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)

cDNAs encoding the precursor molecule of the turkey LH beta subunit (tLH beta) were cloned from a turkey pituitary cDNA library. The nucleotide sequence of the longest of two different tLH beta cDNA clones contained 592 bp, and included 23 bp of the 5' untranslated region (UTR) and 92 bp of the 3' UTR in addition to a 477 bp open reading frame that encoded a 39 amino acid leader polypeptide and a 120 amino acid mature apoprotein. Turkey and chicken LH beta sequences shared approximately 92 and 93% nucleotide and amino acid sequence similarities respectively. Northern blot analysis of total cellular anterior pituitary RNA showed that an approximate 800 base transcript hybridized to a 32P-labelled tLH beta cDNA probe. The gonadotrophin-releasing hormone (GnRH)- and prolactin (PRL)-regulated expression of LH and PRL in dispersed pituitary cells was determined by Northern blot analysis of tLH beta and PRL steady-state mRNA levels and by RIA analysis of secreted LH and PRL. GnRH-treated cells showed increased levels of both tLH beta mRNA and secreted LH, whereas mRNA and secreted levels of PRL did not change significantly. Cells treated with PRL showed lower levels of tLH beta and PRL mRNA as well as decreased release of LH and PRL. When cells were treated with both PRL and GnRH, increases in tLH beta mRNA and secreted levels of LH observed with GnRH alone were negated, whereas the decreases in mRNA and secreted levels of PRL observed with PRL alone were abrogated. These findings suggest that PRL can down-regulate tLH beta gene expression and spontaneous release of LH as well as autoregulate PRL gene expression and spontaneous release of PRL, while GnRH appears capable of modulating the effects of PRL-regulated LH and PRL gene expression and spontaneous release.
J Mol Endocrinol 1995 Feb
PMID:Sequence analysis of the turkey LH beta subunit and its regulation by gonadotrophin-releasing hormone and prolactin in cultured pituitary cells. 777 35

Subcutaneous administration of CoCl2, a well recognized inhibitor of hepatic heme synthesis, to rats results in the functional stimulation of total (holo- + apo) tryptophan 2,3 dioxygenase (TDO), a hemoprotein and the key rate-limiting enzyme in the oxidative metabolism of tryptophan to formylkynurenine. Because basal holo-TDO activity is not altered, TDO stimulation appears to be entirely due to CoCl2-mediated increase of its apoprotein. This apoTDO increase was blocked by conventional inhibitors of protein synthesis (actinomycin D, cycloheximide), thereby revealing that such CoCL2-mediated apoprotein increase truly reflected TDO induction. To determine whether the CoCl2-mediated TDO induction involved the action of its natural physiological inducers (glucocorticoids) or was due to direct CoCl2-regulation of the TDO gene, rats were adrenalectomized before CoCl2 administration. In adrenalectomized rats, CoCl2 failed to induce TDO, but induction was completely restored on administration of the glucocorticoid hydrocortisone, but not of adrenaline. These findings reveal that CoCl2-mediated TDO induction is indirect and entails glucocorticoid participation. In addition, because CoCl2 lowered the % heme saturation of TDO [= 100(holo TDO activity/total (apo+holo) TDO activity] largely by increasing the apoTDO protein levels rather than by affecting the basal holo-TDO levels (as expected from its inhibition of heme synthesis), these findings question the widely accepted use of the relative intrahepatic % heme saturation of TDO as a reporter of the hepatic "free" heme pool.
Cell Mol Biol (Noisy-le-grand) 1994 Nov
PMID:Cobaltous chloride-mediated induction of rat hepatic tryptophan 2,3-dioxygenase: implications for the use of the enzyme to probe the hepatic free heme pool. 784 55

We isolated a 38 kDa ssDNA-binding protein from the unicellular cyanobacterium Synechococcus sp. strain PCC 6301 and determined its N-terminal amino acid sequence. A genomic clone encoding the 38 kDa protein was isolated by using a degenerate oligonucleotide probe based on the amino acid sequence. The nucleotide sequence and predicted amino acid sequence revealed that the 38 kDa protein is 306 amino acids long and homologous to the nuclear-encoded 370 amino acid chloroplast ribosomal protein CS1 of spinach (48% identity), therefore identifying it as ribosomal protein (r-protein) S1. Cyanobacterial and chloroplast S1 proteins differ in size from Escherichia coli r-protein S1 (557 amino acids). This provides an additional evidence that cyanobacteria are closely related to chloroplasts. The Synechococcus gene rps1 encoding S1 is located 1.1 kb downstream from psbB, which encodes the photosystem II P680 chlorophyll a apoprotein. An open reading frame encoding a potential protein of 168 amino acids is present between psbB and rps1 and its deduced amino acid sequence is similar to that of E. coli hypothetical 17.2 kDa protein. Northern blot analysis showed that rps1 is transcribed as a monocistronic mRNA.
Mol Gen Genet 1995 Jan 20
PMID:Structure and expression of the gene encoding ribosomal protein S1 from the cyanobacterium Synechococcus sp. strain PCC 6301: striking sequence similarity to the chloroplast ribosomal protein CS1. 786 84

