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

A previously undescribed cDNA family was isolated from tobacco challenged with tobacco mosaic virus (TMV). A cDNA library was constructed with mRNA from upper leaves of Xanthi nc tobacco plants that had been inoculated with TMV on the lower leaves 11 days previously. The library was screened differentially with radiolabeled cDNA synthesized with mRNA from upper, uninoculated leaves of either TMV-inoculated or mock-inoculated tobacco plants. The new cDNA family, designated SAR8.2, had at least five expressed members, one or more of which were inducible by TMV inoculation and by salicylic acid treatment. The cDNAs encoded small, highly basic proteins containing N-terminal hydrophobic signal peptides and highly conserved cysteine-rich C-terminal domains. One of the SAR8.2 family members contained a direct repeat of the C-terminal domain in tandem. Hybridization of SAR8.2 cDNA to tobacco genomic DNAs indicated a gene family of 10-12 members.
Mol Plant Microbe Interact
PMID:A new multigene family inducible by tobacco mosaic virus or salicylic acid in tobacco. 147 4

The amdR (intA) regulatory gene of Aspergillus nidulans encodes a 765-amino-acid polypeptide which determines the omega-amino acid induction of at least five structural genes. The AmdR polypeptide contains a potential Zn(II)2Cys6 DNA-binding motif which has been shown to be present in the N-terminal region of a large number of fungal activator proteins. In vitro mutagenesis of the fourth cysteine of this motif abolishes AmdR function as shown by loss of complementation of an amdR- mutation and by the AmdR- phenotype of a mutant gene replacement strain. Studies using constructs in which the proposed AmdR DNA-binding motif is replaced with that from another activator, FacB, shows that induction is independent of DNA-binding specificity and that sequences in the C-terminal region of AmdR are activation domains. Sequencing of several amdR mutant alleles which affect activation and/or induction, together with studies of deletion constructs indicate that changes in the conformation of the protein determines its activity and that this is modulated by inducers.
Mol Microbiol 1992 Oct
PMID:Identification of functional regions of the positively acting regulatory gene amdR from Aspergillus nidulans. 147 91

The T7 polymerase transcription system was used for in vitro synthesis of unmodified versions of the E. coli tRNA mutants that insert asparagine, cysteine, glycine, histidine, and serine. These tRNAs were used to qualitatively explore the role of some anticodon bases and the discriminator nucleotide in the recognition of tRNA by aminoacyl-tRNA synthetases. Coupled with data from earlier studies, these new results essentially complete a survey of all E. coli tRNAs with respect to the involvement of anticodon bases and the discriminator nucleotide in tRNA recognition. It is found that in the vast majority of tRNAs both of these elements are significant components of tRNA identity. This is not universally true, however. Anticodon sequences are unimportant in tRNA(Ser), tRNA(Leu), and tRNA(Ala) while the discriminator base is inconsequential in tRNA(Ser) and tRNA(Thr). The significance of these results for origin-of-life studies is discussed.
J Mol Evol 1992 Nov
PMID:The role of anticodon bases and the discriminator nucleotide in the recognition of some E. coli tRNAs by their aminoacyl-tRNA synthetases. 148 27

We have previously identified cysteine 530 in the human estrogen receptor (ER) as the major site of attachment for covalently binding affinity ligands and have shown that when this cysteine is mutated to alanine (C530A mutant), the affinity ligand [tamoxifen aziridine (TAZ)] can still bind covalently to the ER, presumably by interaction with a different cysteine(s) in the hormone-binding domain (HBD). Using site-directed mutagenesis, we have determined the alternative ligand attachment site and the functional importance of the cysteines (residues 381, 417, 447, and 530) in the HBD of the ER to the hormone-binding and transcriptional responses to estrogens and antiestrogens. Cysteine 530 plus one or more of these other cysteines were mutated to alanines. Analysis of these mutant ERs expressed in Chinese hamster ovary cells provides strong evidence that cysteine 381 is the residue that is preferentially covalently labeled by TAZ in the C530A mutant. Hence, portions of the HBD that are far apart in the linear receptor sequence, namely regions near C381 and C530, are probably closely positioned in the ligand-binding pocket, with the cysteine thiols being 1.1 nm or less apart. The affinity of estradiol binding to receptors was reduced only 2- and 5-fold, respectively, in the double and quadruple Cys to Ala mutants, and estradiol was an effective stimulator of transcription from an estrogen-responsive reporter gene [(ERE)2-TATA-CAT].(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Endocrinol 1992 Dec
PMID:Identification of two cysteines closely positioned in the ligand-binding pocket of the human estrogen receptor: roles in ligand binding and transcriptional activation. 149 95

