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Y Emori

Publications and source records attributed to Y Emori.

At least 91 records · Page 5Linked to original sources
PubMed1991

Rat calpastatin has diverged primary sequence from other mammalian calpastatins but retains functionally important sequences.

Rat calpastatin was cloned for cDNA and sequenced. It comprises 603 amino acid residues and contains four repeats of approx. 140 amino acid residues, each of which has TIPPxYr sequence responsible for calpain-inhibitory activity. However, rat calpastatin has three deletions of 30-40 amino acid residues in the nonessential regions for the inhibitory activity, and consequently, the deduced molecular size is significantly smaller than those of other mammalian calpastatins.

Amino Acid Sequence↗
PubMed1991

Gene organization of oryzacystatin-II, a new cystatin superfamily member of plant origin, is closely related to that of oryzacystatin-I but different from those of animal cystatins.

The gene structure of oryzacystatin-II, a new cystatin superfamily member of rice seed origin, was determined. It spans approximately 2.5 kbp and comprises 3 exons. The number of exons and the intron-breakpoints coincide with those of oryzacystatin-I, the first well-defined plant cystatin. However, no similar sequences were observed between the two oryzacystatin genes in 5'-upstream regulatory regions, even though both are expressed specifically during the ripening stage of rice seeds. The gene organization of these two plant cystatins is generally different from that of animal cystatins.

Amino Acid Sequence↗
PubMed1991

Phospholipase C genes display restriction fragment length polymorphisms between the genomes of normotensive and hypertensive rats.

The genomic loci of four distinct phospholipase C genes (PLC-beta, PLC-gamma I, PLC-delta and PLC-gamma II) were examined for restriction fragment length polymorphisms (RFLPs) between the genomes of three normotensive [Sprague-Dawley, Donryu and Wistar-Kyoto (WKY)] and two closely related hypertensive [spontaneously hypertensive (SHR) and SHR stroke-prone (SHR-SP)] rat strains. The RFLPs observed between SHR and WKY were classified into three types. Type I RFLPs are those observed at 4.3 kilobase (kb) and 1.9 kb by AvaI digestion for PLC-gamma probe and at 1.9 kb by AccI digestion for PLC-beta probe, where RFLP banding patterns are conserved in two hypertensive (SHR and SHR-SP) and one normotensive (Sprague-Dawley) strains. Type II RFLPs are those observed by AccI, BamHI, EcoRI and PstI digestions for PLC-beta probe, where RFLP pattern observed in SHR is shared by one normotensive (Sprague-Dawley) strain but not by SHR-SP, WKY or Donryu rats. Type III RFLPs are those detected at 6.3 kb band by Bg/II digestion for PLC-beta probe and at 1.0 kb by BamHI digestion for PLC-gamma II probe, where RFLP pattern observed in SHR is shared by two normotensive rats other than WKY. No RFLP was found for PLC-gamma I probe after testing 13 restriction enzymes. Since PLC plays a pivotal role in regulating the intracellular calcium concentration and the intracellular signal transduction, these RFLPs may offer a valuable tool for the analysis of genomic predisposition for hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Molecular cloning and functional analysis of three subunits of yeast proteasome.

The genes encoding three subunits of Saccharomyces cerevisiae proteasome were cloned and sequenced. The deduced amino acid sequences were homologous not only to each other (30 to 40% identity) but also to those of rat and Drosophila proteasomes (25 to 65% identity). However, none of these sequences showed any similarity to any other known sequences, including various proteases, suggesting that these proteasome subunits may constitute a unique gene family. Gene disruption analyses revealed that two of the three subunits (subunits Y7 and Y8) are essential for growth, indicating that the proteasome and its individual subunits play an indispensable role in fundamental biological processes. On the other hand, subunit Y13 is not essential; haploid cells with a disrupted Y13 gene can proliferate, although the doubling time is longer than that of cells with nondisrupted genes. In addition, biochemical analysis revealed that proteasome prepared from the Y13 disrupted cells contains tryptic and chymotryptic activities equivalent to those of nondisrupted cells, indicating that the Y13 subunit is not essential for tryptic or chymotryptic activity. However, the chymotryptic activity of the Y13 disrupted cells is not dependent on sodium dodecyl sulfate (SDS), an activator of proteasome, since nearly full activity was observed in the absence of SDS. Thus, the activity in proteasome of the Y13 disrupted cells might result in unregulated intracellular proteolysis, thus leading to the prolonged cell cycle. These results indicate that cloned proteasome subunits having similar sequences to the yeast Y13 subunit are structural, but not catalytic, components of proteasome. It is also suggested that two subunits (Y7 and Y8) might occupy positions essential to proteasome structure or activity, whereas subunit Y13 is in a nonessential but important position.

