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H Sinohara

Publications and source records attributed to H Sinohara.

At least 37 records · Page 2Linked to original sources
PubMed1996

Cloning and sequencing of cDNAs encoding plasma alpha-macroglobulin and murinoglobulin from guinea pig: implications for molecular evolution of alpha-macroglobulin family.

Several clones encoding plasma alpha-macroglobulin and murinoglobulin were isolated from guinea pig liver cDNA library and sequenced. The clones for alpha-macroglobulin contained overlapping sequences which together spanned a stretch of 4,546 nucleotides with one open reading frame coding for 1,476 amino acid residues. The clones for murinoglobulin contained overlapping sequences which together spanned a stretch of 4,578 nucleotides with one open reading frame coding for 1,464 amino acid residues. The phylogenetic analyses of 11 proteins of the alpha-macroglobulin family revealed that the mammalian tetrameric alpha-macroglobulins consist of two main branches: alpha M-1 subfamily (rat alpha 1- and mouse alpha-macroglobulins) and alpha M-2 subfamily (human alpha 2-, rat alpha 2-, and guinea pig alpha-macroglobulins). This dichotomy is in good accordance with their immunological, chemical, and physicochemical properties, and indicates that guinea pig alpha-macroglobulin is orthologous to human and rat alpha 2-macroglobulins but paralogous to rat alpha 1- and mouse alpha-macroglobulins. The divergence of the two subfamilies was a phylogenetically ancient event which occurred around the separation of metatherians and eutherians. The genes of the two subfamilies have been maintained in the rat, but either one became extinct in the mouse, guinea pig, or human. The tree also shows that guinea pig murinoglobulin forms one clade with mouse and rat murinoglobulins (alpha 1-inhibitor 3) prior to joining the alpha M-2 lineage, and suggests that murinoglobulin is not a primitive form of tetrameric alpha-macroglobulin, but rather has evolved under selective pressure which is different from that of the tetrameric paralogues.

Amino Acid Sequence↗
PubMed1996

Catalytic cleavage of vasopressin by human Bence Jones proteins at the arginylglycinamide bond.

Bence Jones proteins were capable of hydrolyzing a peptide bond between arginine-8 and the C-terminal glycinamide of vasopressin. This peptidolytic activity obeyed typical Michaelis-Menten kinetics and exhibited optimal activity at pH 8.2 and Km of 0.6-1.9 mM. The catalytic efficiency, kcat/Km, was calculated to be 0.8 to 5.8 min(-1)M(-1). The Bence Jones proteins displayed turnover, an essential feature of enzymes. These results suggest that slow proteolysis, especially in the renal tubules which are 'saturated' with Bence Jones proteins, may have a pathophysiological significance for various nephropathies often associated with multiple myeloma with Bence Jones proteinuria.

Arginine↗
PubMed1995

Molecular cloning and sequence analysis of cDNA encoding plasma alpha-1-antiproteinase from Syrian hamster: implications for the evolution of Rodentia.

Complementary DNA clones encoding plasma alpha-1-antiproteinase (also called alpha-1-antitrypsin or alpha-1-proteinase inhibitor) were isolated from Syrian hamster liver cDNA library and sequenced. The deduced amino acid sequence of putative reactive site (P3-P'3) was Ile-Pro-Met-Ser-Val-Pro, characteristic of alpha-1-antiproteinase of orthodox type (Suzuki, Y. et al. (1991) J. Biol. Chem. 266, 928-932). A molecular phylogenetic tree of all known orthologous proteins was constructed based on the synonymous substitution rate. The result shows that the hamster has branched off first before the divergence among mice, rats, and gerbils, and that the rabbit is the closest relative of the guinea pig which is separated from the rodents. Although this tree differs largely from the classical phylogeny based on the morphology (hamsters and gerbils belong to the same family, Cricetidae, and the guinea pig belongs to the order Rodentia), it lends support to recent concepts that the hamster and guinea pig differ, in a number of biochemical features, not only from each other but also from mice and rats, and that the guinea pig may belong to an order distinct from Rodentia.

Amino Acid Sequence↗
PubMed1995

Rabbit alpha-1-antiproteinase E: a novel recombinant serpin which does not inhibit proteinases.

