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A M Kaye

Publications and source records attributed to A M Kaye.

At least 73 records · Page 4Linked to original sources

Estrogen-induced creatine kinase in the reproductive system of the immature female rat.

An increase in the biosynthetic rate of the brain-type isozyme of creatine kinase (CKBB, first described in the uterus as the "estrogen-induced protein") was found in the ovary, vagina and estrogen receptor-rich regions of the brain (preoptic area, anterior hypothalamus and median eminence), one hour after injection of 5 micrograms of estradiol-17 beta into 25-28 day-old rats. The increase in synthetic rate in the ovary, detected by 35S methionine incorporation, peaked at 1h, but still remained higher than in control ovaries at 6 h and was reflected in a longer-term increase in ovarian CK specific activity after 4 daily injections. Both ovary and vagina, similarly to brain, contained exclusively the BB isozyme of CK. These findings suggest that the entire female reproductive system can respond to estrogen by a rapid induction of CKBB.

Animals↗

Enzyme induction by estrogen.

The injection of estrogen into an immature or ovariectomized rat results in an increase in the specific activities of many uterine enzymes which can be detected, usually, within hours to days. The recent identification of the "estrogen-induced protein" as the brain type isozyme of creatine kinase (CKBB), provided an easily measurable enzyme marker, the mRNA of which doubles 1 h after estrogen injection. The increase in synthesis of CKBB from a high constitutive rate to a several-fold higher induced rate may be a more general response to hormonal stimulation in a mammalian system than the "all or none" induction exemplified by bacterial systems. This rapid estrogen-induced increase in the rate of CKBB synthesis is now reported in several rat reproductive organs; ovary, uterus, vagina and estrogen receptor-rich regions of the hypothalamus (anterior hypothalamus and median basal eminence) and preoptic areas, as well as in normal human breast tissue and in human breast tumors. The rapidity of CKBB induction makes it a favorable candidate marker for developing a cell-free induction system to study the interaction of the estrogen-receptor complex with specific loci in chromatin. For this purpose, molecular cloning of cDNA for CKBB is now under way.

Animals↗

Identification of the major component of the estrogen-induced protein of rat uterus as the BB isozyme of creatine kinase.

We have recently shown that the estrogen-induced protein of rat uterus (IP) is indistinguishable from a constitutive protein in rat brain, and that the brain type gamma gamma isozyme of enolase (EC 4.2.1.11) is a component of IP. Here we report that the brain type BB isozyme of creatine kinase (EC 2.7.3.2) is the major component of IP. The two IP components, creatine kinase BB and enolase gamma gamma, were copurified from rat brain by ammonium sulfate fractionation and DEAE-cellulose chromatography. The enzymes were separated on reactive blue 2 agarose, which absorbs creatine kinase BB but not enolase gamma gamma, at 40 mMNaCl, pH 5.2. The major component of IP was identified as the BB isozyme of creatine kinase on the basis of its specific enzyme activity, chromatographic behavior, and specific immunoprecipitation by anti-creatine kinase BB antiserum. The identity of the major component of IP and creatine kinase BB was confirmed by double isotope ratio analysis, limited protease digestion patterns, and the rapid increase in the rate of synthesis of creatine kinase in rat uterus in response to estrogen. IP has been a favored marker for estrogen action in rat uterus because of its early response to the hormone both in vivo and in vitro. The identification of the major component of IP as the BB isozyme of creatine kinase is a step toward understanding the function of IP in the early responses of the uterus to estrogen and reveals a further advantage for IP as a marker for the study of gene expression, and as a possible enzymic marker for hormone responsive tumors.

Animals↗

mRNA for the rat uterine estrogen-induced protein. Translation in vitro and regulation by estrogen.

