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1.
Aryl and steroid sulfatase in the human ovary 总被引:2,自引:0,他引:2
2.
Synthesis and stability of steroid sulfatase in fibroblasts from multiple sulfatase deficiency 总被引:1,自引:0,他引:1
Multiple sulfatase deficiency is a lysosomal storage disorder, which can be divided into group I with severe and group II with moderate deficiencies in sulfatases. Antibodies raised against steroid sulfatase purified from human placenta were used to follow the biosynthesis and stability of this enzyme in multiple sulfatase-deficiency fibroblasts. Fibroblasts from both groups synthesized steroid sulfatase of apparently normal size and stability, while the apparent rate of enzyme synthesis and catalytic properties of steroid sulfatase were affected to a variable extent. Cell lines were observed, that synthesized normal amounts of steroid-sulfatase polypeptides, which were catalytically inactive, as well as cell lines that synthesized diminished amounts of catalytically active steroid sulfatase. 相似文献
3.
The possible role of intrauterine estrogen sulfatase and steroid sulfatase around the time of parturition in the guinea pig was investigated. [3H]Estrone sulfate or [3H]pregnenolone sulfate was incubated with intrauterine tissues. Estrogen sulfatase was found in placenta, endometrium, decidua basalis, amnion and chorion. The presence of steroid sulfatase was established in endometrium and decidua basalis but not in placenta or the fetal membranes. Examination of activities in early (days 32-35), mid (days 44-46) and late (within 5 days of parturition) gestation revealed no significant change in estrogen sulfatase specific activity in decidua basalis. However, in chorion and endometrium this activity was seen to increase approx. 12-fold (P less than 0.001) and 2.8-fold (P less than 0.001), respectively, from early to late gestation. In placenta, estrogen sulfatase activity appeared to increase 2.4-fold (P less than 0.001) and in amnion it decreased 2.8-fold (P less than 0.002). Steroid sulfatase activity in decidua basalis did not change during gestation, while activity in endometrium was found to increase by a factor of 5.3 (P less than 0.001), from early to late gestation. The increases, both in estrogen sulfatase activity in chorion, endometrium and placenta and in steroid sulfatase activity in endometrium, occurred primarily within the final 3 weeks of gestation. In contrast, the decrease in estrogen sulfatase activity in amnion occurred principally between the fifth and sixth weeks of gestation. Analysis of radiolabelled metabolites indicated that estradiol and progesterone could be produced via estrogen sulfatase and steroid sulfatase activities in certain tissues. Subcellular fractionation of tissues revealed that the greatest specific activity and total activity, in all cases, was associated with the 105,000 g pellet. Significant activity was also detected in the 750 and 10,000 g pellets but not in the 105,000 g supernatant. Radioimmunoassay of endogenous estradiol-17 beta (estradiol) in chorion extracts revealed a 6.3-fold increase in the hormone from mid to late gestation. Estradiol levels in endometrium and myometrium did not appear to change during this time. It was concluded that increased estrogen sulfatase activity in guinea pig chorion in late gestation occurs along with elevated levels of the hormone estradiol which may be important for parturition in this species. 相似文献
4.
Regulation of rat testis steroid sulfatase. A kinetic study 总被引:2,自引:0,他引:2
5.
Selcer KW Difrancesca HM Chandra AB Li PK 《The Journal of steroid biochemistry and molecular biology》2007,105(1-5):115-123
Steroid sulfatase (EC 3.1.6.2) is an enzyme that removes the sulfate group from 3β-hydroxysteroid sulfates. This enzyme is best known for its role in estrogen production via the fetal adrenal–placental pathway during pregnancy; however, it also has important functions in other physiological and pathological steroid pathways. The objective of this study was to examine the distribution of steroid sulfatase in normal human tissues and in breast cancers using immunohistochemistry, employing a newly developed steroid sulfatase antibody. A rabbit polyclonal antiserum was generated against a peptide representing a conserved region of the steroid sulfatase protein. In Western blotting experiments using human placental microsomes, this antiserum crossreacted with a 65 kDa protein, the reported size of steroid sulfatase. The antiserum also crossreacted with single protein bands in Western blots of microsomes from two human breast cancer cell lines (MDA-MB-231 and MCF-7) and from rat liver; however, there were some size differences in the immunoreactive bands among tissues. The steroid sulfatase antibody was used in immunohistochemical analyses of individual human tissue slides as well as a human tissue microarray. For single tissues, human placenta and liver showed strong positive staining against the steroid sulfatase antibody. ER+/PR+ breast cancers also showed relatively strong levels of steroid sulfatase immunoreactivity. Normal human breast showed moderate levels of steroid sulfatase immunoreactivity, while ER−/PR− breast cancer showed weak immunoreactivity. This confirms previous reports that steroid sulfatase is higher in hormone-dependent breast cancers. For the tissue microarray, most tissues showed some detectable level of steroid sulfatase immunoreactivity, but there were considerable differences among tissues, with skin, liver and lymph nodes having the highest immunoreactivity and brain tissues having the lowest. These data reveal the utility of immunohistochemistry in evaluation of steroid sulfatase activity among tissues. The newly developed antibody should be useful in studies of both humans and rats. 相似文献
6.
