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)

Ethanol has been shown to inhibit N-methyl-D-aspartate (NMDA)-stimulated calcium influx into cerebellar granule cells grown in culture. Because NMDA-mediated responses are modulated by a number of substances, we investigated the effects of several of these agents on ethanol-induced inhibition of calcium flux. Ethanol (50 mM) inhibited NMDA-dependent Ca2+ influx by approximately 50%. The percentage of inhibition remained constant with increasing NMDA concentrations (5-250 microM). Increasing Mg2+ concentrations in the assay medium inhibited NMDA-stimulated calcium influx but the EC50 for Mg2+ was unchanged in the presence of ethanol. Glycine at concentrations of 0.3-100 microM potentiated the effects of NMDA. Glycine at concentrations in excess of 10 microM decreased ethanol-mediated inhibition of NMDA-stimulated calcium influx. D-Serine was shown to have effects similar to those of glycine, whereas L-serine was significantly less active in potentiating NMDA-stimulated activity and reversing the ethanol-induced inhibition of calcium influx. N-Methylglycine and L-leucine were ineffective in potentiating NMDA actions but high concentrations (1 mM) of N-methylglycine attenuated ethanol-induced inhibition, whereas L-leucine (1 mM) had no effect. High concentrations of N-methylglycine were shown to reduce glycine-induced enhancement at the NMDA receptor, whereas L-leucine did not affect the glycine response. Glycine did not affect kainate-stimulated calcium influx and did not alter the small amount of inhibition produced by ethanol in the response of the cells to kainate. The results demonstrate that the in vivo actions of ethanol on the NMDA systems of brain may be dependent on glycine concentrations at these receptor sites.
Mol Pharmacol 1990 Dec
PMID:Glycine site-directed agonists reverse the actions of ethanol at the N-methyl-D-aspartate receptor. 170 Dec 11

Two tomato cDNA libraries were synthesized from poly(A)+ RNAs isolated from unwounded and wounded tomato stems. These cDNA libraries were packaged in lambda gt10 and screened by in situ plaque hybridization with a tomato extensin gene clone (pTom 5.10). Several cDNA clones were identified and isolated from both libraries in this manner and subjected to restriction enzyme digestion. Southern gel blot hybridization, RNA gel blot hybridization, and DNA sequence analyses. From these analyses, the various cDNA clones were found to fall into one of five distinct classes (classes I-V). Class I clones hybridized to a 4.0 kb mRNA which accumulated markedly after wounding and encoded an extensin characterized largely by Ser-(Pro)4-Ser-Pro-Ser-(Pro)4-(Tyr)3-Lys repeats. Class II clones hybridized to a 2.6 kb mRNA which showed no accumulation following wounding and encoded an extensin containing Ser-(Pro)4-Ser-Pro-Ser-(Pro)4-Thr-(Tyr)1-3-Ser repeats. Class III clones hybridized to a 0.6 kb mRNA which greatly accumulated in response to wounding and encoded a glycine-rich protein (GRP) with (Gly)2-6-Tyr-Pro and (Gly)2-6-Arg repeats. Class IV clones contained both class I and class III DNA sequences and consequently hybridized to both the 4.0 kb and the 0.6 kb wound-accumulating mRNAs; these clones encoded a portion of a GRP sequence on one DNA strand and encoded a portion of an extensin sequence on the other DNA strand. Class V clones hybridized to a 2.3 kb mRNA which decreased following wounding and encoded a GRP sequence characterized by (Gly)2-5-Arg repeats.
Plant Mol Biol 1991 Apr
PMID:Tomato extensin and extensin-like cDNAs: structure and expression in response to wounding. 171 16

