Showing papers on "Peptide sequence published in 1985"

Repetitive zinc‐binding domains in the protein transcription factor IIIA from Xenopus oocytes.

Abstract: The 7S particle of Xenopus laevis oocytes contains 5S RNA and a 40-K protein which is required for 5S RNA transcription in vitro. Proteolytic digestion of the protein in the particle yields periodic intermediates spaced at 3-K intervals and a limit digest containing 3-K fragments. The native particle is shown to contain 7-11 zinc atoms. These data suggest that the protein contains repetitive zinc-binding domains. Analysis of the amino acid sequence reveals nine tandem similar units, each consisting of approximately 30 residues and containing two invariant pairs of cysteines and histidines, the most common ligands for zinc. The linear arrangement of these repeated, independently folding domains, each centred on a zinc ion, comprises the major part of the protein. Such a structure explains how this small protein can bind to the long internal control region of the 5S RNA gene, and stay bound during the passage of an RNA polymerase molecule.

Various rat adult tissues express only one major mRNA species from the glyceraldehyde-3-phosphate-dehydrogenase multigenic family

Abstract: We have isolated and sequenced a full-length cDNA clone encoding rat glyceraldehyde-3-phosphate-dehydrogenase (GAPDH, E.C.1.2.1.12). The entire mRNA is 1269 nucleotides long exclusive of poly(A) and contains respectively 71 and 196 bases of 5' and 3' non-coding regions. Primer extension as well as S1 nuclease protection experiments clearly established that a single (or at least a highly prominent) GAPDH mRNA species is expressed in all rat tissues examined. This sequence allowed the determination of the hitherto unknown primary structure of rat GAPDH which is 333 aminoacids long. Comparison between GAPDH sequences from rat, man and chicken revealed a high degree of sequence conservation at both nucleotide and protein levels.

Primary structure and expression of a functional human glucocorticoid receptor cDNA

Abstract: Identification of complementary DNAs encoding the human glucocorticoid receptor predicts two protein forms, of 777 (alpha) and 742 (beta) amino acids, which differ at their carboxy termini. The proteins contain a cysteine/lysine/arginine-rich region which may define the DNA-binding domain. Pure radiolabelled glucocorticoid receptor, synthesized in vitro, is immunoreactive and possesses intrinsic steroid-binding activity characteristic of the native glucocorticoid receptor.

General method for the rapid solid-phase synthesis of large numbers of peptides: specificity of antigen-antibody interaction at the level of individual amino acids

Abstract: A novel yet simple method is described that facilitates the synthesis of large numbers of peptides to the extent that the synthesis process need no longer be the limiting factor in many studies involving peptides. By using the methods described, 10-20 mg of 248 different 13-residue peptides representing single amino acid variants of a segment of the hemagglutinin protein (HA1) have been prepared and characterized in less than 4 weeks. Through examination of the binding of these analogs to monoclonal antibodies raised against residues 75-110 of HA1, it was found that a single amino acid, aspartic acid at position 101, is of unique importance to the interaction. Two other residues, aspartic acid-104 and alanine-106, were found to play a lesser but significant role in the binding interaction. Other single positional residue variations appear to be of little or no importance.

Human transforming growth factor-beta complementary DNA sequence and expression in normal and transformed cells.

Abstract: The partial amino-acid sequence of purified human transforming growth factor-beta (TGF-beta) was used to identify a series of cDNA clones encoding the protein. The cDNA sequence indicates that the 112-amino acid monomeric form of the natural TGF-beta homodimer is derived proteolytically from a much longer precursor polypeptide which may be secreted. TGF-beta messenger RNA is synthesized in various normal and transformed cells.

Cloning, sequence and expression of two distinct human interleukin-1 complementary DNAs

Abstract: Two distinct but distantly related complementary DNAs encoding proteins sharing human interleukin-1 (IL-1) activity (termed IL-1 alpha and IL-1 beta), were isolated from a macrophage cDNA library. The primary translation products of the genes are 271 and 269 amino acids long, although expression in Escherichia coli of the carboxy-terminal 159 and 153 amino acids produces IL-1 biological activity.