Steady-state mRNA levels for thylakoid proteins were analysed in spinach cotyledons under diurnally changing light conditions. Most fluctuate considerably throughout the day, while the levels of others show only low amplitude or no oscillation. Levels of mRNAs coding for proteins that belong to the same multiprotein complex generally oscillate in parallel and exhibit maxima that are specific for that complex: mRNAs for photosystem I proteins appear prior to those for photosystem II polypeptides and these again prior to mRNAs for the three polypeptides constituting the oxygen-evolving complex. For the mRNAs that change with high amplitudes (e.g. those for LHCP or the 20 kDa apoprotein of the CP24 complex) oscillations have also been found under constant conditions, indicating that a circadian oscillator is involved. Transgenic tobacco seedlings harbouring chimeric GUS gene fusions with 5'-flanking sequences from the spinach genes Lhcb, PsaF and AtpD (encoding a light-harvesting chlorophyll a/b apoprotein of photosystem II, subunit 3 of photosystem I and subunit delta of the plastid ATP synthase, respectively) confirm that the differences in the amplitudes as well as the timepoints of maximum mRNA accumulation are perceived via cis-regulatory elements upstream of the respective ATG codons.
Mol Gen Genet 1995 Feb 20
PMID:The steady-state mRNA levels for thylakoid proteins exhibit coordinate diurnal regulation. 789 61

Polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) was used to identify the common apoprotein E (apo E) isoform genotypes. DNA from the target sequence on apo E was amplified by PCR from peripheral blood genomic DNA. Non-radiolabelled natural PCR products were electrophoresed on a polyacrylamide gradient gel and automatically silver-stained. Bands compatible with each of the three common apo E isoforms were obtained. This method, which does not require restriction enzymes or DNA purification, is a rapid and useful means of detecting the apo E isoform genotype.
Mol Cell Probes 1994 Feb
PMID:Rapid identification of the common apo E isoform genotype using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). 791 6

Earlier studies showed that in Fundulus heteroclitus liver, the content of microsomal cytochrome P4501A (CYP1A) protein induced by beta-naphthoflavone is elevated for weeks after its induction, whereas the content of the induced CYP1A mRNA peaks and declines rapidly (2-4 days). This finding suggests an unusually long half-life for teleost CYP1A. We examined directly the half-live of hepatic microsomal CYP1A protein and heme moieties in F. heteroclitus, by measuring the incorporation and disposition of [3H]-leucine and [14C]-5-aminolevulinic acid (ALA) in fish that had been treated with the CYP1A inducer beta-naphthoflavone prior to administration of label. Incorporation of [3H]-leucine into trichlororacetic acid-precipitable (total) microsomal protein and into immunoprecipitated CYP1A protein peaked between 1.5 to 4 hours. Incorporation of [14C]-ALA into total microsomal (heme) protein peaked at 24 hours, and into the heme of CYP1A at 8 hours. Loss of label from total microsomal protein was biphasic, giving half-lives of 8 and 138 hours for bulk protein, and 66 and 141 hours for heme. CYP1A apoprotein had a half-life of 32 to 39 hours based on isotopic loss and 43 hours calculated from the kinetics of enzyme induction. The apparent half-life of CYP1A heme was approximately 100 hours, which was substantially greater than the protein half-life, in contrast to mammalian P450s, in which half-lives for protein and heme are similar. The distinction in heme half-lives could represent fundamental differences between fish and mammals in P450 heme/protein interactions. The protein half-life is inconsistent with a prolonged stability of CYP1A, yet 30% of the [3H] and 40% of the [14C] seen in CYP1A at the peak of incorporation could still be measured after eight days. Mechanisms other than inherently long-lived protein, perhaps stabilization or enhanced translation of a minor mRNA pool, might contribute to persistence of CYP1A.
Mol Mar Biol Biotechnol 1994 Jun
PMID:Turnover of hepatic microsomal cytochrome P4501A protein and heme in beta-naphthoflavone-induced Fundulus heteroclitus. 792 Oct 47

