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T Matsui

Publications and source records attributed to T Matsui.

At least 667 records · Page 37Linked to original sources
PubMed1991

Cell adhesive activity of two animal lectins through different recognition mechanisms.

Cell adhesive activity of two animal lectins, frog (Rana catesbeiana) S-type 14K lectin and echinoidin (a C-type lectin from sea urchin plasma), was studied with human rhabdomyosarcoma (RD) cells. RD cells attached to and spread on plastic plates coated with each lectin. Cell adhesion by the frog lectin was completely inhibited by the addition of lactose or asialofetuin glycopeptide. Echinoidin-induced cell adhesion was only inhibited by peptide GRGDS. Since echinoidin is known to contain an RGD-sequence, our results clearly indicate that this sequence is active as the cell adhesive signal. These results suggest that some of the animal lectins may function as a cell adhesive molecule rather than using the carbohydrate-recognition mechanism.

Amino Acid Sequence↗
PubMed1991

Carbohydrate analysis of human von Willebrand factor with horseradish peroxidase-conjugated lectins.

Human von Willebrand factor (vWF) immobilized on a polyvinylidene difluoride membrane was subjected to binding assay with a series of horseradish peroxidase-conjugated lectins. The protein was reactive with concanavalin A, Ricinus communis agglutinin 120, wheat germ agglutinin and Ulex europaeus agglutinin I (UEA-I) but not with peanut agglutinin before sialidase treatment. These reactivities were consistent with the major oligosaccharide structure reported except for UEA-I. The reactivity with UEA-I was greatly decreased after digestion of the protein with either alpha-L-fucosidase or peptide-N-glycosidase F, but no significant decrease was observed after mild alkaline treatment or delipidation. vWF and UEA-I have been independently used as a good marker for human endothelial cells. Our results indicate that vWF itself contains UEA-I reactive sugar chains in its Asn-linked oligosaccharides.

Carbohydrates↗
PubMed1991

Biphasic rise caused by extracellular ATP in intracellular calcium concentration in bovine adrenocortical fasciculata cells.

We examined the effect of extracellular ATP on intracellular calcium concentration ([Ca2+]i) in bovine adrenocortical fasciculata cells. The suspended cells and the monolayer cells on coverslips were loaded with fura2. We found that ATP caused a rapid transient rise [Ca2+]i in dose-dependent manner in the presence of extracellular Ca2+ and that the rise in [Ca2+]i caused by ATP was biphasic. We did not observe the second phase in the absence of extracellular Ca2+. These results suggest that the first rise in [Ca2+]i caused by ATP is due to Ca2+ release from intracellular Ca2+ stores and subsequent rise due to Ca2+ influx across the plasma membrane. Furthermore, we found that the first phase of the monolayer cells consisted of two peaks. So it is possible that Ca2+ release from intracellular Ca2+ stores caused by ATP is induced by two different manners in adrenocortical fasciculata cells. In addition, monolayer cells are more useful than suspended ones in the examination of Ca2+ mobilization in adrenocortical fasciculata cells.

Adenosine Triphosphate↗
PubMed1991

Purification and characterization of beta-galactoside binding lectin from frog (Rana catesbeiana) eggs.

A beta-galactoside-binding lectin, a homodimer composed of 14kDa subunits, was purified from unfertilized eggs of the frog Rana catesbeiana by asialofetuin-Sepharose 4B affinity column chromatography. The lectin was solubilized from eggs by addition of neither haptenic sugar nor detergent and showed a unique characteristic that it requires neither Ca++ nor SH-reagent for its hemagglutination activity. However, the partial amino acid sequence indicated that the lectin belongs to a family of soluble 14kDa beta-galactoside-binding lectins (14K-lectin) widely distributed in vertebrates and classified as S type lectins. These results indicate that a 14K-lectin is present as the free form in unfertilized frog eggs, presenting the first structural evidence for the presence of a soluble 14K-lectin in the amphibian eggs.

Amino Acid Sequence↗
PubMed1991

The retinoblastoma gene functions as a growth and tumor suppressor in human bladder carcinoma cells.