Sequence and structure of a human glucose transporter

Abstract: The amino acid sequence of the glucose transport protein from human HepG2 hepatoma cells was deduced from analysis of a complementary DNA clone. Structural analysis of the purified human erythrocyte glucose transporter by fast atom bombardment mapping and gas phase Edman degradation confirmed the identity of the clone and demonstrated that the HepG2 and erythrocyte transporters are highly homologous and may be identical. The protein lacks a cleavable amino-terminal signal sequence. Analysis of the primary structure suggests the presence of 12 membrane-spanning domains. Several of these may form amphipathic alpha helices and contain abundant hydroxyl and amide side chains that could participate in glucose binding or line a transmembrane pore through which the sugar moves. The amino terminus, carboxyl terminus, and a highly hydrophilic domain in the center of the protein are all predicted to lie on the cytoplasmic face. Messenger RNA species homologous to HepG2 glucose transporter messenger RNA were detected in K562 leukemic cells, HT29 colon adenocarcinoma cells, and human kidney tissue.

Induction of hepatitis A virus-neutralizing antibody by a virus-specific synthetic peptide.

Abstract: Comparative surface feature analyses of the VP1 sequences of hepatitis A virus (HAV) and poliovirus type 1 allowed an alignment of the two sequences and an identification of probable HAV neutralization antigenic sites. A synthetic peptide containing the HAV-specific amino acid sequence of one of these sites induced anti-HAV-neutralizing antibodies. It is concluded that a structural homology exists between the two viruses, despite minimal primary sequence conservation.

Cloning and expression of the human erythropoietin gene.

Abstract: The human erythropoietin gene has been isolated from a genomic phage library by using mixed 20-mer and 17-mer oligonucleotide probes. The entire coding region of the gene is contained in a 5.4-kilobase HindIII-BamHI fragment. The gene contains four intervening sequences (1562 base pairs) and five exons (582 base pairs). It encodes a 27-amino acid signal peptide and a 166-amino acid mature protein with a calculated Mr of 18,399. The erythropoietin gene, when introduced into Chinese hamster ovary cells, produces erythropoietin that is biologically active in vitro and in vivo.

Amplification of a novel v-erbB-related gene in a human mammary carcinoma

Abstract: The cellular gene encoding the receptor for epidermal growth factor (EGF) has considerable homology to the oncogene of avian erythroblastosis virus. In a human mammary carcinoma, a DNA sequence was identified that is related to v-erbB but amplified in a manner that appeared to distinguish it from the gene for the EGF receptor. Molecular cloning of this DNA segment and nucleotide sequence analysis revealed the presence of two putative exons in a DNA segment whose predicted amino acid sequence was closely related to, but different from, the corresponding sequence of the erbB/EGF receptor. Moreover, this DNA segment identified a 5-kilobase transcript distinct from the transcripts of the EGF receptor gene. Thus, a new member of the tyrosine kinase proto-oncogene family has been identified on the basis of its amplification in a human mammary carcinoma.

Amino-acid sequence of a Ca2+ + Mg2+-dependent ATPase from rabbit muscle sarcoplasmic reticulum, deduced from its complementary DNA sequence.

Abstract: We have cloned and sequenced complementary DNA encoding a Ca2+-ATPase of rabbit muscle sarcoplasmic reticulum. We propose a model of the protein which has 3 cytoplasmic domains joined to a set of 10 transmembrane helices by a narrow, penta-helical stalk. In this model. ATP bound to one cytoplasmic domain would phosphorylate an aspartate in an adjoining cytoplasmic domain, inducing translocation of Ca2+ from binding sites on the stalk.

Identification of three classes of cytosolic glutathione transferase common to several mammalian species: correlation between structural data and enzymatic properties.

Abstract: The major isoenzymes of cytosolic glutathione transferase (EC 2.5.1.18) from rat, mouse, and man are shown to share structural and catalytic properties that can be used for species-independent classification. Rat, mouse, and human isoenzymes were grouped with respect to amino-terminal amino acid sequences, after correlation of seven structures analyzed in the present investigation with structures determined earlier. The isoenzymes were also characterized by substrate specificities and sensitivities to inhibitors, and the data were subjected to pattern recognition analysis. In addition, the various isoenzymes were tested for cross-reactivity by immunoprecipitation with antibodies raised against rat and human transferases. The different types of data were clearly correlated and afforded an unambiguous division of the isoenzymes into three classes named alpha, mu, and pi. Each of the three mammalian species studied contains at least one isoenzyme of each class. It is suggested that the similarities of the isoenzymes in a class reflect evolutionary relationships and that the classification applies generally.

