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F Kimizuka

Publications and source records attributed to F Kimizuka.

30 records · Page 2Linked to original sources
PubMed1990

Characterization of a functional domain of human calpastatin.

Expression plasmids were constructed from the cDNA of human calpastatin to examine the contribution to the inhibition of calpain of highly conserved sequences in each of four repetitive domains. A series of deletion derivatives of domain 1 proteins, truncated at either the amino or carboxy terminus, were produced in E. coli. Deletion from the amino terminus past the amino terminal conserved sequence decreased the inhibition. When the middle conserved sequence, the M-sequence, was further deleted, no inhibition was detected, but deletion from the carboxy terminus past the carboxy terminal conserved sequence did not decrease the inhibition until the M-sequence was reached. Nuclear magnetic resonance and circular dichroism spectra showed that domain 1 has an unfolded structure. Peptides that contained the M-sequence and some neighboring sequences were synthesized to measure the minimum size of the inhibitory peptide, which was the M-sequence with the next six residues on the amino terminal side.

Amino Acid Sequence↗
PubMed1990

Inhibition of lung metastasis by synthetic and recombinant fragments of human fibronectin with functional domains.

We have investigated the antimetastatic effect of synthetic or recombinant peptides containing the functional domains of fibronectin on experimental and spontaneous lung metastases of murine tumor cells. CS1 peptide which is present within type III homology connecting segment (IIICS) as well as C-274 (cell-binding domain) were able to inhibit experimental lung metastasis when co-injected intravenously (iv) with B16-BL6 melanoma cells, while H-271 (heparin-binding domain) could not. In the spontaneous metastasis model, multiple iv administrations of CS1 or C-274 after surgical excision of primary tumors caused a significant reduction of metastatic colonies in the lung. Both CS1 and C-274 significantly inhibited cell adhesion and migration to fibronectin-coated substrates when added freely in solution. CS1 peptide also inhibited the cell adhesion and migration to laminin-coated substrates, but C-274 did not. H-271 did not have any inhibitory effect on cell adhesion or migration to either of the substrates. Similarly, CS1 inhibited tumor invasion to both Matrigel/fibronectin- and Matrigel/laminin-coated filters, whereas C-274 inhibited the invasion to only Matrigel/fibronectin-coated filter. These results indicate that CS1 peptide of fibronectin, lacking the Arg-Gly-Asp-containing domain, actively inhibits tumor metastases in spontaneous and experimental metastasis models. The use of such a peptide might offer a promising therapeutic approach for combatting or preventing cancer metastasis.

Amino Acid Sequence↗
PubMed1989

Primary structure and functional expression of h-caldesmon complementary DNA.

Recently, the two Mr forms of caldesmon (Mr's in the range of 120-150kDa and 70-80kDa as judged by SDS-PAGE) have been identified. h-Caldesman (high Mr 120-150kDa caldesmon) is predominantly expressed in smooth muscles, and l-caldesmon (low Mr 70-80kDa caldesmon) in non-muscle cells. In this paper, we report the nucleotide sequence of chick embryo gizzard h-caldesmon cDNA and its translation into amino acid sequence. This sequence predicts a protein of 771 amino acids with a Mr of 88,743. The central portion of this sequence is composed of a 10-fold repeat of conserved amino acid sequence containing 13-15 amino acids. Further, a recombinant protein produced in Escherichia coli containing the full-length h-caldesmon cDNA has been characterized. Although the Mr of h-caldesmon predicted from amino acid sequence is 88,743, native and recombinant proteins show the same mol. wt. with 150kDa as measured by SDS-PAGE. This discrepancy may be due to the acidic amino acid-rich sequences at the N-terminal and central portions. A recombinant protein produced in E. coli possesses calmodulin-, F-actin- and tropomyosin-binding abilities in common with the native h-caldesmon.

Amino Acid Sequence↗
PubMed1989

A novel cell adhesive protein engineered by insertion of the Arg-Gly-Asp-Ser tetrapeptide.

A tetrapeptide Arg-Gly-Asp-Ser (RGDS) has been shown to be a versatile cell recognition signal of extracellular matrix components for the interaction with cells. We introduced the RGDS tetrapeptide into a truncated form of protein A, a staphylococcal immunoglobulin-binding protein, by inserting an oligonucleotide cassette encoding the tetrapeptide into the coding region of the protein A expression vector pRIT2T. The mutagenized protein was capable of not only binding to immunoglobulin G but also mediating cell attachment and spreading onto an inert substrate. Cell adhesion mediated by the mutagenized protein was inhibitable by a synthetic peptide Gly-Arg-Gly-Asp-Ser but not by a related peptide Gly-Arg-Gly-Glu-Ser, confirming that the inserted RGDS tetrapeptide served as a recognition signal for cell adhesion. Furthermore, the RGDS-containing protein was capable of adhering cells onto an immunoglobulin-coated surface which could not by itself support cell adhesion. Thus, the cell adhesive and immunoglobulin binding activities of the mutagenized protein appear to function coordinately. The protocol described here is essentially applicable to any protein and, therefore, provides a general principle in tailoring novel multifunctional proteins having cell adhesive activity.

Amino Acid Sequence↗
PubMed1989

35 kDa fragment of h-caldesmon conserves two consensus sequences of the tropomyosin-binding domain in troponin T.