Summary The gene locus for steroid sulfatase, deficiency of which causes X-linked ichthyosis, is assigned to Xp11Xpter by analysis of 24 man-Chinese hamster somatic cell hybrids. High steroid sulfatase,activity in a hybrid clone having retained only part of Xq is explained by demonstration of an additional late-replicating human X chromosome. This observation confirms previous evidence for noninactivation of the STS locus. 相似文献
7.
Kríz L Bicíková M Hampl R 《Physiological research / Academia Scientiarum Bohemoslovaca》2008,57(5):657-668
Steroid sulfatase (EC 3.1.6.2) is an important enzyme involved in steroid hormone metabolism. It catalyzes the hydrolysis of steroid sulfates into their unconjugated forms. This action rapidly changes their physiological and biochemical properties, especially in brain and neural tissue. As a result, any imbalance in steroid sulfatase activity may remarkably influence physiological levels of active steroid hormones with serious consequences. Despite that the structure of the enzyme has been completely resolved there is still not enough information about the regulation of its expression and action in various tissues. In the past few years research into the enzyme properties and regulations has been strongly driven by the discovery of its putative role in the indirect stimulation of the growth of hormone-dependent tumors of the breast and prostate. 相似文献
8.
A proposed role for ZO-1 in targeting connexin 43 gap junctions to the endocytic pathway 总被引:5,自引:0,他引:5
Gap junctions are intercellular channels organized in plaque that directly link adjacent cells. Connexins (Cx), the constitutive proteins of gap junctions are associated with several partner proteins (cytoskeletal, anchoring) which could participate in plaque formation and degradation. Coimmunoprecipitation and indirect immunofluorescence analyses showed that ZO-1, a tight junction-associated protein, was linked to Cx43 in the testis. By using gamma-hexachlorocyclohexane (HCH), known to induce gap junction endocytosis, we demonstrated that endocytosis increased Cx43/ZO-1 association within the cytoplasm of treated Sertoli cells. In control cells, the two proteins were present, as expected, at the plasma membrane level, but poorly colocalized. The increased intracytoplasmic Cx43/ZO-1 complex was associated with a shift towards increased levels of Cx43 P1 and P2 isoforms. The HCH induced Cx43 hyperphosphorylation was abolished by the ERK inhibitor PD98059 suggesting that this effect could be mediated through activation of the ERK pathway. These data strongly support a novel role for ZO-1 in the turnover of Cx43 during gap junction plaque endocytosis. 相似文献
9.
10.
Partial characterization of steroid sulfohydrolase and steroid sulfotransferase activities in purified porcine Leydig cells 总被引:1,自引:0,他引:1
Subcellular fractions of purified pig Leydig cells from 7 different animals have been investigated with respect to their abilities to catalyze the sulfation of several steroids and the hydrolysis of the sulfated forms of these same steroids. Considerable estrone sulfate sulfohydrolase of pH optimum 7.5 and high apparent Km was found to be concentrated in the 105,000 g pellet but no evidence was obtained, in any subcellular fraction, for the presence of any activity toward the 3-sulfate of pregnenolone, dehydroepiandrosterone (DHA) or delta 5-androstene-3 beta,17 beta-diol (androstenediol). Cytosolic sulfotransferase activity toward estrone, pregnenolone, DHA and androstenediol was present in each animal. The activity toward these 4 substrates was eluted from a gel filtration column as a single peak of apparent molecular weight 43 KDa. Upon chromatofocusing, a sharp estrogen sulfotransferase peak of apparent pI 6.1 and pH optimum 9.5, was clearly separated from the neutral steroid sulfotransferase which eluted over a more acidic pH range in a manner suggestive of the presence of several isozymes. This latter, which exhibited a wide pH optimum range between 6 and 8.5, was most active toward androstenediol, and least active toward pregnenolone. The estrogen sulfotransferase exhibited Michaelis-Menten kinetics (apparent Km = 4 microM). The neutral steroid sulfotransferase activity increased in velocity with increasing androstenediol or DHA concentration up to 1 microM beyond which considerable substrate inhibition occurred. It appears from these data that neutral steroid sulfates synthesized in the pig Leydig cell are not subject to enzymic desulfation in the same cells. 相似文献
11.