Amino acid homology between the encephalitogenic site of myelin basic protein and virus: mechanism for autoimmunity

Abstract: Amino acid sequence homology was found between viral and host encephalitogenic protein. Immune responses were then generated in rabbits by using the viral peptide that cross-reacts with the self protein. Mononuclear cell infiltration was observed in the central nervous systems of animals immunized with the viral peptide. Myelin basic protein (MBP) is a host protein whose encephalitogenic site of ten amino acids induces experimental allergic encephalomyelitis. By computer analysis, hepatitis B virus polymerase (HBVP) was found to share six consecutive amino acids with the encephalitogenic site of rabbit MBP. Rabbits given injections of a selected eight- or ten-amino acid peptide from HBVP made antibody that reacted with the predetermined sequences of HBVP and also with native MBP. Peripheral blood mononuclear cells from the immunized rabbits proliferated when incubated with either MBP or HBVP. Central nervous system tissue taken from these rabbits had a histologic picture reminiscent of experimental allergic encephalomyelitis. Thus, viral infection may trigger the production of antibodies and mononuclear cells that cross-react with self proteins by a mechanism termed molecular mimicry. Tissue injury from the resultant autoallergic event can take place in the absence of the infectious virus that initiated the immune response.

Conserved features of eukaryotic hsp70 genes revealed by comparison with the nucleotide sequence of human hsp70.

Abstract: We have determined the nucleotide sequence of the human hsp70 gene and 5' flanking region. The hsp70 gene is transcribed as an uninterrupted primary transcript of 2440 nucleotides composed of a 5' noncoding leader sequence of 212 nucleotides, a 3' noncoding region of 242 nucleotides, and a continuous open reading frame of 1986 nucleotides that encodes a protein with predicted molecular mass of 69,800 daltons. Upstream of the 5' terminus are the canonical TATAAA box, the sequence ATTGG that corresponds in the inverted orientation to the CCAAT motif, and the dyad sequence CTGGAAT/ATTCCCG that shares homology in 12 of 14 positions with the consensus transcription regulatory sequence common to Drosophila heat shock genes. Comparison of the predicted amino acid sequences of human hsp70 with the published sequences of Drosophila hsp70 and Escherichia coli dnaK reveals that human hsp70 is 73% identical to Drosophila hsp70 and 47% identical to E. coli dnaK. Surprisingly, the nucleotide sequences of the human and Drosophila genes are 72% identical and human and E. coli genes are 50% identical, which is more highly conserved than necessary given the degeneracy of the genetic code. The lack of accumulated silent nucleotide substitutions leads us to propose that there may be additional information in the nucleotide sequence of the hsp70 gene or the corresponding mRNA that precludes the maximum divergence allowed in the silent codon positions.

The LDL Receptor Gene: A Mosaic of Exons Shared with Different Proteins

Abstract: The multifunctional nature of coated pit receptors predicts that these proteins will contain multiple domains. To establish the genetic basis for these domains (LDL) receptor. This gene is more than 45 kilobases in length and contains 18 exons, most of which correlate with functional domains previously defined at the protein level. Thirteen of the 18 exons encode protein sequences that are homologous to sequences in other proteins: five of these exons encode a sequence similar to one in the C9 component of complement; three exons encode a sequence similar to a repeat sequence in the precursor for epidermal growth factor (EGF) and in three proteins of the blood clotting system (factor IX, factor X, and protein C); and five other exons encode nonrepeated sequences that are shared only with the EGF precursor. The LDL receptor appears to be a mosaic protein built up of exons shared with different proteins, and it therefore belongs to several supergene families.

Complementary DNA Sequences of Ovarian Follicular Fluid Inhibin Show Precursor Structure and Homology With Transforming Growth Factor-Beta

Abstract: Inhibin, a specific and potent polypeptide inhibitor of the secretion of follicle-stimulating hormone (FSH)1, of gonadal origin and thus a potential contraceptive, may constitute a missing link in the mechanism controlling the differential secretion of the pituitary gonadotropins. Inhibin-like bioactivity has been reported in various fluids and extracts of testis2–5 and in ovarian follicular fluid6–10. Although there have been several attempts to purify inhibin from seminal plasma11–13, purification from follicular fluid has been more successful (refs 14–16; for review see ref. 17). We have previously isolated two forms (A and B) of inhibin from porcine follicular fluid14. Each form comprised two dissimilar subunits of relative molecular mass (Mr) 18,000 (18K, referred to here as the α-subunit) and 14K (the β-subunit), crosslinked by one or more disulphide bridges(s). Forms A and B differ in the N-terminal sequence of their 14K subunit. Preliminary structural characterization of porcine15 and bovine16 ovarian inhibins shows that they have similar properties. Here, we have used the N-terminal amino-acid sequence data on the subunits of each inhibin to identify cloned complementary DNAs encoding the biosynthetic precursors and report that inhibins are the product of a gene family that also includes transforming growth factor-β (TGF-β) and whose structural organization is similar to that of pituitary and placental glycoprotein hormones.

