinus carpio L) seminal plasma

“…In the mammalian testis, Tf is synthesized and secreted by Sertoli cells and involved in the net transport of ferric ions to germ cells [38]. It should be emphasized that in mammals 80e90% of rete testis fluid Tf is derived from the testis while only 10e20% from serum [38].…”

“…In the mammalian testis, Tf is synthesized and secreted by Sertoli cells and involved in the net transport of ferric ions to germ cells [38]. It should be emphasized that in mammals 80e90% of rete testis fluid Tf is derived from the testis while only 10e20% from serum [38]. Under the conditions of immunohistochemical staining, used in this study, the carp seminal plasma Tf was localized in the blood vessels of the testis contrary to a1-antiproteinase which was widespread in the carp testis.…”

ASSOCIAÇÃO ENTRE A PRESENÇA DE UM FATOR DE 38 kDa NO PLASMA SEMINAL E A INIBIÇÃO DA MOTILIDADE ESPERMÁTICA NO JUNDIÁ Rhamdia quelen

“…Similarities among some blood and seminal proteins have been reported in mammals (SKINNER et al, 1987), chicken (THURSTON et al, 1982, and fish (LOIR et al, 1990). Such proteins may have functions related to reproduction, whereas proteins found exclusively in the reproductive tract may have more specific functions (KOTLOWSKA et al, 2005).…”

Postvasectomy Alterations in Protein Synthesis and Secretion in the Rat Caput Epididymidis Are Not Repaired After Vasovasostomy

“…File # 12em tratubular compartments was unlikely. Our interpretation is that this albumin came from upstream in the tract, perhaps from the rete testis that has been hypothesized to be leaky to albumin (Skinner et al, 1987). Whether albumin is a physiologically important constituent of epididymal lumen fluid is unknown.…”