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Y Emori

Publications and source records attributed to Y Emori.

At least 127 records · Page 7Linked to original sources
PubMed1987

Molecular cloning and sequencing of cDNA for rat cathepsin H. Homology in pro-peptide regions of cysteine proteinases.

A cDNA for rat cathepsin H was isolated and sequenced. The deduced protein comprising 333 amino acid residues is composed of a typical signal sequence (21 residues), a pro-peptide region (92 residues) and a mature enzyme region (220 residues). The amino acid sequence in the pro-peptide region, in particular, residues Phe-(-41) to Ser-(-29) of cathepsin H, is highly homologous to the pro-peptide regions of other cysteine proteinases. This homologous region may play a role in the processing of cysteine proteinases.

Amino Acid Sequence↗
PubMed1987

Molecular cloning of a cysteine proteinase inhibitor of rice (oryzacystatin). Homology with animal cystatins and transient expression in the ripening process of rice seeds.

A cDNA clone for a cysteine proteinase inhibitor of rice (oryzacystatin) was isolated from a lambda gt10 cDNA library of rice immature seeds by screening with synthesized oligonucleotide probes based on partial amino acid sequences of oryzacystatin. A nearly full-length cDNA clone was obtained which encoded 102-amino acid residues. The amino acid sequence of oryzacystatin deduced from the cDNA sequence was significantly homologous to those of mammalian cystatins, especially family 2 cystatins. Oryzacystatin contained the sequence Gln-Val-Val-Ala-Gly conserved among most members of the cystatin superfamily. The gene for oryzacystatin was transcribed into a single mRNA species of about 700 nucleotides. The content of mRNA reached its highest level 2 weeks after flowering and then gradually decreased to undetectable levels at 10 weeks. This feature of transient expression is coordinate with that of glutelin (a major storage protein), although the expression of oryzacystatin precedes that of glutelin by about 1 week.

Amino Acid Sequence↗
PubMed1987

Calcium-activated neutral protease and its endogenous inhibitor. Activation at the cell membrane and biological function.

The structures of calcium-activated neutral protease (CANP) and its endogenous inhibitor elucidated recently have revealed novel features with respect to their structure-function relationship and enzyme activity regulation. The protease is regarded as a proenzyme which can be activated at the cell membrane in the presence of Ca2+ and phospholipid, and presumably regulates the functions of proteins, especially membrane-associated proteins, by limited proteolysis. Protein kinase C is hydrolysed and activated by CANP at the cell membrane to a cofactor-independent form. These results are reviewed and the possible involvement of CANP in signal transduction is discussed.

Animals↗
PubMed1987

Calcium-activated neutral protease inhibitor from rabbit erythrocytes lacks the N-terminal region of the liver inhibitor but retains three inhibitory units.

Endogenous inhibitors for calcium-activated neutral protease (CANP) were purified from rabbit erythrocytes and liver. The purified inhibitors showed single bands but with significantly different mobilities on sodium dodecylsulfate-polyacrylamide gel electrophoresis. Peptide mapping and sequencing analyses have revealed that the erythrocyte inhibitor (429 residues) retains the C-terminal three repetitive units of the liver inhibitor (639 residues), which contains four potential repetitive units for inhibition of CANP. The erythrocyte and liver inhibitors inhibited 3 and 4 moles of CANP on the basis of the molecular weights of 46,000 and 68,000, respectively.

Amino Acid Sequence↗
PubMed1987

A fragment of an endogenous inhibitor produced in Escherichia coli for calcium-activated neutral protease (CANP) retains an inhibitory activity.

A C-terminal fragment of an endogenous rabbit liver inhibitor for calcium-activated neutral protease (CANP) was produced in Escherichia coli and its inhibitory activity was examined after purification. The truncated inhibitor (373 amino acid residues), which contains two internal repeat structures, inhibits 2 mol CANP whereas the native liver inhibitor (639 residues), containing four internal repeat structures, inhibits 4 mol CANP. This supports the hypothesis that the repeating unit is the functional unit of inhibition. The results also indicate that post-translational modification of the inhibitor is not essential for inhibition.

Amino Acid Sequence↗
PubMed1987

Endogenous inhibitor for calcium-dependent cysteine protease contains four internal repeats that could be responsible for its multiple reactive sites.