Amino-acid sequence of the catalytic subunit of the (Na + + K + )ATPase deduced from a complementary DNA

Abstract: We have isolated and characterized a complementary DNA for the catalytic subunit of the sheep kidney sodium / potassium-dependent ATPase The 1,016-amino-acid protein seems to have eight transmembrane domains The apparent ouabain binding site is located at the extracellular junction of two transmembrane domains and is linked to the phosphorylation site by a 60-amino-acid conserved sequence that may be a major channel for energy transduction

Primary structure of bovine pituitary basic fibroblast growth factor (FGF) and comparison with the amino-terminal sequence of bovine brain acidic FGF.

Abstract: The two major mitogenic polypeptides for endothelial cells have been purified to homogeneity The complete primary structure of bovine pituitary basic fibroblast growth factor (FGF) and the amino-terminal amino acid sequence of bovine brain acidic FGF have been established by gas-phase sequence analyses Homogeneous preparations of these polypeptides are potent mitogens (basic FGF, ED50 approximately equal to 60 pg/ml; acidic FGF ED50 approximately equal to 6000 pg/ml) for many diverse cell types including capillary endothelial cells, vascular smooth muscle cells, and adrenocortical and granulosa cells; in vivo, basic FGF is a powerful angiogenic agent in the chick chorioallantoic membrane assay The available protein sequence data demonstrate the existence of significant structural homology between the two polypeptides

Primary structure of human fibronectin: differential splicing may generate at least 10 polypeptides from a single gene.

Abstract: Cellular and plasma fibronectins are heterodimers consisting of similar but not identical polypeptides. The differences between fibronectin subunits are due in part to the variability of internal primary sequences. This results from alternative splicing in at least two regions (ED and IIICS) of the pre-mRNA. The complete primary structure of human fibronectin, including most of the internal variations, has been determined by sequencing a series of overlapping cDNA clones. In total, they covered 7692 nucleotides and represented the mRNA sequence coding from the amino terminus of the mature protein to the poly(A) tail. The deduced amino acid sequence of fibronectin has been analysed in terms of the arrangement of internal homologies and the different binding domains.

Molecular cloning of the complementary dna for human tumor necrosis factor

Abstract: Tumor necrosis factor (TNF) is a soluble protein that causes damage to tumor cells but has no effect on normal cells. Human TNF was purified to apparent homogeneity as a 17.3-kilodalton protein from HL-60 leukemia cells and showed cytotoxic and cytostatic activities against various human tumor cell lines. The amino acid sequence was determined for the amino terminal end of the purified protein, and oligodeoxyribonucleotide probes were synthesized on the basis of this sequence. Complementary DNA (cDNA) encoding human TNF was cloned from induced HL-60 messenger RNA and was confirmed by hybrid-selection assay, direct expression in COS-7 cells, and nucleotide sequence analysis. The human TNF cDNA is 1585 base pairs in length and encodes a protein of 233 amino acids. The mature protein begins at residue 77, leaving a long leader sequence of 76 amino acids. Expression of high levels of human TNF in Escherichia coli was accomplished under control of the bacteriophage lambda PL promoter and gene N ribosome binding site.

Sequence of protein disulphide isomerase and implications of its relationship to thioredoxin

Abstract: The formation of disulphide bonds is essential to the structure and function of proteins. These bonds rapidly form either cotranslationally or immediately post-translationally in the lumen of the endoplasmic reticulum. Native disulphide pairing for such proteins has been achieved in vitro; however, the rates of reassembly are slow and the conditions non-physiological. To account for these observations, Anfinsen et al. proposed that a 'disulphide interchange protein' was the in vivo catalyst of disulphide bond rearrangement. Other groups discovered an activity with similar characteristics that catalysed the reductive cleavage of insulin and may be associated with insulin degradation, although this result has been disputed. The enzyme involved, protein disulphide isomerase (PDI; EC 5.3.4.1), may be the in vivo catalyst of disulphide bond formation. Here we describe the sequence of cloned rat liver PDI complementary DNA which predicts a protein with two distinct regions homologous with Escherichia coli thioredoxin, a known cofactor in oxidation-reduction reactions. Each of these regions contains the presumed active site sequence Trp-Cys-Gly-His-Cys-Lys, suggesting that PDI, similar in action to thioredoxin, catalyses disulphide bond interchange via an internal disulphide-sulphydryl interchange. The cDNA predicts a signal peptide consistent with the view that PDI is a luminal endoplasmic reticulum protein. PDI messenger RNA, although ubiquitous, is more highly concentrated in secretory cells.