The product of the human retinoblastoma gene (RB) is a nuclear phosphoprotein that is thought to function as a tumor suppressor. Mutations of RB frequently occur in human bladder carcinoma. To investigate the significance of the functional loss of this gene in bladder cancer, an RB expression plasmid (pBARB) under control of the human beta-actin promoter was transfected into the bladder carcinoma cell line HTB9, which lacks RB expression. Marker-selected transfectants that expressed RB protein were identified by immunoblotting and immunohistochemical staining. In selected clones, stable RB expression has persisted over 1 yr under standard culture conditions with 10% serum. However, RB expression caused major alterations of HTB9 growth properties both in vitro and in vivo. RB+ transfectants lacked the ability to form colonies in semi-solid medium, and their growth rate was significantly decreased in 3% serum. In addition, the tumorigenicity of these transfectants was markedly decreased. Tumors that formed in nude mice were much smaller and had a longer latency period but were indistinguishable microscopically from those produced by parental cells. Slower growing tumors were RB+, as measured by nuclear staining of their RB protein and by a normal RB protein pattern on immunoblots. These findings support the concept that the RB gene acts as both a growth and tumor suppressor in bladder cancer cells.

Actins↗
PubMed1991

Interleukin-1 enhances the response of osteoblasts to platelet-derived growth factor through the alpha receptor-specific up-regulation.

Both platelet-derived growth factor (PDGF) and interleukin-1 (IL-1) are produced by activated macrophages and are thought to contribute to bone remodeling, but their precise roles remain to be clarified. The interaction between PDGF and IL-1 was, therefore, studied in normal osteoblast-like cells (MC3T3-E1). The expression of alpha- and beta-PDGF receptors on MC3T3-E1 cells was detected by RNA blot analysis and confirmed by immunoblot analysis. PDGF-induced chemotactic as well as mitogenic activities were synergistically enhanced by either IL-1 alpha or IL-1 beta (40 units/ml) pretreatment in serum-free medium, although IL-1 alone did not show any detectable chemotactic activities. This biological enhancement by IL-1 was accompanied by a selective increase of alpha-PDGF receptor expression, following the augmentation of alpha receptor autophosphorylation and inositol phosphate hydrolysis induced by PDGF-AA. These findings suggest that PDGF and IL-1 are jointly involved in the bone-remodeling microenvironment as local coupling factors.

Blotting, Northern↗
PubMed1991

Immobilization of ultra-thin layer of monoclonal antibody on glass surface.

When preparing an affinity column and a biosensor, it is desirable to immobilize a unimolecular layer of pure protein on a matrix. In this work, we tried to immobilize a monoclonal antibody on a surface of a glass test-tube as a model, to confirm the stability of this ultra-thin layer by an enzyme immunoassay, and to estimate the thickness of the layer on a slide glass by Fourier transform infrared reflection spectrometry. A new test-tube was washed and dried. The tube was filled with 5% 3-aminopropyltriethoxysilane. The 3-aminopropylsilylated surface was treated with glutaraldehyde and 5.6.10(-2) mg/ml solution of a normal mouse monoclonal antibody. The Schiff base between glutaraldehyde and the antibody was further reduced with 7.9.10(-3)% NaBH4. The tube was washed with 0.05% Tween 20 to block non-specific binding. The antibody immobilized on the surface was measured by an enzyme immunoassay based on a reaction of anti-mouse immunoglobulin G labelled with alkaline phosphatase, with which p-nitrophenol was produced from p-nitrophenylphosphate as a substrate. Meanwhile, various amounts of the antibody were immobilized on slide glasses in the same manner. The antibody on each surface was measured by Fourier transform infrared reflection spectrometry. The antibody immobilized under the final conditions was detectable by the enzyme immunoassay, and stable at 4 degrees C for ten days. The antibody on the slide glass was a unimolecular layer, as judged from the Fourier transform infrared spectra referred to -CONH- band semiquantitatively. Thus, we found the optimal conditions for immobilizing an ultra-thin layer of the monoclonal antibody on the glass surface.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Platelet-derived growth factor B chain homodimer enhances chemotaxis and DNA synthesis in normal osteoblast-like cells (MC3T3-E1).