Amino Acid Sequence↗
PubMed1991

Sequence comparison among subunits of multicatalytic proteinase.

The cDNAs for a number of multicatalytic proteinase (MCP) subunits have been cloned, characterized, and their primary structures have been determined. The mechanism for how MCP demonstrates its multicatalytic nature, especially protease activities, however, is still obscure, since no sequences similar to known protease sequences can be found in the sequences of MCP subunits thus far determined. To explain this fact, we propose a structural model for MCP: MCP consists of two classes of subunits, structural and catalytic, and the structural subunits constitute a "test-tube"-like container in which the other catalytic subunits sit and react with substrate. Most of the observations thus far obtained can be explained easily by this hypothesis, although various other possibilities are not excluded.

Amino Acid Sequence↗
PubMed1991

Oryzacystatins as the first well-defined cystatins of plant origin and their target proteinases in rice seeds.

Two cystatins occur in mature seeds of the rice, Oryza sativa L. japonica, which are named oryzacystatin I (OC-I) and oryzacystatin II (OC-II). These are highly homologous to each other and are significantly homologous to cystatin superfamily members of animal origin, especially to family-2 cystatins. However, both lack disulfide bonds as in the case of family-1 cystatins (stefins). Each of OC-I and OC-II thus seems to be chimerical of family-1 and family-2 cystatins, and we propose that a new category such as "phytocystatin" be opened for these cystatins of plant origin. For specificity it was observed that OC-I inhibits papain 100 times more efficiently than cathepsin H, whereas, OC-II inhibits cathepsin H 100 times more efficiently than papain. A cysteine proteinase, named oryzain alpha, exists in germinating rice seeds. cDNA cloning studies have disclosed that two other related species, named oryzain beta and gamma, are also present. In respect to the amino acid sequence, oryzain alpha and beta are homologous to papain and oryzain gamma is homologous to cathepsin H. These observations suggest the possibility that either or both of oryzain alpha and beta are target enzymes of OC-I and oryzain gamma is a target enzyme of OC-II.

Amino Acid Sequence↗
PubMed1991

Papain-inhibitory activity of oryzacystatin, a rice seed cysteine proteinase inhibitor, depends on the central Gln-Val-Val-Ala-Gly region conserved among cystatin superfamily members.

Oryzacystatin, a cysteine proteinase inhibitor occurring in rice seeds, contains a particular glycine residue (Gly5) near the NH2-terminal position, and the sequence Gln53-Val54-Val55-Ala56-Gly57 in a central part of the molecule. Both are conserved among most members of the cystatin superfamily. We have found from Escherichia coli expression studies that the NH2-terminal 21 residues of oryzacystatin are not essential for its papain-inhibitory activity, and that the conserved pentapeptide region may be indispensable [Abe, K., Emori, Y., Kondo, H., Arai, S., & Suzuki, K. (1988) J. Biol. Chem. 263, 7655-7659]. Here we present more detailed data based on quantitative analyses of the inhibitory activities of NH2- and COOH-terminally truncated oryzacystatin and site-directed mutants at the Gln-Val-Val-Ala-Gly region. The data indicate the following results. (1) The truncated mutants lacking the NH2-terminal 21 residues or the COOH-terminal 11 residues exhibit potent papain-inhibitory activity equivalent to the activity of wild oryzacystatin. (2) However, neither the mutant lacking the NH2-terminal 38 residues nor that lacking the COOH-terminal 35 residues is completely able to inhibit papain. (3) Site-directed mutants at the Gln residue of the Gln-Val-Val-Ala-Gly region have drastically reduced papain-inhibitory activities: the Gln----Pro mutant is completely inactive and the Gln----Leu mutant has an approximately 150 times higher Ki value than wild-type oryzacystatin.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1990