Continuous overlapping synthetic hexapeptides representing the entire 103 amino acid sequence of the immunodominant B-subunit protein of cholera enterotoxin were used to examine reactivities of a variety of antisera in attempts to detect and define sequence-related (continuous) antigenic regions. The validity of the methods was established by the reactions of polyclonal antisera raised against longer synthetic peptides with appropriate synthetic hexapeptides. An unexpected cross-reaction is attributed to the presence of three identical amino acids (Gln16-Ile17-His18)--although in different order (Gln56-His57-Ile58)--in two parts of the B-subunit chain. Adsorption studies using polyclonal rabbit antisera revealed that, in many instances, denatured B-subunit protein more effectively removed reactivity with hexapeptides than did the native protein. Native holotoxin was more effective than native B-subunit. Sera from human cholera convalescents gave diffuse patterns of reactivity with synthetic hexapeptides--primarily against regions of reactive hexapeptides rather than with clearly defined continuous epitopes. Among many epitopic regions encountered, a strongly reactive tetramer, Ser-Gln-His-Ile (SQHI), was discovered in a highly conserved region, residues 55-58, of the B-subunit amino acid sequence. Adsorption studies revealed that this epitope is apparently exposed on the surface of the native protein. Amino acid substitution revealed the essentiality of Gln and His residues to this epitope. Gly54 was not part of the epitope but substitution of acidic residues Glu and Asp for Gly eliminated reactivity with antibody. The results suggest that continuous epitopes may contribute to the antigenicity of the native toxin protein and may be potentially useful for development of a peptide vaccine.
Mol Immunol 1991 Aug
PMID:Mapping epitopic regions of cholera toxin B-subunit protein. 171 29

A cDNA and a genomic DNA library from soybean (Glycine max L.) were used to identify and sequence two genes coding for the alpha-subunit of the translation elongation factor eEF-1. Within the coding part, the two genes (tefS1 and tefS2) diverge in 80 wobble positions thus yielding an identical protein composed of 447 amino acids. The soybean protein has about 95% similarity with eEF-1 alpha proteins of Arabidopsis thaliana and tomato. Both genes S1 and S2 contain, within the coding part at a site seemingly unique to higher plants, a single short intron of 86 and 116 nucleotides, respectively. The untranslated leader part of both genes is interrupted by a large intron (partially sequenced). Genes S1 and S2 are transcribed in young leaves. cDNA and gene-specific oligonucleotide probes interact with a unique transcript of close to 1.9 kb. Northern hybridization studies using RNAs from dark- and light-grown seedlings show that light sharply increases the level of stable transcripts (1.9 kb). A peak value is measured after about 3 h of illumination, afterwards the transcript concentration drops to about 10% of the peak value. Genes S1 and S2 follow a similar transcription pattern in developing seedling leaves, which is distinct from that of the rbcS genes measured in parallel experiments. According to northern results, S1 transcripts are more abundant in leaves at all measured stages of development than S2 transcripts.
Plant Mol Biol 1991 Sep
PMID:Two genes encoding the soybean translation elongation factor eEF-1 alpha are transcribed in seedling leaves. 171 83

We present the genomic structure of Tam1, a transposable element from Antirrhinum majus. The Tam1 element is 15.2 kb long and includes two genes that are transcribed to produce a 2.4 kb (tnp1) and a 5 kb mRNA (tnp2). These transcripts partially overlap and the exons are scattered over the whole element. Tnp1 encodes a 53 kDa protein as deduced from the cDNA sequence. The 5 kb transcript of tnp2 contains an open reading frame that shares 45% homology with part of the tnpD gene of En/Spm from maize and 48% homology with an open reading frame of the Tgm element from Glycine max. We discuss the possible functions of these genes by analogy with En/Spm. Additionally, a number of flanking sequences of Tam1 insertions were analysed to investigate the sequence specificity of insertion. From these studies we conclude that Tam1 transposes predominantly into AT-rich regions that can be unique as well as repetitive. No specific target sequence of insertion could be found.
Mol Gen Genet 1991 Aug
PMID:The transposable element Tam1 from Antirrhinum majus shows structural homology to the maize transposon En/Spm and has no sequence specificity of insertion. 171 71