Yanaihara A Yanaihara T Toma Y Shimizu Y Saito H Okai T Higashiyama T Osawa Y 《Steroids》2001,66(2):87-91
Localization of steroid sulfatase, a membrane-bound microsomal enzyme, in human fallopian tubes was immunohistochemically investigated, and expression of RNA was confirmed by competitive RT-PCR. Human fallopian tubes were obtained from 10 patients in follicular and early luteal phases during gynecological laparotomy. An anti-human rabbit polyclonal antibody was prepared against sulfatase protein purified from human placenta. Total RNA was isolated from epithelium of fallopian tubes. A heterologous RNA competitor was designed, and competitive RT-PCR was carried out. Steroid sulfatase was localized to the cytoplasm of epithelial cells. With respect to the positive staining of cells, the number of positive secretory cells was higher than that of ciliated cells. A significantly higher number of positive cells was found in tissue obtained from the early luteal phase than that found in tissue from the follicular phase. An abundant expression of sulfatase mRNA in early luteal phase was also observed. This study demonstrates, for the first time, that steroid sulfatase is localized to human epithelial cells and that steroid sulfatase staining and mRNA expression changes with the menstrual cycle. These results suggest that sulfatase in the fallopian tube may be involved in controlling the local steroid environment, which appears to regulate aspects of the physiological reproductive function of the fallopian tube. 相似文献
12.
13.
Sulfatases are a highly conserved family of enzymes found in all three domains of life. To be active, sulfatases undergo a unique post-translational modification leading to the conversion of either a critical cysteine ("Cys-type" sulfatases) or a serine ("Ser-type" sulfatases) into a Calpha-formylglycine (FGly). This conversion depends on a strictly conserved sequence called "sulfatase signature" (C/S)XPXR. In a search for new enzymes from the human microbiota, we identified the first sulfatase from Firmicutes. Matrix-assisted laser desorption ionization time-of-flight analysis revealed that this enzyme undergoes conversion of its critical cysteine residue into FGly, even though it has a modified (C/S)XAXR sulfatase signature. Examination of the bacterial and archaeal genomes sequenced to date has identified many genes bearing this new motif, suggesting that the definition of the sulfatase signature should be expanded. Furthermore, we have also identified a new Cys-type sulfatase-maturating enzyme that catalyzes the conversion of cysteine into FGly, in anaerobic conditions, whereas the only enzyme reported so far to be able to catalyze this reaction is oxygen-dependent. The new enzyme belongs to the radical S-adenosyl-l-methionine enzyme superfamily and is related to the Ser-type sulfatase-maturating enzymes. This finding leads to the definition of a new enzyme family of sulfatase-maturating enzymes that we have named anSME (anaerobic sulfatase-maturating enzyme). This family includes enzymes able to maturate Cys-type as well as Ser-type sulfatases in anaerobic conditions. In conclusion, our results lead to a new scheme for the biochemistry of sulfatases maturation and suggest that the number of genes and bacterial species encoding sulfatase enzymes is currently underestimated. 相似文献
14.
A modulating role for antioxidants in desiccation tolerance 总被引:3,自引:0,他引:3
Most organisms depend on the availability of water. However, some life-forms, among them plants and fungi, but very few animals, can survive in the desiccated state. Here we discuss biochemical mechanisms that confer tolerance to desiccation in photosynthetic and non-photosynthetic organisms. We first consider damage caused by water removal and point out that free radicals are a major cause of death in intolerant tissue. Free radicals impair metabolism and necessitate protection and repair during desiccation and rehydration, respectively. As a consequence, desiccation tolerance and prolonged longevity in the desiccated state depend on the ability to scavenge free radicals, using antioxidants such as glutathione, ascorbate, tocopherols and free radical-processing enzymes. Some 'classic' antioxidants may be absent in lower plants and fungi. On the other hand, lichens and seeds often contain secondary phenolic products with antioxidant properties. The major intracellular antioxidant consistently found in all life forms is glutathione, making it essential to survive desiccation. We finally discuss the role of glutathione to act as a signal that initiates programmed cell death. The failure of the antioxidant system during long-term desiccation appears to trigger programmed cell death, causing ageing and eventual death of the organism. In turn, this suggests that a potent antioxidant machinery is one of the underlying mechanisms of desiccation tolerance. 相似文献
15.
Studies on the solubilization and purification of rat liver microsomal steroid sulfatase 总被引:1,自引:0,他引:1
S Burstein 《Biochimica et biophysica acta》1967,146(2):529-534
16.
