Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Levels of glucose-6-phosphate cyclase (myoinsitol-1-phosphate synthase, EC 5.5.1.4) and myoinositol-1-phosphate phosphatase (myoinositol-1-phosphatase, EC 3.1.3.25) were determined in extracts of testes from10-, 20-, and 30-day-old rats, and in extracts of Sertoli cells, germinal cells, and epididymides. The specific activity of the cyclase was approximately 1/10th that of the phosphatase in all extracts found to contain either enzyme. Among cells in the testis examined, Sertoli cells had highest levels of enzymes required for inositol biosynthesis from glucose, while spermatocytes and round spermatids did not have detectable activity. Spermatozoa from the epididymis also had no detectable cyclase or phosphatase activity. In contrast, extracts of washed epididymides contained exceedingly high specific activities of these enzymes. Primary cultures of Sertoli cells, maintained in a chemically defined medium without added inositol, released inositol into the medium during three successive 24-h periods. The amounts released were greater in cells stimulated by dibutyryl cyclic AMP. Results were interpreted to indicate that inositol in the fluid of seminiferous tubules most probably originates from Sertoli cells, which synthesize inositol from glucose. Additional inositol in the fluid of epididymal tubules could readily be provided by metabolism of glucose by epididymal epithelial cells
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PMID:Myoinositol biosynthesis by Sertoli cells, and levels of myoinositol biosynthetic enzymes in testis and epididymis. 22 90

Studies of six 8-9-month-old rams showed that the specific activities of myoinositol-1-phosphate synthase (EC 5.5.1.4) were highest in epididymal spermatozoa, intermediate in testis and lowest in epididymal tissue. The activity per spermatozoon decreased from caput to cauda. The levels of activity of myo-inositol-1-phosphate synthase in ejaculated spermatozoa from four 3-year-old rams and the seminal vesicles of two 3-year-old rams were insignificant, but in pooled Sertoli cells from the testes of young lambs, the specific activity was much lower than in epididymal spermatozoa although activity per cell was of the same order of magnitude. We conclude that epididymal spermatozoa contain a significant, if not the major, amount of myo-inositol-1-phosphate synthase activity of the epididymis.
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PMID:Activity of myo-inositol-1-phosphate synthase in the epididymal spermatozoa of rams. 688 36