Poly(A)-rich RNA was isolated from uterus and brain of immature rats and translated in the rabbit reticulocyte lysate cell-free protein-synthesizing system. The translation products were analyzed by 1) specific immunoprecipitation using antibodies directed against purified estrogen-induced protein (IP), 2) two-dimensional gel electrophoresis, and 3) partial protease digestion of selected spots from two-dimensional gels. These analyses showed that IP mRNA from both uterus and brain is faithfully translated in the cell-free system. Comparison of translation products derived from uterine mRNA of untreated and 1-h estrogen-treated rats revealed a specific increase in the ability of mRNA from treated animals to direct the synthesis of IP. Thus, estrogen stimulation of IP synthesis results, at least partly, from increased uterine concentrations of IP mRNA.

Animals↗

Nafoxidine-responsive uterine protein: further characterization and distinction from the "estrogen-induced" protein (IP).

In a previous paper, we reported that nafoxidine (UA) stimulated the synthesis of a uterine protein showing the same electrophoretic mobility as the "estrogen-induced protein" (E2-IP) first described by Notides and Gorski. In the present work, we analyzed the IP-containing electrophoretic zone by SDS polyacrylamide-gel electrophoresis, and found that estradiol-17 beta (E2) and nafoxidine stimulated the synthesis of different proteins. As expected, estradiol-17 beta stimulated the synthesis of the E2-IP of 46 000 Mr. On the other hand, UA stimulated the synthesis of 27 000 and 30 000 Mr proteins (UA-IP). These UA-IP were not precipitated by an antiserum raised against E2-IP. Therefore, UA-IP appear to be independent entities and not degradation or precursor products of E2-IP. Both UA-IP are constitutively present in the uterus and even in higher relative amounts in rat brain. The present finding, that an "anti-estrogen", such as nafoxidine, stimulates the synthesis of different proteins than estrogen, provides a new approach to the study of the molecular mechanism of estrogen action.

Animals↗

Steroid-induced proteins in human endometrium.

The synthesis of soluble proteins in human endometria at various phases of menstrual cycle was evaluated by polyacrylamide gel electrophoresis of [35S]methionine-labeled proteins. Densitometric analysis of the gels revealed alterations in the rate of synthesis of single protein bands throughout the cycle. Administration of conjugated estrogens (Premarin) to women undergoing hysterectomy, or exposure, in vitro, of the endometrial tissue to 17 beta-estradiol produced an increased incorporation of [35S]methionine into a specific protein which migrated on SDS-polyacrylamide gels at a molecular weight of about 55 000. Induction of this protein was observed only in those endometria showing a secretory histological appearance. The protein was resolved into at least 2 different spots in two-dimensional gel electrophoresis. An increase in the rate of synthesis of another endometrial protein with an apparent molecular weight of 51 000 was observed in tissues exposed in vitro to medroxyprogesterone acetate. These steroid-induced proteins may be a useful marker for studying hormone action in both normal and neoplastic endometria.

Electrophoresis, Polyacrylamide Gel↗

Replenishment and nuclear retention of oestradiol-17 beta receptors in rat uteri during postnatal development.

1. Uteri of 6--10-day-old rats do not show a late growth response to oestrogen (increase in rate of DNA synthesis and cell division) exhibited by fully competent (20 days or older) uteri. We posed the question whether the lack of the late growth response is due to an inability to replenish the cytoplasmic pool of oestrogen receptors or to curtailed retention of oestrogen binding in the nucleus. Uterine nuclear and cytoplasmic receptors were measured by a [3H]oestradiol-17 beta exchange assay, at 1, 3, 6, 14 and 24 h after oestrogen injection. 2. The replenishment of cytoplasmic oestrogen receptors showed a similar pattern in the uteri of 6 and 10-day-old (partially responsive) and in 20-day-old (fully responsive) rats. 3. Oestrogen was retained longer in uterine nuclei obtained from 5 and 10-day-old rats than in uterine nuclei of 20 and 25-day-old rats. 4. Oestrogen receptors resistant to 0.4 M KCl extraction (residual receptors) were found in uterine nuclei of 6 and 25-day-old rats after oestrogen injection at all the times tested. The concentration of these residual receptors during the late period (6--24 h after injection) was not significantly different in uterine nuclei of 6-day-old and 25-day-old rats. 5. We conclude that neither lack of oestrogen receptor replenishment nor curtailed retention of oestrogen binding in the nucleus is the factor which limits the complete responsiveness to oestrogen in uteri of rats during postnatal development.