Molecular cloning of cDNAs for two subunits of rat multicatalytic proteinase. Existence of N-terminal conserved and C-terminal diverged sequences among subunits.

cDNA clones for two subunits (designated subunits K and L) of rat liver multicatalytic proteinase (MCP) were isolated using oligonucleotide probes synthesized according to their partial amino acid sequences. The encoded polypeptides of subunits K and L consisted of 255 and 261 amino acid residues with calculated molecular mass of 28.3 kDa and 29.5 kDa, respectively. Northern blot analysis revealed that subunits K and L were expressed in all tissues examined and their expression patterns were almost identical. The deduced amino acid sequences showed no similarities to known protein sequences other than the recently reported sequences of rat and Drosophila MCP subunits. Sequence comparison of MCP subunits of rat and Drosophila revealed that the N-terminal two-thirds of the sequence (especially the N-terminal approximately 20 residues) is conserved, but the C-terminal third of the sequence shows no similarity, suggesting functional and structural roles for both regions. Implications for the structural and functional aspects of MCP subunits are discussed based on the sequence similarity.

Amino Acid Sequence↗
PubMed1990

Reactivity of Limulus amoebocyte lysate towards (1----3)-beta-D-glucans.

The structure activity relationship for beta-D-glucans for the gelation of the amoebocyte lysates of the horseshoe crab (Limulus) has been investigated. beta-D-Glucans that had no (1----3) linkages induced little or no gelation. The (1----3)-beta-D-glucans curdlan (unbranched), grifolan (approximately 33% branched), schizophyllan (approximately 33% branched), lentinan (approximately 40% branched). SSG (approximately 50% branched), and OL-2 (approximately 66% branched) induced significant gelation. The optimum concentration for gelation was correlated with the content of branching. Single chain (rather than a triple helix) conformation and higher molecular weight were associated with higher reactivity.

Animals↗
PubMed1990

Two distinct cystatin species in rice seeds with different specificities against cysteine proteinases. Molecular cloning, expression, and biochemical studies on oryzacystatin-II.

Oryzacystatin (oryzacystatin-I) is a proteinaceous cysteine proteinase inhibitor (cystatin) in rice seeds and is the first well defined cystatin of plant origin. In this study we isolated cDNA clones for a new type of cystatin (oryzacystatin-II) in rice seeds by screening with the oryzacystatin-I cDNA probe. The newly isolated cDNA clone encodes 107 amino acid residues whose sequence is similar to that of oryzacystatin-I (approximately 55% of identity). These oryzacystatins have no disulfide bonds, and so could be classified as family-I cystatins; however, the amino acid sequences resemble those of family-II members more than family-I members. Oryzacystatin-I and -II are remarkably distinct in two respects: 1) their specificities against cysteine proteinases; and 2) the expression patterns of their mRNAs in the ripening stage of rice seeds. Oryzacystatin-I inhibits papain more effectively (Ki 3.0 x 10(-8) M) than cathepsin H (Ki 0.79 x 10(-6) M), while oryzacystatin-II inhibits cathepsin H (Ki 1.0 x 10(-8) M) better than papain (Ki 0.83 x 10(-6) M). The mRNA for oryzacystatin-I is expressed maximally at 2 weeks after flowering and is not detected in mature seeds, whereas the mRNA for oryzacystatin-II is constantly expressed throughout the maturation stages and is clearly detected in mature seeds. Western blotting analysis using antibody to oryzacystatin-II showed that, as is the case with oryzacystatin-I, oryzacystatin-II occurs in mature rice seeds. Thus, these two oryzacystatin species are believed to be involved in the regulation of proteolysis caused by different proteinases.

Amino Acid Sequence↗
PubMed1990

Molecular cloning of a ubiquitously distributed microtubule-associated protein with Mr 190,000.

