Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously demonstrated that human placental fibroblasts produce a pregnancy-specific beta 1-glycoprotein (PS beta G) immunologically indistinguishable from placental PS beta G. This was confirmed by the immunocytochemical localization of PS beta G in these fibroblasts. In addition, placental fibroblasts contain all three PS beta G mRNAs of 2.3, 2.2, and 1.7 kilobases which hybridize with the three PS beta G cDNAs (PSG16, PSG93, and PSG95) identified, although at 1.4-2.5% of the levels in human term placenta. The major PS beta G species synthesized by placental fibroblasts is a 62K glycopolypeptide formed from a 58K intracellular precursor polypeptide. However, the PS beta G species found in human placenta are one major glycoprotein of 72K and two minor ones of 64K and 54K. Poly(A)+ RNA from placental fibroblasts directed the synthesis of two polypeptides of 48K and 46K (major), whereas, poly(A)+ RNA from human placenta directed the synthesis of higher levels of four polypeptides of 50 K, 48 K (major), 46 K, and 36 K. Thus, the major PS beta G species found in fibroblasts and human placenta differ. The carbohydrate side-chains are essential for the stability of fibroblast PS beta G, because PS beta G synthesis in these fibroblasts could not be detected in the presence of tunicamycin, a protein glycosylation inhibitor which did not affect PS beta G mRNA expression. Our finding that a variant PS beta G species is produced in placental fibroblasts raises the possibility that the authentic placental PS beta G species may have different functions.
Mol Endocrinol 1989 Jan
PMID:Characterization of pregnancy-specific beta 1-glycoprotein synthesized by human placental fibroblasts. 249 35

The ability of high doses of cortisol to retard the involution process in the rat ventral prostate was related to alterations in the pattern of gene expression. Poly(A)+ RNA preparations from the prostates of noncastrated, castrated, and castrated rats injected daily for 7 days with cortisol were compared by Northern blot hybridizations for the relative expression of genes associated with cell differentiation and maintenance (the C1 prostatic steroid binding protein gene and alpha-tubulin), with cell death (TRPM-2, hsp 70, and c-fos), and with hormone regulation (the androgen and glucocorticoid receptors). As anticipated, the concentration of C1 mRNA in the prostate fell to less than 4% of that in the noncastrated controls within 4 days after castration and was nearly undetectable after 7 days. This decline was retarded by cortisol treatment of 7-day castrated animals which sustained the level of C1 transcripts at approximately 50% of control. While the pattern of expression of alpha-tubulin indicated some minor fluctuations, with the highest level occurring 7 days after castration, the prostates of the cortisol-treated group had essentially the same concentration of this mRNA as the noncastrates. Cortisol also modified the expression of genes associated with prostatic cell death. The large increase in prostatic TRPM-2 mRNA, seen 7 days after castration, was reduced by over 80% after treatment with the glucocorticoid. Although not as abundantly expressed as TRPM-2, the castration-induced levels of transcripts for both hsp 70 and the protooncogene c-fos were substantially reduced by cortisol.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Endocrinol 1989 Apr
PMID:Cortisol alters gene expression during involution of the rat ventral prostate. 249 51

Poly(ADP-ribose)polymerase is a chromatin-associated enzyme of eukaryotic cell nuclei that catalyses the covalent attachment of ADP-ribose units from NAD+ to various nuclear acceptor proteins. This post-translational modification has been postulated to influence several chromatin functions, particularly those where nicking and rejoining of DNA occur. Poly(ADP-ribosyl)ation reactions are strictly dependent upon the presence of interruptions on DNA. We have recently demonstrated that the DNA-binding domain of the protein containing two putative "zinc-fingers" binds DNA in a zinc-dependent manner. The basis for the recognition of the DNA strand breaks by this enzyme, and more precisely, its 29,000 Mr N-terminal part, which contains the metal binding sites, needed to be clarified. DNA probes harbouring a single strand interruption at a defined position were constructed from synthetic oligonucleotides. DNase I protection studies show that poly(ADP-ribose)polymerase specifically binds to a DNA single-strand break by its metal-binding domain depending upon the presence of Zn(II). These results support the idea that the enzyme participates to the maintenance of DNA integrity in eukaryotes.
J Mol Biol 1989 Nov 05
PMID:Zinc-binding domain of poly(ADP-ribose)polymerase participates in the recognition of single strand breaks on DNA. 251 29