A cDNA coding for the E isoform of alpha-1-antiproteinase (also called alpha-1-antitrypsin or alpha-1-proteinase inhibitor) was isolated by oligonucleotide hybridization following immunochemical screening of the rabbit liver cDNA library. The deduced amino acid sequence of the E isoform showed 96.4% identity in 413 residues of the F and S-1 isoforms of rabbit alpha-1-antiproteinase. The N-terminal half of the amino acid residues of the three isoforms was almost identical, but the putative reactive-site loop structure (P8-P'8) was significantly different in the various forms, the P1 site of the E form being glutamic acid. Interaction of the recombinant E form with the various proteinases was investigated by SDS/PAGE, followed by immunoblot analysis. The recombinant protein and trypsin formed a 62 kDa equimolar complex, which gradually became graded to the 37 kDa fragment through several intermediates. The E form also formed a complex of a similar size with elastase and became degraded to the 31 kDa fragment. Several proteinases which cleaved the E form without forming a detectable complex on SDS/PAGE are chymotrypsin, protease V8, pancreas kallikrein, thermolysin, papain and ficin. Other proteinases, with a stringent substrate specificity, such as thrombin, factor Xa, plasmin, plasma kallikrein and cathepsin G, did not attack the E form. Unlike the F and S-1 forms of rabbit plasma alpha-1-antiproteinase, the recombinant E form did not inhibit the amidolytic and proteolytic activities of trypsin. Neither elastase nor protease V8 was inhibited by the E form. Thus the change in the amino acid residues in the reactive-site loop, probably in the P1 site, is responsible for the loss of inhibitory activity of rabbit alpha-1-antiproteinase E. The novel character of the E form could provide a new insight into the interaction of serpin and proteinases.

Amides↗
PubMed1994

Amidase activity of human Bence Jones proteins.

Bence Jones proteins purified from urine of patients with multiple myeloma were found to be capable of hydrolyzing carbobenzoxy-L-valyl-glycyl-L-arginine p-nitroanilide (Chromozym TRY) and benzoyl-L-arginine p-nitroanilide (BApNA), synthetic chromogenic substrates for trypsin. The amidolytic activity obeyed classic Michaelis-Menten kinetics, exhibiting optimal activity around pH 8.4 and apparent Km of 140-730 microM and 18-27 microM for Chromozym TRY and BApNA, respectively. No activity was detected with intact IgG or Fab fragment, whereas the activity comparable to those of Bence Jones proteins was found with light chain derived from inactive IgG. Several lines of circumstantial evidence indicate that the observed activity was not due to contaminating enzyme.

Amidohydrolases↗
PubMed1994

Small-angle scattering study of alpha 1 inhibitor III from rat blood plasma.

The alpha 1 proteinase inhibitor III from rat blood plasma, homologous to the alpha 2-macroglobulin family of proteins, has been studied in solution using small-angle scattering of X-rays and of neutrons: the radius of gyration, Rg, was found to be 4.5 nm, and the largest distance within the molecule, Dmax = 14 nm. When the inhibitor reacts with chymotrypsin or methylamine, the resulting derivatives yield slightly higher Rg-values, 4.7 and 4.85 nm, respectively. The data of the native protein are consistent with a model, the projection of which resembles the letter V and which is formed by the two identical halves of an elliptic cylinder with semi-axes of 2.1 and 5.5 nm and a length of 11 nm. This elliptic cylinder model also explained the scattering from the monomeric complement proteins C3 and C4, as well as that from the monomers of the dimeric and tetrameric alpha 2-macroglobulin family of proteins (Osterberg, R., et al. (1991), Biochemistry 30, 7873-7878). Due to the conformational change occurring when the thiol ester bond is split, the cleft in the V-form seems to be closed; and as a result, the models of the chymotrypsin and methylamine derivatives are more compact than that of the native protein.

Acute-Phase Proteins↗
PubMed1994

Plasma alpha-1-antiproteinase from the Mongolian gerbil, Meriones unguiculatus: isolation, partial characterization, sequencing of cDNA, and implications for molecular evolution.

alpha-1-Antiproteinase (also called alpha-1-proteinase inhibitor or alpha-1-antitrypsin) with a molecular mass of 56 kDa was purified from plasma of the Mongolian gerbil, Meriones unguiculatus, to apparent homogeneity. It inhibited trypsin, chymotrypsin, elastase, and plasmin, but not kallikrein or thrombin. Eight cDNA clones coding for this protein were isolated from a liver cDNA library and sequenced. They contained the same coding regions consisting of a 24-residue signal peptide and a 382-residue mature protein. The reactive site sequence (P3-P3) was Val-Pro-Met-Ser-Ile-Pro, characteristic of alpha-1-antiproteinase of orthodox type [Suzuki, Y. et al. (1991) J. Biol. Chem. 266, 928-932]. A molecular phylogenetic tree of 11 orthologous inhibitors, constructed on the basis of the synonymous substitution rate, shows (i) that the reactive site region is highly conserved as compared to the other part of the molecule, which contrasts with the generally accepted view that the reactive site region of serpins is strongly hypervariable, and (ii) that the myomorphs (gerbil, rat, and two species of mouse, i.e. Mus domesticus and Mus caroli) and the caviomorph (guinea pig) fail to consist of a monophyletic order, which also contradicts the traditional taxonomy based on the morphology. In the present tree, the guinea pig joins the lagomorph (rabbit), and is rather widely separated from the myomorph branch. The result, however, supports the recent hypothesis based on the molecular evolution of several other proteins that the guinea pig does not belong to the same order as the myomorph, and the caviomorphs should be elevated in taxonomic rank and conferred an ordinal status distinct from the rodents.

