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G L Long

Publications and source records attributed to G L Long.

At least 73 records · Page 4Linked to original sources
PubMed1986

Evolution and organization of the human protein C gene.

We have isolated overlapping phage genomic clones covering an area of 21 kilobases that encodes the human protein C gene. The gene is at least 11.2 kilobases long and is made up of nine exons and eight introns. Two regions homologous to epidermal growth factor and transforming growth factor are encoded by amino acids 46-91 and 92-136 and are precisely delimited by introns, as is a similar sequence in the genes for coagulation factor IX and tissue plasminogen activator. When homologous amino acids of factor IX and protein C are aligned, the positions of all eight introns correspond precisely, suggesting that these genes are the product of a relatively recent gene duplication. Nevertheless, the two genes are sufficiently distantly related that no nucleic acid homology remains in the intronic regions and that the size of the introns varies dramatically between the two genes. The similarity of the genes for factor IX and protein C suggests that they may be the most closely related members of the serine protease gene family involved in coagulation and fibrinolysis.

Base Sequence↗
PubMed1985

The structure and evolution of a 461 amino acid human protein C precursor and its messenger RNA, based upon the DNA sequence of cloned human liver cDNAs.

Human liver cDNA coding for protein C has been synthesized, cloned and sequenced. The abundance of protein C message is approximately 0.02% of total mRNA. Three overlapping clones contain 1,798 nucleotides of contiguous sequence, which approximates the size of the protein's mRNA, based upon Northern hybridization. The cDNA sequence consists of 73 5'-noncoding bases, coding sequence for a 461 amino acid nascent polypeptide precursor, a TAA termination codon, 296 3'-noncoding bases, and a 38 base polyadenylation segment. The nascent protein consists of a 33 amino acid "signal", a 9 amino acid propeptide, a 155 amino acid "light" chain, a Lys-Arg connecting dipeptide, and a 262 amino acid "heavy" chain. Human protein C and Factor IX and X precursors possess about one third identical amino acids (59% in the gamma-carboxyglutamate domain), including two forty-six amino acid segments homologous to epidermal growth factor. Human protein C also has similar homology with prothrombin in the "leader", gamma-carboxyglutamate and serine protease domains, but lacks the two "kringle" domains found in prothrombin.

Amino Acid Sequence↗
PubMed1985

Localization of the human prealbumin gene to chromosome 18.

A human liver cDNA library was screened using an oligonucleotide probe based on the amino acid sequence of human prealbumin. The cDNA insert of one positive clone was sequenced and found to contain the entire coding sequence of human prealbumin plus untranslated 5' and 3' regions. This cDNA was used to probe DNA from a panel of mouse/human somatic cell hybrids. Only those hybrids containing human chromosome 18 showed the human-specific hybridization pattern, thereby localizing the human prealbumin gene to this chromosome.

Amino Acid Sequence↗
PubMed1984

Complete sequence of the cDNA for human alpha 1-antitrypsin and the gene for the S variant.

A 1434 base pair human liver cDNA coding for the entire alpha 1-antitrypsin protein has been isolated and sequenced. Translation of the coding region into amino acids reveals a precursor molecule which contains a 24 amino acid signal peptide and 394 amino acids present in the mature polypeptide chain. The human gene for the S variant of alpha 1-antitrypsin has also been subcloned and sequenced. The gene is composed of 10226 nucleotide bases and is approximately equimolar for all 4 nucleotides. The gene contains four intervening sequences (introns) and 5' and 3' noncoding regions which are 54 and 79 nucleotides in length, respectively. A 5.3-kilobase intron exists in the 5' noncoding region and contains a 143 amino acid open reading frame, an Alu family sequence, and a pseudo transcription initiation region. No significant differences in base composition are seen between the introns and those regions corresponding to coding regions of the corresponding mRNA (exons). A sequence of 1951 nucleotides flanking the 5' end of the gene has also been determined and contains a "TATA" box sequence (TTAAA-TA) 21 nucleotides upstream from the proposed transcription start site. Comparison of the gene sequence with the cDNA sequence reveals a single base substitution (A----T), which results in a Glu----Val substitution at position 264 in the S variant protein. The position and size of introns, the overall base composition, and the codon preference for the alpha 1-anti-trypsin gene differ from those for the chicken ovalbumin gene even though the two proteins belong to a common protein family, as judged by amino acid sequence homology.

