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

mRNA levels of the enzymes involved in taurine synthesis were compared among 12 rat tissues. Using a quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Northern-blotting, high levels of mRNA for cysteine dioxygenase were confirmed in the liver and kidney. Unexpectedly, the mRNA levels in epididymal and perirenal white adipose tissues and interscapular brown adipose tissue were remarkably high, at least compared with those observed in the liver and kidney. Cysteine dioxygenase mRNA levels in other tissues were very low. Using Northern blotting, significant amounts of cysteine sulfinic acid decarboxylase mRNA were detected in the liver, kidney, epididymal and perirenal white adipose tissues, and brown adipose tissue, but not in other tissues. Again, the mRNA levels of cysteine sulfinic acid decarboxylase in adipose tissues were comparable to or even higher than those in the liver and kidney. The activity of cysteine sulfinic acid decarboxylase in white and brown adipose tissues was 50% to 80% of that in the liver and much higher than the values observed in kidney, lung, and brain. However, the occurrence of cysteine dioxygenase activity in adipose tissues was not confirmed.
 ...
PMID:mRNA expression of enzymes involved in taurine biosynthesis in rat adipose tissues. 1220 Jul 66

Sperm entering the epididymis are immotile and cannot respond to stimuli that will enable them to fertilize. The epididymis is a highly complex organ, with multiple histological zones and cell types that together change the composition and functional abilities of sperm through poorly understood mechanisms. Sperm take up taurine during epididymal transit, which may play antioxidant or osmoregulatory roles. Cysteine dioxygenase (CDO) is a critical enzyme for taurine synthesis. A previous study reported that male CDO-/- mice exhibit idiopathic infertility, prompting us to investigate the functions of CDO in male fertility. Immunoblotting and quantitative reverse transcription-polymerase chain reaction analysis of epididymal segments showed that androgen-dependent CDO expression was highest in the caput epididymidis. CDO-/- mouse sperm demonstrated a severe lack of in vitro fertilization ability. Acrosome exocytosis and tyrosine phosphorylation profiles in response to stimuli were normal, suggesting normal functioning of pathways associated with capacitation. CDO-/- sperm had a slight increase in head abnormalities. Taurine and hypotaurine concentrations in CDO-/- sperm decreased in the epididymal intraluminal fluid and sperm cytosol. We found no evidence of antioxidant protection against lipid peroxidation. However, CDO-/- sperm exhibited severe defects in volume regulation, swelling in response to the relatively hypo-osmotic conditions found in the female reproductive tract. Our findings suggest that epididymal CDO plays a key role in post-testicular sperm maturation, enabling sperm to osmoregulate as they transition from the male to the female reproductive tract, and provide new understanding of the compartmentalized functions of the epididymis.
 ...
PMID:Cysteine dioxygenase is essential for mouse sperm osmoadaptation and male fertility. 2960 78