Identification of stage-specific proteins synthesized by rat seminiferous tubules

Journal Article · Mon Aug 01 04:00:00 EDT 1983 · Biol. Reprod.; (United States)

DOI:https://doi.org/10.1095/biolreprod29.1.257· OSTI ID:6671965

Wright, W W; Parvinen, M; Musto, N A; Gunsalus, G L; Phillips, D M; Mather, J P; Bardin, C W

Experiments were conducted to determine how the cycle of the seminiferous epithelium influenced synthesis and secretion of proteins by seminiferous tubules. Tubular segments were treated with collagenase and then cultured with (35S)methionine. These myoid cell-depleted tubules isolated from different stages of the epithelial cycle exhibited, at Stages VI and XII, two distinct peaks of secretion of total radiolabeled proteins. Two-dimensional gel electrophoresis indicated that the patterns of secreted proteins from these two stages were remarkably different, while those from other stages were intermediate between those at the peaks. At least 15 proteins were secreted cyclically. One product, designated Cyclic Protein-2 (CP-2), exhibited a pronounced cycle of secretion, its peak at Stage VI being 30-fold greater than at its nadir at Stages XII-XIV. Further investigation indicated that CP-2 did not appear to originate from myoid cells or dispersed germ cells but could be recovered from Sertoli cell-enriched cultures prepared from Stage VI tubules. Protein secretion by tubular segments was also characterized by immunoprecipitation with two polyspecific antisera directed against Sertoli cell products. Five secretory proteins were identified which had cycles different from one another and from CP-2. In contrast to secreted products, the synthesis of most cellular proteins by tubular segments remained relatively constant throughout the cycle. It is concluded: 1) segments of the seminiferous epithelium secrete proteins into the culture medium which are distinct from cellular proteins; 2) the synthesis of many of these proteins varies with the epithelial cycle; and 3) several of the secreted proteins are of Sertoli cell origin, including a newly identified protein, CP-2.

• OSTI ID: 6671965
• Journal Information: Biol. Reprod.; (United States), Journal Name: Biol. Reprod.; (United States) Vol. 29:1; ISSN BIREB
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
ANIMAL TISSUES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOCHEMISTRY
BIOSYNTHESIS
BODY
CARBOXYLIC ACIDS
CHEMISTRY
DAYS LIVING RADIOISOTOPES
DRUGS
EPITHELIUM
EVEN-ODD NUCLEI
GONADS
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LIGHT NUCLEI
LIPOTROPIC FACTORS
MALE GENITALS
MAMMALS
METABOLISM
METHIONINE
MORPHOLOGY
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANS
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RODENTS
SECRETION
SULFUR 35
SULFUR ISOTOPES
SYNTHESIS
TESTES
TISSUE CULTURES
TISSUES
TRACER TECHNIQUES
VERTEBRATES