Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q7LGC8 (HSD)
 3,196 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The responsiveness of fetal neonatal rat ovaries to LH was investigated in vitro using three complementary approaches. First, steroid production was assessed after culture. In control media, detectable levels of estrogens (estradiol and estrone) and progesterone were only observed from day 6 postpartum and during the second week of life respectively. In the presence of LH (100 ng/ml) ovaries produced both estrogens and progesterone from day 4 postpartum and the response to LH was enhanced with IBMX supplementation in the medium. Second, 3 beta-HSD activity was measured with either LH or (Bu)2 cAMP (1mM). Irrespective to the time-period studies (Bu)2 cAMP stimulated this enzyme whereas the stimulation with LH occurred only from day 5 postpartum Third, specific hCG binding was assessed and we found that it occurred only on days 7 and 10. However, when fetal ovaries were pretreated for 48 h with (Bu)2 cAMP, a specific hCG binding could be detected and progesterone production was enhanced in response to LH. An effect of the nucleotide via a stimulation of the neuraminidase activity did not seem to be involved. Lastly treatment of 18-day-old fetal ovaries with cholera toxin (10nM) or forskolin (1 microM) was found to stimulate progesterone production and VIP (0.1 to 1 microM) stimulated both the 3-HSD activity and the estradiol production. These data suggest that the absence of steroidogenic response to LH before day 4 postpartum could be explained by the absence of receptors, though the LH transmembrane signal-transduction system is functional in fetal ovaries.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Development of fetal rat ovaries responsiveness to LH during organ culture. 166 41

We have previously shown that chondroitin 6-sulfotransferase (C6ST) catalyzes transfer of sulfate not only to position 6 of GalNAc residue of chondroitin but also to position 6 of Gal residue of keratan sulfate. In this study, we examined the sulfation of sialyl lactosamine oligosaccharides by C6ST. C6ST catalyzed transfer of sulfate to NeuAc alpha 2-3Gal beta 1-4GlcNAc (SLN), NeuAc alpha 2-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4GlcNAc (SL1L1), NeuAc alpha 2-3Gal beta 1-4(6-sulfo)GlcNAc beta 1-3(6-sulfo)Gal beta 1-4(6-sulfo)GlcNAc (SL2L4), and their desialylated derivatives, but not to NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc (SLe(x)). The sulfated product formed from SLN was degraded with neuraminidase and reduced with NaBH4. The resulting sulfated disaccharide alditol showed the same retention time in SAX-HPLC as that of [3H]Gal(6SO4) beta 1-4GlcNAc-ol. The sulfated product formed from SLN was also degraded by a reaction sequence of neuraminidase digestion, hydrazinolysis, deamination, and NaBH4 reduction. The final product was coeluted with [3H]Gal(6SO4) beta 1-4anhydromannitol in SAX-HPLC. These observations show that C6ST could transfer sulfate to position 6 of Gal residue of SLN. Incorporation of sulfate into SL2L4 was much higher than the incorporation into SL1L1, suggesting that sulfate moiety attached to adjacent GlcNAc residue may stimulate the transfer of sulfate to Gal residue. The recombinant C6ST also catalyzed sulfation of the sialyl lactosamine oligosaccharides, indicating that a single protein catalyzes sulfation of chondroitin, keratan sulfate, and sialyl lactosamine oligosaccharides. These results raised a possibility that C6ST may be one of the candidates involved in the biosynthesis of sulfated sialyl Lewis x ligand for L-selectin.
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PMID:Sulfation of sialyl lactosamine oligosaccharides by chondroitin 6-sulfotransferase. 914 50