A cDNA clone encoding the apoprotein of a parsley phytochrome was isolated and classified as parsley PHYA phytochrome, on the basis of a sequence homology comparison with all available phytochrome sequences. Red light pulses led to a phytochrome-dependent down-regulation of PHYA mRNA abundance in etiolated parsley seedlings to a level of 10-20% compared with the dark control. The PHYA mRNA abundance in a parsley cell suspension culture was also down-regulated by light pulses. Transient expression assays in parsley protoplasts showed light regulation of a chimeric pea PHYA promoter uidA-gene construct.
Plant Mol Biol 1994 Oct
PMID:Regulation of phytochrome A mRNA abundance in parsley seedlings and cell-suspension cultures. 794 95

Transcription of nuclear lhc genes has been shown to be under circadian clock control in angiosperms. but many aspects of this regulation have not been elucidated. Unicellular organisms, such as the green alga Chlamydomonas reinhardtii, offer significant advantages for the study of cellular clocks. Therefore, we have asked whether lhc gene expression is regulated by a circadian clock in C. reinhardtii. The mRNA for a photosystem I chlorophyll a/b apoprotein showed a strong diurnal rhythm in cells growing under 12 h/12 h light/dark (LD) cycles; the mRNA accumulated and then declined during the light period reaching very low levels at mid-dark. A similar diurnal pattern was documented for rbcS mRNA. In LD-grown cells shifted to continuous light, the ca. 24 h rhythm of lhca1 mRNA continued for at least 2 cycles. In LD-grown cells shifted to continuous darkness the rhythm of lhca1, but not rbcS2, mRNA also continued, although at lower absolute levels than in LD-grown cells. Also, in the cells shifted to continuous dark, the lhca1 mRNA rhythm persisted in the absence of significant cell division. Pulse-labelling with 32PO4 and sensitivity to actinomycin D demonstrated that control of lhca1 (and rbcS) is mainly transcriptional. However, it was also shown that the half-life of lhca1 mRNA (and rbcS2) is short (1-2 h) and may also vary somewhat during a cycle. We conclude that a cellular, circadian clock regulates lhca1 transcription in C. reinhardtii.
Plant Mol Biol 1994 Oct
PMID:Control of lhc gene transcription by the circadian clock in Chlamydomonas reinhardtii. 794 12

L-Gulono-gamma-lactone oxidase, an enzyme functioning in L-ascorbic acid biosynthesis in higher animals, possesses a covalently-bound FAD as the prosthetic group. Catalytically-active enzyme was expressed in silkworm cells by a recombinant baculovirus encoding rat L-gulono-gamma-lactone oxidase. When recombinant enzyme was expressed under riboflavin-deficient conditions, most of it was found to be the apoprotein, as evidenced by an increase in enzymic activity upon addition of FAD to the assay mixture. Interestingly, the observed enzymic activity is thought to have been provoked by a noncovalent interaction between FAD and the apoprotein, since the covalent attachment of FAD was not demonstrated by a fluorometric gel-scanning experiment.
Biochem Mol Biol Int 1994 May
PMID:Production by a baculovirus expression system of the APO-protein of L-gulono-gamma-lactone oxidase, a flavoenzyme possessing a covalently-bound FAD. 795 Oct 49

Dehydrins are a family of proteins characterised by conserved amino acid motifs, and induced in plants by dehydration or treatment with ABA. An antiserum was raised against a synthetic oligopeptide based on the most highly conserved dehydrin amino acid motif, the lysine-rich (core sequence KIKEK-LPG). This antiserum detected a novel M(r) 40,000 polypeptide and enabled isolation of a corresponding cDNA clone, pPsB61 (B61). The deduced amino acid sequence contained two lysine-rich blocks, however the remainder of the sequenced differed markedly from other pea dehydrins. Surprisingly, the sequence contained a stretch of serine residues, a characteristic common to dehydrins from many plant species but which is missing in pea dehydrin. The expression patterns of B61 mRNA and polypeptide were distinctively different from those of the pea dehydrins during seed development, germination and in young seedlings exposed to dehydration stress or treated with ABA. In particular, dehydration stress led to slightly reduced levels of B61 RNA, and ABA application to young seedlings had no marked effect on its abundance. The M(r) 40,000 polypeptide is thus related to pea dehydrin by the presence of the most highly conserved amino acid sequence motifs, but lacks the characteristic expression pattern of dehydrin. By analogy with heat shock cognate proteins we refer to this protein as a dehydrin cognate.
Plant Mol Biol 1994 Nov
PMID:A dehydrin cognate protein from pea (Pisum sativum L.) with an atypical pattern of expression. 799 96


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