Amino Acid Sequence↗
PubMed1994

The target antigen of anti-tubular basement membrane antibody-mediated interstitial nephritis.

Our previous studies showed that 54 kD and 48 kD tubular basement membrane (TBM) proteins were the major form of the target antigen involved in anti-TBM antibody-mediated tubulo-interstitial nephritis in humans. In those studies, we isolated the 54 kD glycoprotein (named gp54) from collagenase-digested bovine TBM. NH2-terminal amino acid sequencing indicated that gp54 represented a newly defined glycoprotein. In this study, we further characterized the target antigen, using mouse monoclonal antibodies to gp54 and polyclonal anti-gp54 peptide antibody. Two monoclonal antibodies (H79 and H80) were established, and they reacted, by immunofluorescence, predominantly with the proximal TBM of humans, rabbits, and Wistar, Sprague-Dawley, and Brown-Norway rats, but not with that of Lewis rats. They were also fixed by blotting intensely to the 54 kD component and weakly to the 48 kD component of collagenase-digested human TBM. In vivo transfer of H79 to Wistar rats showed extensive linear binding of mouse IgG to the TBM and the basal membrane of the small intestine; however, no pathologic changes were seen by light microscopy. The anti-gp54 peptide antibody reacted with both the 54 kD and 48 kD TBM components of human TBM. mRNA was prepared from rabbit kidneys, and fractionated to enrich mRNA encoding the 54 kD and 48 kD peptides. On in vitro translation experiments with the mRNA fraction, the 54 kD and 48 kD peptides were immunoprecipitated with anti-gp54 antibodies. These findings indicate that the 54 kD and 48 kD components are encoded with different mRNA, but that they share the same antigenic epitope.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Isolation and characterization of mouse countertrypin, a new trypsin inhibitor belonging to the mammalian fetuin family.

A novel trypsin inhibitor, tentatively named countertrypin, was isolated from mouse plasma in an apparently homogeneous state. Countertrypin is a 53-kDa glycoprotein having about 30% carbohydrate, and did not cross-react immunologically with either mouse alpha 1-antiproteinase (also called alpha 1-proteinase inhibitor or alpha 1-antitrypsin) or contrapsin. Countertrypin had no inhibitory activity against chymotrypsin, pancreatic elastase, neutrophil elastase, thrombin, plasmin, plasma kallikrein, pancreatic kallikrein, clotting factor Xa, or papain. This inhibitory spectrum does not correspond to any of the known plasma proteinase inhibitors that have been well characterized in human or other mammals. NH2-terminal amino acid sequence analysis of the intact molecule and three peptides obtained by CNBr digestion revealed that a total of 93 amino acid residues could be aligned with stretches in human alpha 2-HS glycoprotein, bovine fetuin, and rat pp63 (rat fetuin). Human alpha 2-HS glycoprotein and bovine fetuin prepared without use of ethanol inhibited trypsin and pancreatic and neutrophil elastases. These results indicate that mouse countertrypin is a new member of the mammalian fetuin family, which possibly has the trypsin-inhibiting activity in common.

Amino Acid Sequence↗
PubMed1993

Structure and expression of the mRNA encoding urinary stone protein (osteopontin).

The chemical nature of urinary stone protein is poorly understood. We have sequenced a cDNA of urinary calcium oxalate stone protein extracted with EDTA. cDNA sequences showed complete identity between urinary stone protein and human osteopontin. Osteopontin protein was detected by staining with Stains-All, which specifically stains phosphoproteins, and by digestion with the highly specific protease thrombin, demonstrating that urinary calcium oxalate stones consist of osteopontin protein. We used a technique of in situ hybridization to detect osteopontin mRNA in the kidney. In control rats, distal tubular cells were sporadically positive, and proximal tubular cells and glomeruli were negative for osteopontin mRNA. A rat model of stone formation was induced with glyoxylic acid. In stone-forming rats, staining of distal tubular cells was remarkably increased, but proximal tubular cells and glomeruli were still negative. Immunostaining for the osteopontin protein also revealed that epithelial cells of distal tubules were weakly positive in control rats and significantly increased in stone-forming rats, although proximal tubular cells and glomeruli were negative. Northern blot analysis showed a significant increase of osteopontin mRNA in stone-forming rats in proportion to the dosage and the duration of the stone-inducing drugs. These results show that osteopontin in the kidney is presumably involved in urinary stone formation as the stone matrix.