Association of steroid sulfatase with one of the arylsulfatase C isozymes in human fibroblasts 总被引:1,自引:0,他引:1
P L Chang P A Varey N E Rosa M Ameen R G Davidson 《The Journal of biological chemistry》1986,261(31):14443-14447
When arylsulfatase C, a microsomal membrane-bound enzyme, is assayed with its natural substrates, the 3-beta-hydroxysteroid sulfates, it is also known as steroid sulfatase. Whether arylsulfatase C and steroid sulfatase are identical enzymes or not, however, has long been disputed. We now report that two electrophoretic variants of arylsulfatase C occur in normal human fibroblasts: one has a single anodic band of activity, s, and the other has an additional faster migrating band, f. The two types, s and f + s, occur in cells from either sex. When fibroblast strains with the f + s forms of arylsulfatase C were cloned, two types of primary clones were always obtained: s and f + s. A single f band was never seen. When these primary clones were subcloned, however, the arylsulfatase C phenotype remained unchanged: primary s clones gave rise to s subclones and f + s clones to f + s subclones only. Therefore, these forms were clonal in origin and demonstrated a novel inheritance pattern in human cultured cells. The appearance of increasing amounts of the f band was correlated with up to 4-fold increase of arylsulfatase C activity, whereas the steroid sulfatase activity remained constant, thus demonstrating that arylsulfatase C was not identical with steroid sulfatase activity. Polyclonal antibodies raised against the s form immunoprecipitated activities of the s form of arylsulfatase C and steroid sulfatase but not the f form of arylsulfatase C. Therefore, we conclude that only the s form of arylsulfatase C is immunologically related to steroid sulfatase so that arylsulfatase C per se is not necessarily identical with steroid sulfatase. In addition, a novel form of genetic heterogeneity of isozymes in human fibroblasts is demonstrated. 相似文献
17.
L Eriksson B Nilsson K Carlstr?m J Oscarsson S Eden B von Schoultz 《Journal of steroid biochemistry》1989,33(3):413-416
Steroid sulfatase activity was quantified in liver microsomes from hypophysectomized adult female rats treated with estradiol and continuous or intermittent human growth hormone (hGH). Hypophysectomy clearly enhanced sulfatase activity as compared to intact female rats. Normal female values were completely restored by continuous infusion of hGH (1.4 i.u./kg/day). Neither the same dose of hGH given as two daily injections nor estrogen replacement therapy had any effect. It is concluded that liver microsome sulfatase activity in the non-pregnant rat is regulated by the sexually dimorphic secretory pattern of GH. 相似文献
18.
Monique Bedin Dominique Weil Thérèse Fournier Lise Cedard Jean Frezal 《Human genetics》1981,59(3):256-258
Summary Steroid sulfatase activities are significantly higher in placentas obtained after the birth of girls than after the birth of boys, and also in female fibroblasts compared to male strains. This constitutes biochemical evidence for the non-inactivation of the X-linked sulfatase locus. No hydrolytic activity is found in the fibroblasts of ichthyotic boys. Heterozygosity is demonstrated in the fibroblasts of the four mothers studied, as they have steroid sulfatase activity of less or equivalent to the normal male value. 相似文献
19.
Calpains are a family of calcium-dependent intracellular cysteine proteases that regulate several physiological processes by limited cleavage of different substrates. The role of Calpain2 in embryogenesis is not clear with conflicting evidence from a number of mouse knockouts. Here we report the temporal and spatial expression of Calpain2 in Xenopus laevis embryos and address its role in Xenopus development. We show that Calpain2 is expressed maternally with elevated expression in neural tissues and that Calpain2 activity is spatially and temporally regulated. Using a Calpain inhibitor, a dominant negative and a morpholino oligonoucleotide we demonstrate that impaired Calpain2 activity results in defective convergent extension both in mesodermal and neural tissues. Specifically, Calpain2 downregulation results in loss of tissue polarity and blockage of mediolateral intercalation in Keller explants without affecting adherens junction turnover. We further show that Calpain2 is activated in response to Wnt5a and that the inhibitory effect of Wnt5a expression on animal cap elongation can be rescued by blocking Calpain2 function. This suggests that Calpain2 activity needs to be tightly regulated during convergent extension. Finally we show that expression of Xdd1 blocks the membrane translocation of Calpain2 suggesting that Calpain2 activation is downstream of Dishevelled. Overall our data show that Calpain2 activation through the Wnt/Ca2+ pathway and Dishevelled can modulate convergent extension movements. 相似文献
20.
A new microbial degradation pathway of steroid alkaloids 总被引:1,自引:0,他引:1
In the degradation pathway of the steroid alkaloid tomatidine by Gymnoascus reesii the A-ring of tomatidine is opened with the formation of the 4-hydroxy-3,4-secotomatidine-3-oic acid, which was identified in the form of N-acetyl-3,4-tomatidine-carbolactone by mass, IR and 1H NMR spectra. Cleavage of the A-ring in the starting reaction indicates that an alternative pathway must be operating, instead of the general oxidative one. 相似文献