A cDNA encoding an endogenous inhibitor, termed calpastatin, for calcium-dependent cysteine protease (calpain, EC 3.4.22.17) was cloned by screening rabbit cDNA libraries with a synthetic oligodeoxynucleotide probe based on the partial amino acid sequence of the purified protein. The deduced amino acid sequence contains 718 amino acid residues (Mr, 76,964), and the mature protein corresponds to the deduced sequence from the 80th residue of the primary translation product (resultant Mr, 68,113). This deduced molecular weight is significantly lower than that determined by NaDodSO4/polyacrylamide gel electrophoresis, suggesting the possibility that the inhibitor is post-translationally modified. The sequence of the mature inhibitor contains four consecutive internal repeats approximately 140 amino acid residues long, each of which might be responsible for the inhibitory activity. Calpastatin is apparently different from a typical cysteine protease inhibitor (cystatin), suggesting that the mechanism of inhibition of calcium-dependent cysteine protease by the inhibitor might be different from that of other cysteine proteases by cystatin.

Amino Acid Sequence↗
PubMed1987

E-F hand structure-domain of calcium-activated neutral protease (CANP) can bind Ca2+ ions.

The cDNA fragments corresponding to the domains with four consecutive E-F hand structures in the large and small subunits of chicken and rabbit calcium-activated neutral protease (CANP) were inserted into an expression vector (pUC8 or pUC18). The resulting plasmids were used to transform E. coli, and isopropyl-1-thio-beta-D-galactoside (IPTG)-inducible expression was performed. The resulting four kinds of E-F hand structure-domains (the chicken large subunit, rabbit high- and low-calcium-requiring large subunits, and rabbit small subunit) were purified and analyzed for their calcium-binding abilities and capacities by the microscale filter assay. Most of the E-F hand structures could bind calcium and 2 or 4 mol of Ca2+ ions bound to the four consecutive E-F hand structures. The calcium-binding affinity of the E-F hand structures in the large subunit roughly corresponds to the calcium concentration required for its CANP activity.

Amino Acid Sequence↗
PubMed1986

Gene organization of the small subunit of human calcium-activated neutral protease.

The gene for the small subunit of human calcium-activated neutral protease was isolated and sequenced. It is 11 kb long and comprises 11 exons. No TATA or CAT box was found upstream of the possible transcription initiation sites, but there are three so-called G-C box sequences and one G-C box-like sequence, which are usually found in "house-keeping" genes. The first exon (exon 1) contains only the 5'-noncoding sequence and exon 2 encodes the Gly-rich hydrophobic domain. Each of the four calcium-binding loop regions is encoded by one exon (exons 7-10). The intron breakpoints in the C-terminal calcium-binding domain (exons 4-11) completely coincide with those of the chicken large subunit gene. These findings suggest that the small and large subunits have evolved from the same ancestral calcium-binding protein and have retained the original gene organization.

Amino Acid Sequence↗
PubMed1986

Complete amino acid sequence of the large subunit of the low-Ca2+-requiring form of human Ca2+-activated neutral protease (muCANP) deduced from its cDNA sequence.

The complete amino acid sequence of the large subunit (catalytic subunit) of human low-Ca2+-requiring-calcium-activated neutral protease (muCANP) was deduced from its cDNA base sequence. It is composed of 714 amino acid residues and its sequence is highly homologous to the chicken CANP sequence determined previously. Human muCANP, like chicken CANP, has a clear 4-domain structure, and their fundamental structures are essentially the same, although their Ca2+ sensitivities are significantly different. The role of each domain in the Ca2+ sensitivity and protease activity of CANP is discussed on the basis of sequence comparison.

Amino Acid Sequence↗
PubMed1986

Isolation and sequence analyses of cDNA clones for the large subunits of two isozymes of rabbit calcium-dependent protease.

Two sets of cDNA clones were isolated from cDNA libraries prepared from poly(A+) RNA of rabbit lung and spleen by screening with the cDNA probe for the large subunit (80-kDa subunit) of chicken calcium-dependent protease (Ca2+-protease; Ohno, S., Emori, Y., Imajoh, S., Kawasaki, H., Kisaragi, M., and Suzuki, K. (1984) Nature 312, 566-570). The two sets of clones were identified as cDNA clones for two Ca2+-protease isozymes with high (mu-type) and low (m-type) calcium sensitivities from a comparison of the primary structures deduced from the nucleotide sequences with partial amino acid sequences from the two isozymes. The cDNA clones for the 80-kDa subunits of the mu- and m-type Ca2+-proteases contained, in total, about 1.5- and 2.2-kilobase cDNA inserts, respectively, which correspond roughly to the C-terminal halves of the coding regions and the entire 3'-noncoding regions. The two isozymes are encoded by two distinct mRNA species present in all the tissues examined, although the amount of mRNA significantly differs among the various tissues. Four E-F hand structures, typical calcium-binding structures in various calcium-binding proteins such as calmodulin, were detected in the C-terminal regions of both isozymes, as in the case of chicken Ca2+-protease. Comparison of the amino acid sequences of the two rabbit isozymes and the corresponding region of the chicken enzyme revealed marked homology, which indicates that these three enzymes have the same evolutionary origin. Furthermore, we suggest that the mu-type rabbit Ca2+-protease, rather than the m-type, is similar to chicken Ca2+-protease, which is regarded as an m-type enzyme in the C-terminal region. The evolution and molecular basis of the differences in calcium sensitivities of the Ca2+-proteases are discussed.