Poly(A) polymerases (PAPs) from HeLa cell cytoplasmic and nuclear fractions were extensively purified by using a combination of fast protein liquid chromatography and standard chromatographic methods. Several forms of the enzyme were identified, two from the nuclear fraction (NE PAPs I and II) and one from the cytoplasmic fraction (S100 PAP). NE PAP I had chromatographic properties similar to those of S100 PAP, and both enzymes displayed higher activities in the presence of Mn2+ than in the presence of Mg2+, whereas NE PAP II was chromatographically distinct and had approximately equal levels of activity in the presence of Mn2+ and Mg2+. Each of the enzymes, when mixed with other nuclear fractions containing cleavage or specificity factors, was able to reconstitute efficient cleavage and polyadenylation of pre-mRNAs containing an AAUAAA sequence element. The PAPs alone, however, showed no preference for precursors containing an intact AAUAAA sequence over a mutated one, providing further evidence that the PAPs have no intrinsic ability to recognize poly(A) addition sites. Two additional properties of the three enzymes suggest that they are related: sedimentation in glycerol density gradients indicated that the native size of each enzyme is approximately 50 to 60 kilodaltons, and antibodies against a rat hepatoma PAP inhibited the ability of each enzyme to function in AAUAAA-dependent polyadenylation.
Mol Cell Biol 1989 Oct
PMID:Multiple forms of poly(A) polymerases purified from HeLa cells function in specific mRNA 3'-end formation. 255 86

CBP1 is a yeast nuclear gene encoding a mitochondrial protein that stabilizes the 5' end of cytochrome b (cob) pre-mRNA. Cytochrome b is the only mitochondrially synthesized component of the respiratory chain complex III. Since the nuclearly encoded subunits of this complex are regulated at the transcriptional level by catabolite repression, we hypothesized that CBP1 might be similarly regulated. To test the idea that transcriptional regulation of CBP1 could coordinate an increase in cytochrome b mRNA stability with an increase in nuclearly encoded complex III subunit production, we characterized the change in abundance of CBP1 mRNA during derepression on a nonfermentable carbon source. Poly(A)+ RNA from derepressed yeast cells was examined by Northern (RNA) analyses with cRNA probes from CBP1. Both 2.2- and 1.3-kilobase (kb) transcripts were detected. The 1.3-kb mRNA lacked approximately 900 nucleotides of the 3' end of the 2.2-kb mRNA, which encodes the carboxyl-terminal 250 amino acid residues of the CBP1 coding sequence. Northern analyses of RNA isolated from deletion-insertion mutants of CBP1 and from strains that overexpress CBP1 mRNA demonstrated that both mRNAs were transcribed from the CBP1 gene. Furthermore, we demonstrated that the levels of the two CBP1 mRNAs were reciprocally regulated by the carbon source in the growth medium. This is the first description of a yeast gene from which two transcripts that can encode proteins with distinctly different coding properties are generated by alternative 3'-end formation.
Mol Cell Biol 1989 Oct
PMID:The yeast CBP1 gene produces two differentially regulated transcripts by alternative 3'-end formation. 257 26

Poly(A)+RNA-DNA hybrids complementary to mobile dispersed genetic elements MDG 1 and MDG 3 have been isolated from Drosophila melanogaster culture cells. DNA and RNA in these complexes are represented by perfect hybrids. Three types of single-stranded DNA are detected in these hybrids: full-length DNA molecules of MDG containing one and two long terminal repeats (minus strand) and the long terminal repeat itself (plus strand). The results are consistent with the model of reverse transcriptional replication of MDG similar to that of retroviruses.
Mol Biol (Mosk)
PMID:[Detection of intermediates of RNA reverse transcription for mobile dispersed MDG 1 and MDG 3 genes in Drosophila cells]. 258 Feb 23

In order to investigate the mechanism underlying ovarian steroid action on gene expression of hypothalamic luteinizing hormone releasing hormone (LHRH), changes in LHRH mRNA level were determined by RNA-blot hybridization assay. Twenty-eight-day-old female rats were ovariectomized (OVX) and implanted with Silastic capsule containing either 17 beta-estradiol (E) or vehicle (V). Two days later (day 30), OVX + E-primed rats were given s.c. progesterone (P, 1 mg) 6 h prior to decapitation. Four experimental groups were studied: (1) intact, (2) OVX + V, (3) OVX + E, and (4) OVX + E + P-treated rats. Poly(A) RNA fractions from hypothalami (40-50/group) were isolated, blotted onto nitrocellulose paper and hybridized with 32P-end-labeled LHRH oligonucleotides (29 mer) which are complementary to rat LHRH mRNA. The hypothalamic LHRH mRNA signal markedly attenuated 2 days following ovariectomy. E replacement to OVX rats slightly increased LHRH mRNA level, which is lower than that of the intact group. However, a single injection of P to OVX + E-treated rats notably augmented the LHRH mRNA level over that observed in the intact group. In addition, LHRH content and release in vitro were examined to correlate with changes in LHRH gene expression. Ovariectomy and the replacement of E and/or P resulted in a similar fashion of changes in LHRH release and content as compared to alteration of LHRH mRNA level. This study clearly demonstrates that P increases LHRH mRNA level in the hypothalamus of OVX + E-primed immature rats.(ABSTRACT TRUNCATED AT 250 WORDS)
Brain Res Mol Brain Res 1989 Nov
PMID:Progesterone increases messenger ribonucleic acid (mRNA) encoding luteinizing hormone releasing hormone (LHRH) level in the hypothalamus of ovariectomized estradiol-primed prepubertal rats. 269 78