The effect of Arg-Gly-Asp-containing peptides on fibrinogen and von Willebrand factor binding to platelets.

Abstract: The Arg-Gly-Asp sequence resides in the cell attachment region of fibronectin. Arg-Gly-Asp-containing peptides support fibroblast attachment, inhibit fibroblast adhesion to fibronectin, and inhibit fibronectin binding to thrombin-stimulated platelets. In view of the similarities between the binding of fibronectin, fibrinogen, and von Willebrand factor to stimulated platelets, we have examined the effects of Arg-Gly-Asp-containing peptides on the interaction of these latter two adhesive proteins with platelets. Gly-Arg-Gly-Asp-Ser-Pro was used as a prototype peptide, and this hexapeptide inhibited fibrinogen binding to ADP and thrombin-stimulated platelets in the 10-200 microM range. The inhibition exceeded 90% at high concentrations of peptide and was observed in the presence of either calcium or magnesium. Platelet aggregation was also inhibited by the peptide in this dose range. The hexapeptide inhibited fibrinogen binding to platelets with receptors fixed in an exposed state, indicating direct interference with the ligand-platelet interaction. The peptide was 1/2 to 1/3rd as potent in inhibiting fibrinogen as fibronectin binding to platelets, but fibrinogen and von Willebrand factor binding were inhibited to an identical extent. Conservative amino acid substitutions for the arginine, glycine, or aspartic acid markedly reduced inhibitory activity and the Asp-Gly-Arg sequence was inactive. These results indicate that Arg-Gly-Asp-containing peptides can inhibit the binding of the three adhesive proteins to stimulated platelets, establishing a basic common feature between the interaction of these molecules with platelets.

Structure of the GDP domain of EF-Tu and location of the amino acids homologous to ras oncogene proteins

Abstract: A 2.7 angstrom resolution x-ray diffraction analysis of a trypsin-modified form of the Escherichia coli elongation factor Tu reveals that the GDP-binding domain has a structure similar to that of other nucleotide-binding proteins. The GDP ligand is located at the COOH-terminal end of the beta sheet and is linked to the protein via a Mg2+ ion salt bridge. The location of the guanine ring is unusual; the purine ring is located on the outer edge of the domain, not deep within a hydrophobic pocket. The amino acids from Pro10 to Arg44 and from Gly59 to Glu190 have been assigned to the electron density with computer graphic techniques, and the resulting model is consistent with all known biochemical data. An analysis of the structure reveals that four regions of the amino acid sequence that are homologous with the family of ras oncogene proteins, termed p21, are located in the vicinity of the GDP-binding site, and most of the invariant amino acids shared by the proteins interact directly with the GDP ligand.

Mouse-human chimaeric immunoglobulin heavy chain, and chimaeric DNA encoding it

Abstract: A mouse-human chimaeric immunoglobulin heavy chain comprising (a) the amino acid sequence of a mouse immunoglobulin heavy chain variable region and (b) the amino acid sequence of a human immunoglobulin heavy chain constant region and reacting specifically with human common acute lymphocytic leukemia antigen and a chimaeric DNA fragment which encodes the amino acid sequence of the above mouse-human chimaeric immunoglobulin heavy chain.

Primary structures of three human neutrophil defensins.

Abstract: The primary structures of three human neutrophil antimicrobial peptides (HNP) were determined. The peptides, HNP-1, HNP-2, and HNP-3, which we have termed defensins, were rich in cystine, arginine, and aromatic residues, but were devoid of free sulfhydryl groups and carbohydrate moieties. They were 29-30 residues in length and identical in sequence in all but their amino terminal residues. The defensins were homologous in sequence to peptides of similar size and biological activity previously purified from rabbit polymorphonuclear leukocytes, but unrelated to other neutrophil proteins of known sequence. 11 amino acid residues of the human defensins, including all six cysteinyl residues, were invariantly conserved in the six rabbit members of this multigene peptide family. That similarly structured antimicrobial peptides are present in both rabbit and human leukocytes supports their purported role as cidal agents in phagocyte-mediated host defense.

Human Lymphotoxin and tumor necrosis factor genes: structure, homology and chromosomal localization

Abstract: Human Tumor Necrosis Factor and Lymphotoxin are cytotoxic proteins which have similar biological activities and share 30 percent amino acid homology. The single copy genes which encode these proteins share several structural features: each gene is approximately three kilobase pairs in length and is interrupted by three introns. In addition, these genes are closely linked and have been mapped to human chromosome 6. However, only the last exons of both genes, which code for more than 80 percent of each secreted protein, are significantly homologous (56 percent).