Aging↗

Synthesis of tubulin and actin by neuronal and glial nuclear preparations from devloping rat brain.

A system was established in which nuclear preparations from rat brains were capable of protein synthesis under cell-free conditions. The electrophoretic pattern of the synthesized proteins was similar to that found in vivo provided that the reaction mixture contained pH 5 precipitated factors derived from the high speed supernatant fraction of brain. In the absence of the pH 5 factors, using nuclear preparations from brains of 2-day-old rats, approximately 1.5% and 2% of the newly synthesized proteins were identified as tubulin and actin, respectively. In the presence of pH 5 factors, protein synthesis was stimulated and the proportion of the newly synthesized tubulin and actin increased to 26% and 11%, respectively. In contrast to nuclear fractions from 2-day-old rats, when nuclei from brains of 1-month-old rats were tested in the presence of pH 5 factors, the proportion of tubulin and actin synthesized was lower and amounted to 10% and 4%, respectively. The age-dependent change in the relative amount of the tubulin and actin synthesized is in good agreement with the translational pattern shown by brain polyribosomes in a brain cell-free system as well as with the pattern obtained with brain mRNA translated in a wheat germ cell-free system. Nuclei enriched for either neuronal or glial populations synthesized similar proportions of tubulin and actin in vitro. We conclude that the reduction in the synthesis of tubulin and actin during the postnatal development of the rat brain occurs in both neuronal and glial cells.

Actins↗

Demonstration of 8 S-cytoplasmic oestrogen receptor in rat mullerian duct.

1. High affinity macromolecular binding of the non-steroidal synthetic oestrogen [3H]diethylstilboestrol and of [3H] oestradiol-17beta in cytosol of Müllerian duct and uterus, and in blood plasma of perinatal rats, was investigated by sucrose density gradient sedimentation. 2. While [3H] oestradiol was bound to both the characteristic 8 S uterine cytoplasmic receptor and a 4 S component of uterine cytosol and plasma of 11-day-old rats, [3H] diethylstilboestrol was bound almost exclusively by the 8 S cytoplasmic receptor. 3. The greatly reduced binding of [3H] diethylstilboestrol to the 4 S plasma plasmic receptor in the Müllerian duct (precursor of the uterus) of 20-day-old foetuses.

Animals↗

Specificities in the synthesis of a cytoplasmic estrogen-induced uterine protein.

The earliest known induction by estrogen of a specific uterine protein is that of the induced protein (IP) of Gorski and colleagues, which is demonstrable within 40 min after treatment. We found that this protein is not restricted to the rat; it was detected i the uterus of prepuberal C3H/eB and SWR mice, 1 h after injection of 4 B5g/rat) and coumestrol (300B5g/rat) and the synthetic estrogen diethylstilbestrol (5 B5/rat). We found no significant increase in the stimulation of the rate of IP synthesis by estrogen in uteri from either 10- or 20--day-old rats on subsequent treatment with actinomycin D, indicating that there was no superinduction of IP, despite a previous claim.

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Separation of "estrogen-induced" protein from phosphoprotein phosphatase activity of immature rat uterus.

Preparations of the "induced protein" which appears in the rat uterus within 40 min of estradiol administration have recently been reported to contain phosphoprotein phosphatase (phosphoprotein phosphohydrolase, EC 3.1.3.16) activity. We found that these two proteins distribute differently on ammonium sulfate fractionation of uterine cytosol. Preparative cellulose acetate electrophoresis afforded complete (greater than 99.9%) separation of phosphoprotein phosphatase activity from the induced protein. The specific activity of phosphoprotein phosphatase in uterine cytosol was unchanged 1, 4, 12, or 24 hr after estradiol administration. These results are incompatible with the view that the induced protein mediates estrogen action by virtue of an inherent phosphoprotein phosphatase activity.

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