We isolated a flower-specific cDNA, FST (flower-specific thionin), which encodes a novel thionin from tobacco. Thionins are basic and cysteine (Cys)-rich, low molecular weight proteins found in many plants. They are believed to play a role in plant defense against pathogens. The central domain of the FST protein shares homology with three gamma-thionins. Like other thionin precursors, the FST protein has an N-terminal domain characteristic of a signal peptide and an acidic C-terminal domain. FST mRNA accumulates specifically in developing flowers and its level drops as flowers mature. Transcripts are present in petals, stamens and pistil but are not detectable in sepals. In situ hybridization revealed that FST mRNA is most abundant in the epidermal cells along the adaxial surface of petals, and in the surface cell layers of the carpel and anther walls. If the FST protein indeed has a protective role in flowers, this pattern of spatial distribution of FST mRNA would appear to maximize this effect on the two internal reproductive whorls. A possible biological role for FST is discussed.
Mol Gen Genet 1992 Jul
PMID:A flower-specific cDNA encoding a novel thionin in tobacco. 149 89

The partial amino acid sequences of the gamma chains of the bovine IgG2a(A1) and IgG2a(A2) allotypes were determined. Sequence differences were found in the CH1 domain, the hinge region, and the CH3 domain. The hinge regions displayed only 71.4% similarity and all of the differences were of a radical nature. The A2 hinge has isoleucine instead of serine at 229, histidine for asparagine at 235, proline for histidine at 238, and cysteine instead of proline in position 234; the latter has the potential for forming an additional interheavy chain disulphide bridge. The occurrence of such a bridge could explain the presence of a pepsin fragment consisting of the hinge region and the Fc. A corresponding fragment is not obtained with the A1 allotype. Both allotypes have a shortened hinge region and a truncated CH2 domain. This feature is characteristic of all reported sequences of IgG2 proteins but not IgG1 in cattle and the goat. This structural feature may be important in subclass-specific recognition by Fc gamma receptors in ruminants. A surprising discovery was the occurrence of five substitutions in the CH3 domain of the IgG2a(A2) in comparison with the A1, which are shared with the CH3 of IgG1. These permit the occurrence of isoallotypic determinants and can explain the difficulty encountered in preparing A2-specific antisera during which adsorption with IgG1 is a routine procedure. The primary sequence data we report confirm the presence of major structural differences between the A allotypes of cattle that was suggested by previous work. The sequence of the A1 allotype most closely agrees with the two IgG2 sequences deduced from their nucleotide sequences whereas the sequence differences in the hinge and C-terminal CH3 make IgG2a(A2) unique. The structural differences between allotypes could have major consequences for such biological activities as phagocytosis, transepithelial transport, lymphocyte and complement activation.
Mol Immunol 1992 Sep
PMID:The heterogeneity of bovine IgG2--V. Differences in the primary structure of bovine IgG2 allotypes. 149 1

The complete coding DNA for a Schistosoma mansoni homologue of the epidermal growth factor receptor (SER) was characterized from cDNA clones obtained by homology to the tyrosine kinase domain of erbB. The DNA sequence predicts a 200-kDa translation product that contains a secretory leader, a cysteine-rich extracellular domain, a hydrophobic transmembrane sequence, and an intracellular tyrosine kinase domain. The SER transcript is present in cercariae and adult schistosomes. In addition to SER transcripts, schistosomes produce at least 3 variant transcripts encoding truncated SER products that include the secretory leader and a small portion of the extracellular domain followed by short sequences of unrelated, C-terminal amino acids. Based on these sequences, 2 of the variant mRNAs (class 2 and 5) appear to encode soluble, secreted proteins while one (class 4) encodes an SER variant protein with a hydrophobic C-terminus that may serve as a membrane anchor. Class 2 SER variant transcripts are present at levels comparable to SER transcripts in adult worms but are not detected in cercariae. Class 4 and 5 SER variant transcripts are also found within adult worms but at lower levels. Genomic cloning and characterization demonstrate that the variant SER transcripts arise through alternative splicing of the SER gene.
Mol Biochem Parasitol 1992 Jul
PMID:Alternative splicing of the Schistosoma mansoni gene encoding a homologue of epidermal growth factor receptor. 150 37