Animals↗
PubMed1993

Sequencing of a urinary stone protein, identical to alpha-one antitrypsin, which lacks 22 amino acids.

We have extracted and purified proteins from calcium containing urinary stones with 4 M guanidine chloride and sequenced the amino acids of the proteins. The protein of approximately 49kDa was defined as human alpha-one antitrypsin (AT, from 23rd to 42nd amino acids of NH2-terminal) by amino acid sequence analysis. The ratio of the amount of AT to total proteins was 34.9% analyzed by densitometer. AT is presumably involved in stone formation as a coprecipitating substance because equilibrium dialysis revealed that AT has no affinity for calcium.

Amino Acid Sequence↗
PubMed1993

Rabbit plasma alpha-1-antiproteinase S-1: cloning, sequencing, expression, and proteinase inhibitory properties of recombinant protein.

A cDNA clone coding for the isoform S-1 of alpha-1-antiproteinase (also called alpha-1-proteinase inhibitor or alpha-1-antitrypsin) was isolated from rabbit liver cDNA library and sequenced. The cDNA consists of 1,426 nucleotides including 5' and 3' noncoding regions and codes for 413 amino acid residues including a signal peptide of 24 residues. The nucleotide and deduced amino acid sequences show 95.5 and 95.2% homologies, respectively, with the F isoform which occurs more abundantly in the rabbit serum than the S isoform. Of the 20 amino acid differences between the two isoforms, nine are located in a stretch of 15 amino acids encompassing the reactive site region, suggesting that these genes have diverged from each other by a nonrandom mechanism. A hypothesis is proposed that the domestication of animal is responsible for the extremely high evolutionary rate in the serpin reactive site region. Prokaryotic expression plasmids were constructed from the cDNA, transfected into Escherichia coli, and expressed. Partially purified recombinant protein inhibited elastase, but did not inhibit trypsin when a small substrate was used. The recombinant S-1 form, however, protected trypsin from inactivation by soybean trypsin inhibitor, a property characteristic of alpha-macroglobulins or rodent murinoglobulins. It is known that there are two types of interaction between serpin and proteinase: (i) most serpins form a stable equimolar complex with the enzyme, resulting in the enzyme inhibition and (ii) some serpins act as a substrate rather than as an inhibitor, resulting in the loss of inhibitory activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Hamster alpha-macroglobulin and murinoglobulin: comparison of chemical and biological properties with homologs from other mammals.

alpha-Macroglobulin and murinoglobulin were purified to homogeneity from Syrian hamster plasma and their properties were compared with those of their respective homologs from other mammals. The trypsin-inhibiting capacity of hamster murinoglobulin was much weaker than those of rat and mouse murinoglobulins. Hamster alpha-macroglobulin was cleaved by trypsin at a number of sites whereas the human homolog was split essentially only in a "bait" region into two fragments of similar size. Hamster alpha-macroglobulin treated with methylamine differed from that treated with trypsin in the electrophoretic mobility, intensity of fluorescence induced by binding of bis(8-anilino-1-naphthalenesulfonate), and plasma clearance pattern, whereas virtually no difference was observed between the human homologs treated in the same manner. The reaction of hamster alpha-macroglobulin with methylamine, as measured by the generation of thiol groups and the decrease in trypsin-protein amidase activity, was much slower than that of the human homolog. Trypsin in a complex with hamster alpha-macroglobulin retained its fibrinolytic activity, but this was not the case for human or rabbit alpha-2-macroglobulin. These results suggest that, compared with the human homolog, hamster alpha-macroglobulin is more loosely packed in the native state, undergoes conformational change more slowly on treatment with methylamine, and less efficiently hinders the access of proteinaceous substrates to trapped proteinase. The serum concentration of hamster alpha-macroglobulin was 6.9 mg/ml, or about 3-fold higher than that of the human type, and showed little change during the acute-phase reaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Amidohydrolases↗
PubMed1992

Molecular cloning and sequencing of cDNA encoding urinary stone protein, which is identical to osteopontin.