We have examined growth, water status and gene expression in dark-grown soybean (Glycine max L. Merr.) seedlings in response to water deficit (low water potentials) during the first days following germination. The genes encoded the plasma membrane proton ATPase and two proteins of 28 kDa and 31 kDa putatively involved in vegetative storage. Water potentials of stems and roots decreased when 2-day-old seedlings were transferred to water-saturated air. Stem growth was inhibited immediately. Root growth continued at control rates for one day and then was totally inhibited when the normal root-stem water potential gradient was reversed. Expression of mRNA for the 28 kDa and 31 kDa proteins, measured independently using specific 3'-end probes, occurred about equally in stems. However, only the mRNA for the 31 kDa protein was detected in roots and at a lower abundance than in stems. Low water potentials increased the mRNA only for the 28 kDa protein in stems and the 31 kDa protein in roots. This differential expression followed the inhibition of stem growth but preceded the inhibition of root growth. The expression of the message for the ATPase, measured using a probe synthesized from a partial oat ATPase clone, was low in stems and roots but there was a 6-fold increase at low water potentials in roots. The increase followed the inhibition of root growth. This appears to be the first instance of regulation of ATPase gene expression in plants and the first demonstration of differential expression of the 28 kDa, 31 kDa, and ATPase messages. The correlation with the differential growth responses of the stems and roots raises the possibility that the differential gene expression could be involved in the growth response to low water potentials.
Plant Mol Biol 1991 Feb
PMID:Low water potentials affect expression of genes encoding vegetative storage proteins and plasma membrane proton ATPase in soybean. 171 98

Insulin-like growth factors (IGFs) together with their binding proteins (BPs) are potential regulators of folliculogenesis in mammalian ovary. To identify the various species of IGFBPs present in the ovary, we have undertaken a comprehensive purification scheme using gel filtration, ligand-affinity chromatography, and several steps of reverse phase HPLC to isolate all of the BPs in pig ovarian follicular fluid. Our effort yielded five distinct IGFBPs, and upon analysis, they were found to correspond to the previously identified human and rat IGFBP-2, -3, -4, -5, and -6. IGFBP-1 was not found in the pig ovarian follicular fluid under our experimental procedure. Of the six known classes of IGFBPs, the complete primary structures of the first five have been determined, but not IGFBP-6. Using amino acid sequence information from a tryptic fragment of pig IGFBP-6 to prepare a probe, cDNA clones encoding rat and human IGFBP-6 have been isolated and characterized. The deduced amino acid sequence revealed that rat IGFBP-6 contains 201 amino acids with a calculated mol wt of 21,461, while the human homolog contains 216 amino acids with a calculated mol wt of 22,847. In addition, a distinctive feature of human and rat IGFBP-6 is that they lack, respectively, two and four of the 18 homologous cysteines that are present in all other five IGFBPs. The missing cysteines in IGFBP-6 resulted in the absence of the invariant Gly-Cys-Gly-Cys-Cys sequence in the amino-terminal region of the molecule. Human IGFBP-6 possesses a single Asn-linked glycosylation site near the carboxyl-terminal, whereas no potential Asn-linked glycosylation sites are present in the rat sequence. A single 1.3-kilobase IGFBP-6 mRNA was detected by Northern analysis in all rat tissues examined, including testis, intestine, adrenal, kidney, stomach, spleen, heart, lung, brain, and liver, indicating that this BP is a ubiquitous protein. The chromosome location of the IGFBP-6 gene in human has been determined using polymerase chain reaction on somatic cell hybrid DNAs of human and hamster, and the results showed that it is located on chromosome 12.
Mol Endocrinol 1991 Jul
PMID:Isolation and molecular cloning of insulin-like growth factor-binding protein-6. 171 83