Thirty to 40% of estrogen receptor (ER) positive human breast tumors are resistant to endocrine therapy. To investigate the possibility that abnormal ER proteins may be associated with this endocrine resistant phenotype we have looked for the presence of abnormally sized ER mRNA in human breast tumor biopsies. Poly(A+) enriched RNA was isolated from 46 human breast tumor biopsies and analyzed by Northern blotting and hybridization with the human estrogen receptor OR-8 cDNA. Seventy percent of the tumors contained detectable 6.5 kilobase (kb) ER mRNA. Some tumors also contained smaller sized ER mRNA of approximately 3.8 and 2.4 kb. These variant sized transcripts were only detected in biopsies where the normal 6.5 kb mRNA was present. In some cases the abundance of the variant mRNAs was equal to or greater than the normal ER mRNA. The variant ER mRNAs were not due to nonspecific RNA degradation nor was there any evidence of gross alteration of the ER gene in tumors where variant mRNAs were detected. ER cDNA fragments representing only the E/F domain of the receptor showed little or no hybridization with the variant sized ER mRNAs, while a ER cDNA fragment covering the A/B, C and D domains hybridized to both the variant and normal ER mRNAs. This suggested that the smaller variant ER mRNAs may be missing some or all of the E/F domain which is thought to contain the steroid hormone binding domain of the receptor. It is hypothesized that if these intermediates were translated into viable proteins they may interfere with the normal ER function.
Mol Endocrinol 1989 Apr
PMID:Variant estrogen receptor mRNA species detected in human breast cancer biopsy samples. 272 32

Detachment of flagella in Chlamydomonas reinhardii stimulates a rapid accumulation of tubulin mRNAs. The induced tubulin mRNAs are normally rapidly degraded following flagellar regeneration, but inhibition of protein synthesis with cycloheximide prevents their degradation. alpha-Tubulin poly(A) tail lengths were measured during normal accumulation and degradation, and in cycloheximide-treated cells. To measure alpha-tubulin mRNA poly(A) chain lengths with high resolution, specific 3' fragments of alpha 1- and alpha 2-tubulin mRNAs, generated by RNase H digestion of mRNA-oligonucleotide hybrids, were sized by Northern analysis. Both alpha-tubulin mRNAs have a newly synthesized poly(A) chain of about 110 adenylate residues. The poly(A) tails shorten with time, and show an average length of 40 to 60 adenylate residues by 90 minutes after deflagellation, at which time induced alpha-tubulin mRNA is being rapidly degraded. Poly(A) loss is significantly accelerated in cycloheximide-treated cells, and this loss is not attributible simply to the longer time the stabilized molecules spend in the cytoplasm. A large fraction of alpha-tubulin mRNA accumulates as mRNA with very short poly(A) tails (less than 10 residues) in the presence of cycloheximide, indicating that deadenylated alpha-tubulin mRNAs can be stable in vivo, at least in the absence of protein synthesis. The rate and extent of poly(A) loss in cycloheximide are greater for alpha 2-tubulin mRNA than for alpha 1-tubulin mRNA. This difference cannot be attributed to differential ribosome loading. This finding is interesting in that the two mRNAs are very similar in sequence with the exception of their 3' untranslated regions.
J Mol Biol 1989 Jun 20
PMID:Accelerated poly(A) loss on alpha-tubulin mRNAs during protein synthesis inhibition in Chlamydomonas. 276 Sep 30

Molecular hybridization was used to measure poly(A)-containing mRNA and insulin mRNA, and to evaluate viral persistence, in pancreatic beta cells of coxsackievirus B4-induced diabetic mice. Cellular RNA was hybridized with [3H]poly(U) to measure poly(A)-containing total mRNA, 32P-labeled preproinsulin I and II probes to measure insulin mRNA, and a 32P-labeled virus-specific probe to evaluate persistence. The infected mice (80-90%) showed subnormal blood glucose at 72 h postinfection and were hyperglycemic at 6 and 8 weeks. Poly(A)-containing total mRNA decreased by about 26% at 72 h and 6 weeks and by 49% at 8 weeks, while preproinsulin I mRNA by 30% and preproinsulin II by 46% at 8 weeks postinfection compared to control. Viral sequences were abundant at 72 h and in fair amounts later. It appears that persistent viral infection produces a pathological state, which impairs beta cell function to reduce insulin mRNA and consequently insulin synthesis apparently leading to hyperglycemia.
Mol Cell Endocrinol 1988 Feb
PMID:Insulin mRNA content in pancreatic beta cells of coxsackievirus B4-induced diabetic mice. 283 17


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