A heat-stable microtubule-associated protein (MAP) with apparent molecular weight of 190,000 is a major non-neural MAP which distributes ubiquitously among bovine tissues (termed here MAP-U). Previously we reported that microtubule-binding chymotryptic fragments of MAP-U and tau contain a common assembly-promoting (AP) sequence of 22 amino acid residues (Aizawa, H., Kawasaki, H., Murofushi, H., Kotani, S., Suzuki, K., and Sakai, H. (1989) J. Biol. Chem. 264, 5885-5890). We isolated cDNA clones for MAP-U containing the whole coding sequence. Northern blot analysis revealed that a major species of MAP-U mRNA is 5 kilobases in length and is expressed ubiquitously among bovine tissues. Nucleotide sequence analysis revealed the complete amino acid sequence of MAP-U which consists of 1,072 amino acid residues. Analysis of the deduced amino acid sequence of MAP-U indicated that this molecule is clearly divided into two domains in terms of electrostatic charge distribution: an amino-terminal acidic domain (residues 1-640) and a carboxyl-terminal basic domain (residues 641-1072). The amino-terminal domain of MAP-U shows no significant sequence homology with other known protein sequences including neural MAPs, tau, and MAP-2. The amino-terminal domain of MAP-U contains unique 18 1/2 repeats of 14-amino acid motif which have not been observed in other MAPs. The carboxyl-terminal domain of MAP-U is further divided into three regions: a Pro-rich region (residues 641-880), an AP sequence region (residues 881-1003), and a short hydrophobic tail (residues 1004-1072). The Pro-rich region is mainly composed of five species of amino acid residues, Pro, Ala, Lys, Ser, and Thr. The AP sequence region contains four tandem repeats of AP sequences, and thus, this region is considered to play a leading role in the interaction of MAP-U with microtubules.

Amino Acid Sequence↗
PubMed1990

Isolation and characterization of a gamma-type phosphoinositide-specific phospholipase C (PLC-gamma 2).

A novel bovine spleen phosphoinositide-specific phospholipase C (PLC) has been identified with respect to immunoreactivity with four independent antibodies against each of the PLC isoenzymes, and purified to near homogeneity by sequential column chromatography. Spleen contains three of the isoenzymes: two different gamma-types [gamma 1 and gamma 2, originally named as PLC-gamma [Rhee, Suh, Ryu & Lee (1989) Science 244, 546-550] and PLC-IV [Emori, Homma, Sorimachi, Kawasaki, Nakanishi, Suzuki & Takenawa (1989) J. Biol. Chem. 264, 21885-21890] respectively] and delta-type of the enzyme, but PLC-gamma 1 is separated from the PLC-gamma 2 pool by the first DEAE-cellulose column chromatography. Subsequently, PLC-delta is dissociated on the third heparin-Sepharose column chromatography. The purified enzyme has a molecular mass of 145 kDa on SDS/polyacrylamide-gel electrophoresis and a specific activity of 12.8 mumol/min per mg with phosphatidylinositol 4,5-bisphosphate as substrate. This enzyme activity is dependent on Ca2+ for hydrolysis of all these phosphoinositides. None of the other phospholipids examined could be its substrate at any concentration of Ca2+. The optimal pH of the enzyme is slightly acidic (pH 5.0-6.5).

Animals↗
PubMed1990

Organization and primary sequence of multiple genes coding for the apopolysialoglycoproteins of rainbow trout.

We have shown that the mRNAs for apopolysialoglycoproteins (apoPSGP) of rainbow trout contain various numbers of a repetitive sequence of 39 base-pairs encoding mature apoPSGP, and that this sequence is bordered by highly homologous 5' and 3' regions encoding pre-, pro- and telopeptides. These mRNAs are thought to be transcribed from different genes that constitute a large multiple gene family (more than 100 members). Here, we have determined the structures of several members of the apoPSGP gene family. The results show that two of three genomic DNA fragments contain two independent apoPSGP genes in the same orientation with unrelated sequences intervening. Five characterized genes have essentially the same organization and sequence. Each gene has four exons, and CAAT and TATA sequences were found in the 5'-flanking regions. However, two noteworthy differences were observed among the five genes; a diversity in the number of the 39 base-pair repeats, also observed among the cDNA clones, and a one-base polymorphism in the 39 base-pair repeat, which causes an amino acid change. This polymorphism was not detected among the cDNA clones obtained. The boundary positions of the genes are various and contain no transposon-like structures. The variation in the number of repeats and the absence of a rule for bordering positions of the genes suggest that apoPSGP genes may have been amplified by gene duplications, unequal recombination, and selection of chromosomes having larger numbers of apoPSGP genes.