Monoclonal antibodies against the inhibitory glycine receptor of rat spinal cord were used to identify corresponding receptor polypeptides in goldfish CNS. Both Western blot analysis and quantitative receptor immunoassays revealed crossreacting antigens in goldfish brain membranes. A polypeptide of 46 kDa molecular weight is immunologically related to the 48 kDa alpha subunit of the mammalian receptor. Similarly, a large receptor-associated protein of 93 kDa is present both in goldfish and mammals. Throughout the goldfish CNS, glycine-displaceable [3H]strychnine binding codistributes with the alpha subunit protein as determined immunologically. Glycine receptor contents were highest in goldfish medulla oblongata, medium in optic tectum and mesencephalon, whereas little or no receptor was detected in cerebellum, olfactory bulb, and spinal cord. Immunohistochemistry confirmed that the alpha subunit antigen and the 93 kDa protein were located in the plasma membrane of neurons and concentrated in small clusters found on the soma and dendrites. These data indicate that immunological properties and cellular distribution of glycine receptors are conserved from fish to mammals.
Brain Res Mol Brain Res 1991 Oct
PMID:Conservation of antigenic epitopes of the inhibitory glycine receptor in rodent and goldfish CNS. 172 95

The plasmid pBRD026, which directs expression of the B subunit of the Escherichia coli heat-labile toxin (LTB), was modified so that DNA encoding epitopes could be inserted at the 3' end of the gene. An oligonucleotide linker containing restriction sites for BglII and SpeI was inserted at the SpeI site at the 3' end of the LTB gene to form plasmid pFV1. This linker also encodes the amino acid sequence Gly-Pro-Gly-Pro which we propose acts as a 'hinge' between the LTB and the foreign epitope. Oligonucleotides specifying an epitope from the Bordetella pertussis P.69 outer membrane protein were cloned into pFV1 to form pFV169. The resultant fusion protein (LTB69) was partially purified from the periplasm of E. coli strains in a soluble pentameric form which could bind GM1 gangliosides. Mice immunized intranasally with purified LTB69 produced antibodies against both LTB and the P.69 protein. In addition, ELISPOT assays demonstrated the presence of LTB-specific and P.69-specific antibody-secreting cells in the lungs of immunized mice.
Mol Microbiol 1991 Jun
PMID:Intranasal immunization using the B subunit of the Escherichia coli heat-labile toxin fused to an epitope of the Bordetella pertussis P.69 antigen. 172 57

The Saccharomyces cerevisiae ras-like gene RSR1 is particularly closely related to the mammalian gene Krev-1 (also known as smg21A and rap1A). RSR1 was originally isolated as a multicopy suppressor of a cdc24 mutation, which causes an inability to bud or establish cell polarity. Deletion of RSR1 itself does not affect growth but causes a randomization of bud position. We have now constructed mutant alleles of RSR1 encoding proteins with substitutions of Val for Gly at position 12 (analogous to constitutively activated Ras proteins) or Asn for Lys at position 16 (analogous to a dominant-negative Ras protein). rsr1Val-12 could not restore a normal budding pattern to an rsr1 deletion strain but could suppress a cdc24 mutation when overexpressed. rsr1Asn-16 could randomize the budding pattern of a wild-type strain even in low copy number but was not lethal even in high copy number. These and other results suggest that Rsr1p functions only in bud site selection and not in subsequent events of polarity establishment and bud formation, that this function involves a cycling between GTP-bound and GDP-bound forms of the protein, and that the suppression of cdc24 involves direct interaction between Rsr1p[GTP] and Cdc24p. Functional homology between Rsr1p and Krev-1 p21 was suggested by the observations that expression of the latter protein in yeast cells could both suppress a cdc24 mutation and randomize the budding pattern of wild-type cells. As Krev-1 overexpression can suppress ras-induced transformation of mammalian cells, we looked for effects of RSR1 on the S. cerevisiae Ras pathway. Although no suppression of the activated RAS2Val-19 allele was observed, overexpression of rsr1Val-12 suppressed the lethality of strains lacking RAS gene function, apparently through a direct activation of adenyl cyclase. This interaction of Rsr1p with the effector of Ras in S. cerevisiae suggests that Krev-1 may revert ras-induced transformation of mammalian cells by affecting the interaction of ras p21 with its effector.
Mol Cell Biol 1992 Feb
PMID:RSR1, a ras-like gene homologous to Krev-1 (smg21A/rap1A): role in the development of cell polarity and interactions with the Ras pathway in Saccharomyces cerevisiae. 173 42


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