Amino Acid Sequence↗
PubMed1984

Cloning and sequencing of liver cDNA coding for bovine protein C.

cDNA coding for protein C has been cloned from a bovine liver library in plasmid vector pBR322 and its sequence has been determined. Two overlapping clones code for the entire light and heavy chains of the mature protein, as well as a previously unreported connecting dipeptide (Lys-Arg) and a 39-amino acid leader peptide region. Identification and characterization of the clones establishes the liver as a site of protein C biosynthesis. A contiguous coding region reveals that a one-chain precursor protein is made that upon limited proteolysis yields both the mature light and heavy chains. The codon for aspartic acid is found at light chain amino acid position 71, showing that the beta-hydroxyaspartic acid that exists in this position of the mature protein is the result of post-translational modification of an aspartic acid residue. Amino acid sequence homology in the amino-terminal region of the light chain with other vitamin K-dependent coagulation factors is continued into the leader peptide region.

Amino Acid Sequence↗
PubMed1984

Intramolecular hydride transfer of a combined coenzyme-substrate analog by D- and L-lactate dehydrogenases.

The synthesis of 3-[(3-carboxy-3-oxopropyl)aminocarbonyl]pyridine adenine dinucleotide, a new combined analog of NADH and pyruvate with pyruvate covalently attached to the amide nitrogen atom of the dihydronicotinamide ring via an additional methylene group, is described. In the presence of D-lactate dehydrogenase from Limulus polyphemus, from Lactobacillus leichmannii, and L-lactate dehydrogenase from pig skeletal muscle a redox reaction takes place between the pyruvate moiety and the dihydropyridine ring of the analog. This reaction is shown to be intramolecular by competition experiments with pyruvate. Degradation of the reaction products reveals that the carbon-2 atom of the formed lactate side chain exhibits D configuration in each of these cases studied.

Animals↗
PubMed1982

Sequence homology and structural comparison between the chromosomal human alpha 1-antitrypsin and chicken ovalbumin genes.

The human chromosomal alpha 1-antitrypsin gene has been cloned. This gene is approximately 5 kilobase pairs long and contains three intervening sequences in the peptide-coding region. DNA sequences coding for the amino and carboxyl termini of a alpha 1-antitrypsin have been identified. Human alpha 1-antitrypsin and chicken ovalbumin show significant sequences homology and belong to a common protein super-family. Yet the number, position and size of intervening sequences reveal that the two genes are dissimilar.

Animals↗
PubMed1981

Complete amino acid sequence of the catalytic subunit of bovine cardiac muscle cyclic AMP-dependent protein kinase.

The complete amino acid sequence of the 349-residue catalytic subunit of cyclic AMP-dependent protein kinase from bovine cardiac muscle is presented. The sequence of the subunit (Mr 40,580 including phosphate groups at threonine-196 and serine-337) was derived largely by automated Edman degradation of nine fragments generated from the carboxymethylated protein by cleavage of methionyl bonds with cyanogen bromide. These fragments were aligned along the polypeptide chain by analysis of methionine-containing tryptic peptides isolated from protein radiolabeled in vitro by [14C]methyl exchange at methionyl residues. The molecule contains only two cysteinyl residues, at positions 198 and 342. It is relatively polar, containing clusters of cationic residues toward the amino terminus and anionic residues towards the carboxyl terminus. Predictions of secondary structure suggest the presence of three major domains with approximately half of the residues occurring in alpha-helices and 12% in beta-strands.

Amino Acid Sequence↗
PubMed1980

Studies on the active center of D- and L-lactate dehydrogenases using oxamate-diaminohexyl-Sepharose affinity chromatography.

Vertebrate and invertebrate L-lactate dehydrogenases (L-lactate:NAD+ oxidoreductase, EC 1.1.1.27) are effectively bound to oxamate-diaminohexyl-Sepharose, whereas several D-lactate dehydrogenases (D-lactate:NAD+ oxidoreductase, EC 1.1.1.28) do not bind to the same Sepharose. One explanation for our findings is that the enzymes' substrate is oriented in a reversed manner in the active center of the D- and L-lactate dehydrogenases.

Animals↗
PubMed1979

Relationships among spatial skills, communication skills, and field independence in deaf students.

The hypotheses that deaf students would be more field-dependent than hearing students and that their competence in communication skills would be positively related to field-independence were supported for a group of 77 male and 67 female deaf students. Step-wise multiple regression analyses of the data showed that for females spatial skills followed by communication skills were significant predictors of field-independence; for males spatial skills followed by the extent of hearing loss were significant predictors of field-independence. Sex differences found on tests of field-independence and spatial relations were consistent with those obtained from the hearing population. It was suggested that socialization experiences and competence in communication skills may influence development of field-independence in deaf students.

Adult↗