Amino Acid Sequence↗
PubMed1990

Production and separation of peptides from proteins stained with Coomassie brilliant blue R-250 after separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Proteins stained with Coomassie brilliant blue on polyacrylamide gels were digested with lysylendopeptidase in the presence of sodium dodecyl sulfate. Peptide production was similar to that under ordinary conditions of digestion. Peptides were recovered easily and efficiently from the gel pieces and separated by HPLC. The present method for preparation of peptides from proteins separated by sodium dodecyl sulfate gel electrophoresis is quite simple and can be used for sequence analysis of proteins in general at the subnanomolar level.

Amino Acid Sequence↗
PubMed1990

Molecular cloning and characterization of cDNAs coding for apopolysialoglycoproteins in cherry salmon (Oncorhynchus masou) eggs.

Recently we have cloned the cDNAs and genomic DNAs for apopolysialoglycoproteins (apoPSGPs) of Salmo gairdneri (rainbow trout) [Sorimachi, H., Emori, Y., Kawasaki, H., Kitajima, K., Inoue, S., Suzuki, K., & Inoue, Y. (1988) J. Biol. Chem. 262, 17678-17684], and the sequence analyses have indicated that the mRNAs for apoPSGPs vary in length and contain different numbers of identical 39-bp repeating units encoding the tridecapeptide (Asp-Asp-Ala-Thr-Ser-Glu-Ala-Ala-Thr-Gly-Pro-Ser-Gly) as well as highly conserved sequences encoding pre-, pro-, and telo-peptide regions. In this study we isolated cDNA clones for yamame (cherry salmon, river resident form; Oncorhynchus masou ishikawai) apoPSGP using a genomic DNA fragment for rainbow trout apoPSGP as a probe. The nucleotide sequence analyses revealed that the structures of mRNAs for yamame apoPSGP including the noncoding regions are essentially identical to those for rainbow trout, showing 90% sequence identity. Within the repeating region, 4 bp out of the 39 were replaced, producing a different tridecapeptide, Asp-Asp-Ala-Thr-Ser-Glu-Ala-Ala-Thr-Gly-Pro-Ser-Ser. This tridecapeptide is unique to yamame and common among all cDNAs obtained from yamame. Genomic Southern blot analysis showed that the yamame apoPSGP genes constituted a multiple gene family with a similar gene organization to that of rainbow trout. Oligodeoxynucleotide probes (18 bases) synthesized based on specific sequences for the yamame repeating unit hybridized only to the yamame DNA and not to the rainbow trout DNA, and vice versa.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1990

The multi-purpose camera: a new anterior eye segment analysis system.

A new device for the analysis of the anterior eye segment was developed. With this device, a Scheimpflug slit image and a retroillumination image can be taken separately using a CCD camera. The quality of the images obtained was satisfactory enough for analysis. The data obtained were stored and analyzed on an almost real-time level using an on-line computer. The menu for the data analysis provided for this device includes multilinear densitometry, with planimetry, area densitometry, measurement of anterior chamber depth and thickness of lens layers, determination of chamber angle and positioning of implanted intraocular lenses, and measurement of opaque areas in the retroillumination image.

Animals↗
PubMed1990

A novel member of the calcium-dependent cysteine protease family.

In the course of cDNA cloning of the large subunits of human mu- and mCANPs, a novel cDNA clone encoding a putative calcium-dependent cysteine protease homologous to but distinct from both mu- and m-types was found. The encoded protein, designated tentatively as p94, is composed of four domains similar to those found in other CANP large subunits, but includes three unique regions that have no homology to other CANPs. These unique sequences might be involved in regulating the activation and/or determining the intracellular localization of p94. Since the mRNA for p94 is five times more abundant than that for the CANP small subunit in skeletal muscle, it is possible that p94 does not associate with the small subunit in vivo. In contrast to the ubiquitous expression of mu- and m-types, the mRNA for p94 is expressed only in skeletal muscle. Besides acting as a protease, p94 may act as a skeletal muscle specific regulatory protein like troponin C.

Amino Acid Sequence↗