Amino Acid Sequence↗
PubMed1986

Isolation and sequence analysis of cDNA clones for the small subunit of rabbit calcium-dependent protease.

We have isolated and sequenced cDNA clones for the small subunit (30-kDa subunit) of rabbit calcium-dependent protease (Ca2+-protease) using synthesized oligodeoxynucleotide probes based on the partial amino acid sequence of the protein. A nearly full-length cDNA clone containing the total amino acid coding sequence was obtained. From the deduced sequence, the following conclusions about possible functions of the protein are presented. The kDa subunit comprises 266 residues (Mr = 28,238). The N-terminal region (64 residues) is mainly composed of glycine (37 residues) and hydrophobic amino acids and may interact with the cell membrane or an organelle. The sequence of the C-terminal 168 residues is highly homologous to the corresponding C-terminal region of the large subunit (80-kDa subunit) which has been identified as the calcium-binding domain. This region of the 30-kDa subunit contains four E-F hand structures and presumably binds Ca2+, as in the case of the 80-kDa subunit. Thus, the 30-kDa subunit may play important roles in regulating enzyme activity and/or possibly in determining the location of the Ca2+-protease. The marked sequence homology of the C-terminal regions of the two subunits may indicate that the calcium-binding domains have evolved from the same ancestral gene.

Amino Acid Sequence↗
PubMed1986

Gene structure of calcium-dependent protease retains the ancestral organization of the calcium-binding protein gene.

The gene structure of calcium-dependent protease (Ca2+-protease) was determined. It comprises at least 21 exons, and these were assigned to the 4 functional domains of the protease. The protease domain does not show clear correlation between exons and functional units, but the calmodulin-like calcium-binding domain shows strong correlation. Each of the 4 consecutive calcium-binding regions in the C-terminal part of Ca2+-protease is encoded by one exon. This gene structure supports the idea that the 4 calcium-binding regions of calcium-binding proteins such as calmodulin arose by 2 steps of gene duplication.

Animals↗
PubMed1986

Structure and function of the small (30K) subunit of calcium-activated neutral protease (CANP).

Calcium-activated neutral protease (CANP), a typical intracellular protease, is composed of a catalytic 80K subunit (80K) and a 30K subunit (30K) of unknown function. The structure of rabbit CANP 30K was examined to clarify its role in the enzyme function. It has a clear two-domain structure composed of 266 amino acid residues. The N-terminal domain presumably determines the location of CANP, whereas the C-terminal domain is a calmodulin-like Ca2+-binding domain and regulates CANP activity.

Amino Acid Sequence↗
PubMed1983

Transcriptional regulation of three double-stranded RNA segments of bacteriophage phi 6 in vitro.

Three double-stranded RNA segments of bacteriophage phi 6 (L, M, and S) were transcribed in vitro by a virion-associated RNA polymerase. Regulation of L transcription was distinct from regulation of M and S transcription. Transcription of the L segment, which codes for early proteins, required manganous ion and high concentrations of all four ribonucleoside triphosphates and was inhibited by polyamines such as spermine. Transcription of the M and S segments, which code for late proteins, required manganous or magnesium ion and relatively low concentrations of all ribonucleoside triphosphates except GTP and was enhanced by polyamines. Optimal conditions for L transcription were more stringent than those for M and S transcription. These two apparently different patterns produced in in vitro transcription presumably reflect the two distinct in vivo transcription patterns; i.e., (i) similar amounts of three single-stranded RNA species were transcribed from the three corresponding segments of double-stranded RNA (early pattern) and (ii) a much larger amount of single-stranded RNA species was transcribed from M and S segments than from the L segment (late pattern). The early transcription pattern may be changed into the late pattern by a change of environment, such as substrate concentration. This suggests that the different enzymatic properties under the different environmental conditions of the virion-associated transcriptase are responsible for the transcriptional regulation throughout the infection cycle of bacteriophage phi 6.

Cations, Divalent↗