We demonstrate that recombinant platelet-derived growth factor B chain homodimer (PDGF-BB) could induce both the chemotactic activity and the DNA synthesis in a normal osteoblast-like cell line (MC3T3-E1). Cell migration toward recombinant human PDGF-BB was observed with the modified Boyden chamber technique. Maximum chemotaxis was exhibited at 25 ng/ml of PDGF-BB. DNA synthesis as indicated by [3H]-thymidine incorporation was also enhanced about 4-fold at 25-100 ng/ml PDGF-BB. Our results suggested that PDGF might be one of the candidates among local coupling factors for bone remodeling.

Animals↗
PubMed1991

Amino acid sequence and molecular characterization of a D-galactoside-specific lectin purified from sea urchin (Anthocidaris crassispina) eggs.

The complete amino acid sequence of a 11.5-kDa subunit of D-galactoside binding lectin purified from sea urchin (Anthocidaris crassispina) eggs is presented. The 105-residue sequence of the subunit was determined by analysis of the intact S-carbamoylmethylated protein and peptides generated by digestion with Achromobacter protease I or Staphylococcus aureus V8 protease. The lectin exists as a disulfide-linked homodimer of two subunits; the dimeric form is essential for hemagglutination activity. However, the monomeric form obtained by partial reduction retains the carbohydrate binding capacity. Neither Ca2+ nor SH reagent is essential for hemagglutination or carbohydrate binding. The sequence has no similarity to that of any known protein and apparently represents a new type of galactoside binding lectin.

Amino Acid Sequence↗
PubMed1991

Isolation and chemical characterization of two structurally and functionally distinct forms of botrocetin, the platelet coagglutinin isolated from the venom of Bothrops jararaca.

Two distinct forms of botrocetin, the von Willebrand factor (vWF)-dependent platelet coagglutinin isolated from the venom of the snake Bothrops jararaca, were purified and characterized structurally and functionally. The apparent molecular mass of the one-chain botrocetin was 28 kDa before and 32 kDa after reduction of disulfide bonds, while that of the two-chain botrocetin was 27 kDa before and 15/14.5 kDa after reduction. Amino acid composition of the two species revealed a similar high content of potentially acidic residues (greater than 60 Asx and Glx residues/molecule) but significant differences in the content of Cys and Phe residues. The NH2-terminal sequence of the one-chain botrocetin was Ile-Ile/Val-Ser-Pro-Pro-Val-Cys-Gly-Asn-Glu-. Two constituent polypeptides of the two-chain botrocetin showed similar but different NH2-terminal sequences, distinct from that of the one-chain species: (alpha) Asp-Cys-Pro-Ser-Gly-Trp-Ser-Ser-Tyr-Glu- and (beta) Asp-Cys-Pro-Pro-Asp-Trp-Ser-Ser-Tyr-Glu-. The carbohydrate content of both species was less than 2% of the total mass, and the pI was 4.0-4.1 for the one-chain species, and 4.6, 5.3-5.4, and 7.7-7.8 for the two-chain species. No free sulfhydryl group was detected in each species. Both types of botrocetin were resistant to proteolysis at neutral pH. Incubation of 125I-labeled one-chain botrocetin with the crude venom solution resulted in no detectable structural change. On a weight basis, the two-chain botrocetin was 34 times more active than the one-chain form in promoting vWF binding to platelets.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1991

Beta-subunits of equine chorionic gonadotropin and lutenizing hormone with an identical amino acid sequence have different asparagine-linked oligosaccharide chains.

The glycoprotein hormones, equine chorionic gonadotropin (eCG) and lutenizing hormone (eLH), possess a beta-subunit with an identical amino acid sequence. The Asn-linked oligosaccharide chains of eCG beta and eLH beta were quantitatively liberated as tritium-labeled oligosaccharides by hydrazinolysis followed by N-acetylation and NaB3H4-reduction. Paper electrophoresis in combination with sialidase digestion and solvolytic desulfation indicated that eCG beta contained neutral and sialylated oligosaccharides, while eLH beta contained neutral, sialylated, sulfated, and both sialylated and sulfated oligosaccharides. In addition, elution profiles on a Bio-Gel P-4 column of the neutralized oligosaccharide mixtures of eCG beta and eLH beta were different, indicating that the molecular masses of oligosaccharides of the two glycoproteins are different. Therefore, this suggests that the structures of the Asn-linked oligosaccharide chains of eCG beta and eLH beta are different although they have an identical amino acid sequence.

Amino Acid Sequence↗