We have sequenced a cDNA of urinary stone protein. cDNA sequences show complete homology between urinary stone protein and human osteopontin (bone sialoprotein) (nucleotides 265-886 and 1183-1424). Osteopontin is a recently discovered bone matrix protein which has been implicated in mediating mineral formation within bone extracellular matrix. This result shows that osteopontin is presumably involved in stone formation as stone matrix.

Base Sequence↗
PubMed1991

Cloning, structure and expression of cDNA for mouse contrapsin and a related protein.

A cDNA clone (lambda MC-2) for contrapsin, a serine-proteinase inhibitor, was isolated from a lambda ZAP mouse liver cDNA library. The 1.6 kb cDNA insert of lambda MC-2 contained an open reading frame that encodes a 418-residue polypeptide (46,970 Da), in which a signal peptide of 21 residues was identified by comparison with the N-terminal sequence of the purified protein. The predicted structure (MC-2) also contained other peptide sequences determined by Edman degradation. Four potential sites for N-linked glycosylation were found in the molecule, accounting for the difference in molecular mass between the predicted form and the purified protein (63 kDa). Further screening of the cDNA library with an EcoRI-EcoRI fragment (510 bp) of lambda MC-2 as a probe yielded another cDNA clone (lambda MC-7), which encodes a 418-residue polypeptide (MC-7) with a calculated mass of 47,010 Da. MC-2 showed 83% similarity at the amino acid level to MC-7, in contrast with 44% similarity to alpha 1-proteinase inhibitor. The possible reactive site (P1-P'1) for serine proteinase is suggested to be Lys-Ala for MC-2 and Ser-Arg for MC-7. Northern-blot analysis revealed that both MC-2 and MC-7 mRNAs have the same size of 1.8 kb and are markedly induced in response to acute inflammation. Construction of the expression plasmids pSVMC-2 and pSVMC-7 and their transfection into COS-1 cells demonstrated that pSVMC-2 directs the synthesis of a 63 kDa form whereas pSVMC-7 expresses a 56 kDa form. The difference in molecular mass between the two may be explained by the fact that the MC-7 sequence contains three potential sites for N-glycosylation, one site less than that of MC-2.

Amino Acid Sequence↗
PubMed1991

Molecular cloning and sequence analysis of cDNAs coding for guinea pig alpha 1-antiproteinases S and F and contrapsin.

The cDNAs encoding two isoforms, S (slow) and F (fast), of alpha 1-antiproteinase (also referred to as alpha 1-antitrypsin or alpha 1-proteinase inhibitor) as well as contrapsin were obtained by screening lambda gt11 cDNA library prepared fro inflamed guinea pig liver. The sequence analyses of these cDNAs and NH2-terminal peptides of the purified proteins revealed that both isoforms of alpha 1-antiproteinase consist of 405 amino acid residues including a signal peptide of 24 residues and that contrapsin consists of 410 amino acid residues with the same length of the signal peptide. Guinea pig contrapsin had 89, 88, 62, 42, and 41% homology to its own alpha 1-antiproteinases F and S, rat alpha 1-antiproteinase, mouse and rat contrapsins, respectively. This suggests that guinea pig contrapsin is not orthologous to mouse and rat contrapsins and that it developed from a much later duplication of alpha 1-antiproteinase gene after the guinea pig had diverged from the murine lineage. The available data suggest that the reactive site region of alpha 1-antiproteinase can be categorized into orthodox and unorthodox types: the former has P3-P'3 consensus sequence of Xaa-Pro-Met-Ser-Xaa-Pro, where Xaa is Leu, Ile, Val, or Met, while the latter, which occurs in species having multiple alpha 1-antiproteinase isoforms, has the sequence whose P1 Met has changed to other amino acids. Thus, the reactive site region of the orthodox type, which occurs in all seven mammals examined to date, is highly conserved. This is in marked contrast to the fact that the same region is hypervariable among the paralogous proteins belonging to the serpin superfamily.

Amino Acid Sequence↗
PubMed1991

Purification, characterization, and acute phase response of plasma alpha-1-antiproteinase in the hamster, Mesacricetus auratus.

1. alpha-1-Antiproteinase (also called alpha-1-antitrypsin or alpha-1-proteinase inhibitor) with a molecular mass of 60 kDa was purified to apparent homogeneity from hamster plasma. 2. It inhibited elastase, chymotrypsin and trypsin, but did not significantly affect pancreatic kallikrein, plasma kallikrein or plasmin. 3. It has the same N-terminal heptapeptide sequence as that of rat alpha-1-antiproteinase. 4. Its plasma level decreased after injection of bacterial lipopolysaccharide.

Acute-Phase Proteins↗