Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Isoenzymes of beta-galactosidase and of N-acetyl-beta-glucosaminidase were assayed during development of rat testis and as a function of hormonal treatments. Isoenzyme 1 of beta-galactosidase was highest in specific activity in the 4-day-old testis, at a point when Sertoli cells and gonocytes were the predominant cell type. Beta-galactosidase II, previously shown to be associated with the sperm acrosome, was undetectable through the spermatocyte stage of development, but increased in specific activity during the formation of spermatids. The specific activities of isoenzymes I and II of N-acetyl-beta-glucosaminidase increased markedly in association with the formation of spermatogonia and spermatocytes, and then declined with the appearance of spermatids. Following hypophysectomy of rats at 26 days of age or in adulthood the specific activities of the lysosomal enzymes beta-galactosidase I and N-acetyl-beta-glucosaminidase I and II increased markedly, while the acrosomal beta-galactosidase II was undetectable. The normal patterns of isoenzyme distributed were restored completely by administration of LH and FSH or testosterone to hypophysectomized animals. These results thus demonstrate specific patterns of isoenzyme concentration during spermatogenesis. Formation of the acrosome in developing spermatids is associated with the induction of new forms of beta-galactosidase (isoenzyme II) and N-acetyl-beta-glucosaminidase (sperm isoenzyme). These molecules appear to be specialized forms which may participate in fertilization, and their induction is dependent upon the actions of gonadotropins or testosterone.
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PMID:Hormonal regulation of isoenzymes of N-acetyl-beta-glucosaminidase and beta-galactosidase during spermatogenesis in the rat. 112 Apr 77

A panel of three bispecific monoclonal antibodies (bsMAbs) binding to follitropin (FSH) and to beta-galactosidase have been prepared by fusion of hybridoma cell lines resistant to oubain and neomycin. One of these bispecific antibodies contains heavy chains of the same IgG subclass, and two are composed of heavy chains of different IgG subclasses. We have investigated methods for the purification of bispecific antibodies from hybrid hybridoma supernatant fluids grown in serum-free medium. Following ammonium sulfate precipitation, bispecific antibodies can be purified in a single step by mixed mode ion-exchange HPLC on Bakerbond Abx columns. In one case, three species were resolved by ion-exchange HPLC and functional analysis showed that two peaks contained parental antibodies, and the third contained the bispecific. Ion-exchange HPLC purification of serum-free preparations from two other hybrid hybridomas resolved seven protein-containing peaks, only one of which was active in a bispecific ELISA. The equilibrium affinity constants for each of the parental antibodies for both FSH and beta-galactosidase were determined and found to be similar to those of the purified bsMAbs. Further, the association of FSH to one binding site on a bispecific antibody was shown to have no effect on the equilibrium binding constant for beta-galactosidase binding to the other site. Our results suggest that bsMAbs can be readily purified from hybrid hybridomas by a simple and rapid method, and the binding of antigen to one binding site on a bsMAb is independent of antigen binding to the second site.
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PMID:Antigen binding properties of highly purified bispecific antibodies. 152 92

The serum concentrations of FSH, LH, prolactin, testosterone, and estradiol and the enzymatic activities of hyaluronidase, glucosidases (alpha-glucosidase, beta-glucosidase, alpha-mannosidase, N-acetyl-beta-D-glucosaminidase, beta-glucuronidase, and beta-galactosidase), lactate dehydrogenase and its isoenzymes (LDH1, LDH2, LDH3, LDH-X, LDH4), and total proteins were measured in the semen of 69 subjects (8 normozoospermic controls, 7 secretory, and 54 excretory azoospermic subjects). FSH levels rose with the deterioration in spermatogenesis and served to differentiate the secretory from the excretory azoospermias. The only source of hyaluronidase and LDH-X in the ejaculate is the spermatozoa. alpha-Glucosidase activity essentially originates in the epididymis. The seminal determination of alpha-glucosidase and, to a lesser extent, alpha-mannosidase and N-acetyl-beta-D-glucosaminidase helps rapidly, sensitivity, reliably, and noninvasively to differentiate secretory azoospermias (with higher enzymatic activity) from the excretory type (less enzymatic activity) and may be of use in identifying with a certain degree of reliability the site of obstruction in the male genital tract.
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PMID:Enzyme and hormonal markers in the differential diagnosis of human azoospermia. 153 Mar 67