Using a tropomyosin-coupled affinity column, we have demonstrated a direct association between the chymotryptic 35 kDa fragment of h-caldesmon, which is located at the C-terminal of the parent molecule, and gizzard tropomyosin. We have subsequently determined the nucleotide sequence of cDNA clones encoding the 35 kDa fragment from the cDNA library prepared from chick embryo gizzards, and have deduced the amino acid sequence. Calculating from the predicted sequence, the 35 kDa fragment is composed of 306 amino acid residues. In agreement with the tropomyosin-binding ability, the 35 kDa fragment conserves two consensus sequences of the tropomyosin-binding domain in troponin T. These results suggest that the 35 kDa fragment of h-caldesmon, at least in part, has a common property to the striated muscle troponin T.

Amino Acid Sequence↗
PubMed1989

Isolation and characterization of two monoclonal antibodies that recognize remote epitopes on the cell-binding domain of human fibronectin.

Two monoclonal anti-fibronectin antibodies that inhibit fibronectin-mediated cell adhesion have been established and characterized. One antibody, FN12-8, inhibited attachment of rat kidney fibroblasts on the fibronectin-coated substrate in a concentration-dependent manner, attaining a maximal inhibition of greater than 85% at 850 micrograms/ml. Another antibody, FN30-8, caused about 70% inhibition at a concentration as low as 0.85 microgram/ml, although further increase of the antibody concentration did not significantly augment the inhibitory effect. Immunoblot analysis with defined proteolytic fragments revealed that both antibodies are directed to the cell-binding domain of fibronectin. The epitopes for these antibodies were further narrowed down using recombinant cell-binding fragments expressed in Escherichia coli. FN12-8 recognized the 11.5-kDa cell-binding fragment previously characterized by Pierschbacher et al. (1981, Cell 26, 259-267), suggesting that FN12-8 blocks the Arg-Gly-Asp (RGD) cell adhesion signal. FN30-8 could not bind this fragment but did recognize a longer cell-binding fragment containing additional greater than 111 amino acid residues upstream of the 11.5-kDa fragment. Since the RGD-dependent cell adhesion seems to require another signal located at a region 50-160 residues upstream of the 11.5-kDa fragment for full activity, FN30-8 may exert its inhibitory effect by blocking the latter signal.

Amino Acids↗
PubMed1989

The primary structure of porcine liver acylamino acid-releasing enzyme deduced from cDNA sequences.

Two overlapping cloned cDNAs encoding the entire amino acid sequences of the subunits of acylamino acid-releasing enzyme (AARE) [EC 3.4.19.1] have been isolated from porcine liver cDNA lambda gt10 cDNA libraries and sequenced. Sequence analyses of the cDNA and several Achromobacter protease I-digested peptides of the purified protein revealed that porcine liver AARE consists of four identical subunits, and each comprising a single chain of 732 amino acids with acetylmethionine at the N-terminus.

Animals↗
PubMed1989

cDNA cloning of human calpastatin: sequence homology among human, pig, and rabbit calpastatins.

cDNA of human calpastatin, an inhibitor protein specific for calpain (EC 3.4.22.17; Ca2(+)-dependent cysteine proteinase) was isolated by screening of a library prepared from human liver mRNA with pig calpastatin cDNA fragment as a probe. The primary structure of human calpastatin was deduced from the nucleotide sequence of the cDNA and compared with that of pig and rabbit calpastatins already reported. Human calpastatin consisted of 673 amino acid residues and had 78% and 77% identity to pig or rabbit calpastatins, respectively. Human calpastatin had a domain structure with four internally repetitive sequences and one N-terminal non-homologous sequence like the other calpastatins. Human calpastatin had two deletions, 22 and 13 residues long in domain L and domain 1, respectively, compared to pig or rabbit calpastatins.

Amino Acid Sequence↗
PubMed1988

Regulatory effect of a synthetic CRP recognition sequence placed downstream of a promoter.

A series of plasmids were constructed in which a promoter was introduced into a lac-based operon fusion vector. A perfectly symmetrical oligonucleotide of 22-bp corresponding to an idealized binding site for cAMP receptor protein (CRP) of E. coli was chemically synthesized. The synthetic CRP site was placed between the promoter and the lacZ structural gene with varying distances from the promoter. Specific binding of cAMP-CRP complex to the synthetic CRP site was shown by a gel retardation and a DNase I footprinting assays. Plasmid constructs were transformed into crp+ and crp- cells carrying a chromosomal deletion of the lac genes. The regulatory effect of the inserted CRP site was examined by comparing the beta-galactosidase activity and the levels of RNA transcript in two cells harboring the plasmids. We found a strong inhibitory effect of the CRP site in the presence of cAMP and CRP when it was placed close to the promoter. When the CRP site was placed far downstream of the promoter, a moderate repression of transcription was observed.

Base Sequence↗
PubMed1985

Interaction of the restriction endonuclease ScaI with its substrates.

The kinetic constants of the site-specific endonuclease, ScaI, for various substrates were determined. We estimated Vmax and Km for octa-, deca-, dodeca-, and hexadecanucleotides and for plasmid pBR322 DNA. Vmax for these substrates were close, but Km were quite different (in decreasing order, octa- greater than deca-, dodeca-, hexadeca- greater than pBR322). The results were discussed with respect to the tertiary structure of substrate.

DNA Restriction Enzymes↗