Protein P126 (also called P140, P113, SERA, SERP1) is a major parasitophorous vacuole antigen of Plasmodium falciparum. This protein is processed upon merozoite release into 2 fragments of 73 kDa (P73) and 50 kDa (P50), which are found in the culture medium. P73 is composed of 2 polypeptides of 47 and 18 kDa linked by disulfide bridges. In the presence of leupeptin, an inhibitor of serine and cysteine proteases which inhibits merozoite release, a 56-kDa intermediate product (P56) is recovered in the culture medium instead of P50. In order to map these proteolytic fragments on the 126-kDa precursor, we purified them from Plasmodium falciparum culture medium by immunoadsorption, SDS-electrophoresis and Western blotting on PVDF membrane and determined the N termini of P126, P73 (P47 and P18), P50 and P56. Comparison of these sequences with the amino acid sequence deduced from the P126 gene allowed the mapping of the different fragments on the precursor. P47 was at the N-terminal and P18 at the C-terminal end of P126. P56 and P50 had the same N-termini and were located in the middle of P126. This latter result indicates that the proteolysis of P56-P50 occurs at the C-terminus of P56. The peptide bonds cleaved by leupeptin-insensitive activities are Glu-Thr and Gln-Asp; C-terminal sequencing of P50 will be needed to identify the leupeptin-sensitive cleavage site.
Mol Biochem Parasitol 1992 Jul
PMID:Intramolecular mapping of Plasmodium falciparum P126 proteolytic fragments by N-terminal amino acid sequencing. 150 48

The rhombotin (RBTN1 or Ttg-1) gene was first identified at a chromosome translocation in a T-cell acute leukaemia and later used to isolate two related genes (RBTN2 or Ttg-2 and RBTN3). Complete characterization of these genes in man and mouse shows that all three encode cysteine-rich proteins with typical LIM domains. RBTN1 and RBTN3-derived proteins have 98% identity in the LIM domains but are located on separate chromosomes in man and in mouse while RBTN1 and RBTN2, both located on human chromosome 11p but are on separate chromosomes in mouse, are only 48% identical in this part of the protein. The exon organization of RBTN1 and RBTN3 genes are similar, both having an intron, absent from the RBTN2 gene, in the LIM2-encoding region. The remarkable similarity between rbtn-1 and rbtn-3 proteins is parallelled in their expression patterns in mouse development, since both genes show high expression in restricted areas of the brain, but little lymphoid expression. rbtn-2 expression, however, is more ubiquitous. This gene shows a low level of thymus expression but high expression in fetal liver, adult spleen and B-cell lines, consistent with a role in B-cell development. These results suggest multiple cellular targets for the action of these proteins during development.
J Mol Biol 1992 Aug 05
PMID:The rhombotin gene family encode related LIM-domain proteins whose differing expression suggests multiple roles in mouse development. 150 24

A new protein kinase C (PKC)-related cDNA with unique tissue distribution has been isolated and characterized. This cDNA encodes a protein, nPKC theta, which consists of 707 amino acid residues and showed the highest sequence similarity to nPKC delta (67.0% in total). nPKC theta has a zinc-finger-like cysteine-rich sequence (C1 region) and a protein kinase domain sequence (C3 region), both of which are common in all PKC family members. However, nPKC theta lacks a putative Ca2+ binding region (C2 region) that is seen only in the conventional PKC subfamily (cPKC alpha, -beta I, -beta II, and -gamma) but not in the novel PKC subfamily (nPKC delta, -epsilon, -zeta, and -eta). Northern (RNA) blot analyses revealed that the mRNA for nPKC theta is expressed predominantly in skeletal muscle. Furthermore, nPKC theta mRNA is the most abundantly expressed PKC isoform in skeletal muscle among the nine PKC family members. nPKC theta expressed in COS1 cells serves as a phorbol ester receptor. By the use of an antipeptide antibody specific to the D2-D3 region of the nPKC theta sequence, nPKC theta was recognized as a 79-kDa protein upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis in mouse skeletal muscle extract and also in an extract from COS1 cells transfected with an nPKC theta cDNA expression plasmid. Autophosphorylation of immunoprecipitated nPKC theta was observed; it was enhanced by phosphatidylserine and 12-O-tetradecanoylphorbol-13-acetate but attenuated by the addition of Ca2+. These results clearly demonstrate that nPKC theta should be considered a member of the PKC family of proteins that play crucial roles in the signal transduction pathway.
Mol Cell Biol 1992 Sep
PMID:A new member of the protein kinase C family, nPKC theta, predominantly expressed in skeletal muscle. 150 94


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>