Three equine CG (eCG) forms with identical amino acid sequences but different mol wt and monosaccharide compositions were isolated from a crude eCG preparation and designated eCG-L (low mol wt), eCG-M (medium mol wt), and eCG-H (high mol wt). No differences in primary structure between each form and the known sequence of eCG were observed. SDS-PAGE of these preparations under reducing conditions revealed that the mol wt differences between them were due only to the different sizes of their beta-subunits. Carbohydrate compositions suggested an increase in O-glycosylation in the higher mol wt forms. N-Linked glycopeptide fragments obtained from eCG beta-subunits by endoproteinase Lys-C digestion had identical electrophoretic mobilities. Thus, the different molecular sizes of the beta-subunits were associated only with disparities in O-glycosylation of their C-terminal extension. When tested in a LH and several FSH radioligand assay systems, eCG-H proved to have significantly lower receptor-binding activities than eCG-L and eCG-M. Endo-beta-galactosidase digestion increased the FSH receptor-binding activity of all eCG forms; however, partially deglycosylated eCG-H remained the least active form. Thus, the O-linked oligosaccharides of eCG-H exert a negative influence on its receptor-binding activity.
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PMID:Negative influence of O-linked oligosaccharides of high molecular weight equine chorionic gonadotropin on its luteinizing hormone and follicle-stimulating hormone receptor-binding activities. 864 Dec 7

Activin is a dimeric glycoprotein hormone that was initially characterized by its ability to stimulate pituitary FSH secretion and was subsequently recognized as a growth factor with diverse biological functions in a large variety of tissues. In the testis, activin has been implicated in the auto/paracrine regulation of spermatogenesis through its cognate cell membrane receptors on Sertoli and germ cells. In this study we provide evidence for intranuclear activin/inhibin betaA subunit and show its distribution in the rat seminiferous epithelium. We have shown by transient expression in HeLa cells of beta-galactosidase fusion proteins that the betaA subunit precursor contains a functional nuclear localization signal within the lysine-rich sequence corresponding to amino acids 231-244. In all stages of the rat seminiferous epithelial cycle, an intense immunohistochemical staining of nuclear betaA was demonstrated in intermediate or type B spermatogonia or primary spermatocytes in their initial stages of the first meiotic prophase, as well as in pachytene spermatocytes and elongating spermatids primarily in stages IX-XII. In some pachytene spermatocytes, the pattern of betaA immunoreactivity was consistent with the characteristic distribution of pachytene chromosomes. In the nuclei of round spermatids, betaA immunoreactivity was less intense, and in late spermatids it was localized in the residual cytoplasm, suggesting disposal of betaA before spermatozoal maturation. Immunoblot analysis of a protein extract from isolated testicular nuclei revealed a nuclear betaA species with a molecular mass of approximately 24 kDa, which is more than 1.5 times that of the mature activin betaA subunit present in activin dimers. These results suggest that activin/inhibin betaA may elicit its biological functions through two parallel signal transduction pathways, one involving the dimeric molecule and cell surface receptors and the other an alternately processed betaA sequence acting directly within the nucleus. According to our immunohistochemical data, betaA may play a significant role in the regulation of nuclear functions during meiosis and spermiogenesis.
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PMID:Identification of a nuclear localization signal in activin/inhibin betaA subunit; intranuclear betaA in rat spermatogenic cells. 1002 3

Although usually considered to be a constitutively expressed protein, in the primate ovary the expression of CREB (cAMP response element-binding protein) is extinguished after ovulation, and its loss is temporally associated with the cessation of proliferation of luteal cells and the ultimate commitment of the corpus luteum to undergo regression. To determine the cellular consequences of the loss of CREB expression, we expressed a nonphosphorylatable mutant of CREB (CREB M1) in primary cultures of rat granulosa cells using a replication-defective adenovirus vector. Expression of CREB M1 did not block granulosa cell differentiation as assessed by acquisition of the ability to produce estrogen and progesterone in response to FSH or forskolin. However, granulosa cells expressing CREB M1, but not adenovirus-directed beta-galactosidase or enhanced green fluorescent protein, exhibited a 35% reduction in viability that was further reduced to 65% after stimulation with 10 microM forskolin. These results demonstrate that the trophic effects of cAMP (proliferation and survival) on ovarian granulosa cells are functionally separate from the effects of cAMP on differentiation and provide novel evidence that CREB may function as a cell survival factor in the ovary. The separation of signaling pathways that govern differentiation and survival in the ovary thereby provides a mechanism by which progesterone production, which is absolutely essential for the maintenance of pregnancy, can continue despite the cessation of proliferation of luteal cells and their commitment to cell death (luteolysis).
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PMID:Adenovirus-directed expression of a nonphosphorylatable mutant of CREB (cAMP response element-binding protein) adversely affects the survival, but not the differentiation, of rat granulosa cells. 1044 9