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1.
Epithelial tubes are the functional units of many organs, and proper tube geometry is crucial for organ function. Here, we characterize serrano (sano), a novel cytoplasmic protein that is apically enriched in several tube-forming epithelia in Drosophila, including the tracheal system. Loss of sano results in elongated tracheae, whereas Sano overexpression causes shortened tracheae with reduced apical boundaries. Sano overexpression during larval and pupal stages causes planar cell polarity (PCP) defects in several adult tissues. In Sano-overexpressing pupal wing cells, core PCP proteins are mislocalized and prehairs are misoriented; sano loss or overexpression in the eye disrupts ommatidial polarity and rotation. Importantly, Sano binds the PCP regulator Dishevelled (Dsh), and loss or ectopic expression of many known PCP proteins in the trachea gives rise to similar defects observed with loss or gain of sano, revealing a previously unrecognized role for PCP pathway components in tube size control.  相似文献   

2.
Dorn GW 《Cell metabolism》2007,5(5):326-327
Angiogenesis is essential for normal and neoplastic tissue growth. In a recent issue of Nature, Komuro and colleagues (Sano et al., 2007) describe how p53 expression in hypertrophying heart muscle impairs HIF-1-mediated neovascularization and contributes to functional decompensation of pressure-overload cardiac hypertrophy.  相似文献   

3.
4.
Previously we identified an unusual potential dual Akt/protein kinase B consensus phosphorylation motif in the protein Synip (RxKxRS(97)xS(99)) with serine 99 as a unique Akt2, but not Akt1 or for Akt3, substrate phosphorylation site. Although we have previously reported that serine 99 to phenylalanine (S99F-Synip) resulted in a constitutive inhibition of insulin-stimulated Glut4 translocation, a recent report indicated that Synip serine 99 to alanine mutant (S99A-Synip) failed to inhibit insulin-stimulated Glut4 translocation [H. Sano, S. Kane, E. Sano, G.E. Lienhard, Synip phosphorylation does not regulate insulin-stimulated GLUT4 translocation, Biochem. Biophys. Res. Commun. 332 (2005) 880-884]. To address this apparent discrepancy, we have now examined the S99A-Synip mutant and find that this mutant behaves essentially identical to S99F-Synip in that overexpression inhibits insulin-stimulated Glut4 translocation and is incapable of undergoing insulin-stimulated Syntaxin4 dissociation. These data are consistent with Synip serine 99 phosphorylation required for insulin-stimulated Glut4 translocation.  相似文献   

5.
结直肠癌发病率高,早期诊断困难,威胁着全世界人民的健康。近几年窄带成像技术(Narrow Band Imaging,NBI)发展迅速,大大改善了结直肠镜下图像的清晰程度,NBI辅助下的结直肠镜检查在早期诊治肠癌方面具有重要意义。为了进一步优化结直肠镜的诊断效能,多种NBI辅助的结直肠镜下的结直肠病变分型被提出。针对病变的表面形态、颜色分布以及微血管的形态与走形,Sano分型、Jikei分型、Showa分型、Hiroshima分型和NICE(Narrow-Band Imaging International Colorectal Endoscopic)分型相继被提出。其中NICE分型以良好的学习曲线和诊断效能被广泛认可和应用。  相似文献   

6.
The xylem-limited bacterium Xylella fastidiosa is the causal agent of several plant diseases, most notably Pierce''s disease of grape and citrus variegated chlorosis. We report the isolation and characterization of the first virulent phages for X. fastidiosa, siphophages Sano and Salvo and podophages Prado and Paz, with a host range that includes Xanthomonas spp. Phages propagated on homologous hosts had observed adsorption rate constants of ∼4 × 10−12 ml cell−1 min−1 for X. fastidiosa strain Temecula 1 and ∼5 × 10−10 to 7 × 10−10 ml cell−1 min−1 for Xanthomonas strain EC-12. Sano and Salvo exhibit >80% nucleotide identity to each other in aligned regions and are syntenic to phage BcepNazgul. We propose that phage BcepNazgul is the founding member of a novel phage type, to which Sano and Salvo belong. The lysis genes of the Nazgul-like phage type include a gene that encodes an outer membrane lipoprotein endolysin and also spanin gene families that provide insight into the evolution of the lysis pathway for phages of Gram-negative hosts. Prado and Paz, although exhibiting no significant DNA homology to each other, are new members of the phiKMV-like phage type, based on the position of the single-subunit RNA polymerase gene. The four phages are type IV pilus dependent for infection of both X. fastidiosa and Xanthomonas. The phages may be useful as agents for an effective and environmentally responsible strategy for the control of diseases caused by X. fastidiosa.  相似文献   

7.
A novel phosphate-induced gene, phi-2, has been identified by its induction on addition of phosphate to phosphate-starved tobacco BY-2 cells. The predicted gene product of phi-2 has significant homology to a group of bZIP proteins involved in ABA-signaling pathways, and phi-2 also responded to ABA treatment. A previously isolated phosphate-induced gene, phi-1, (Sano et al. (1999) Plant Cell Physiol. 40: 1) was also responsive to ABA. Although phosphate addition induced semi-synchronous cell division in phosphate-starved tobacco BY-2 cells, ABA adversely affected cell division. Detailed examination revealed that the high levels of phosphate required to induce semi-synchronous cell division seemed to be perceived as indicators of stress by the cells. One of the stress indicators perceived by the cells is a cytoplasmic pH change, to which phi-2 and phi-1 genes respond. The different components of the cell's response to phosphate induction are discussed.  相似文献   

8.
An improved procedure is reported for large-scale preparation of photosystem I (PS-I) vesicles from thylakoid membranes of barley (Hordeum vulgare L.). The PS-I vesicles contain polypeptides of molecular masses 82, 18, 16, 14, and 9 kDa in an apparent molar ratio of 4:2:2:1:2. The 18-, 16-, and 9-kDa polypeptides were purified to homogeneity after exposure of the PS-I vesicles to chaotropic agents. The isolated 9-kDa polypeptide binds 65-70% of the zero-valence sulfur of denatured PS-I vesicles, and the remaining 30-35% is bound to P700-chlorophyll a-protein 1. The N-terminal amino acid sequence (29 residues) of the 9-kDa polypeptide was determined. Comparison with the nucleotide sequence of the chloroplast genome of Marchantia polymorpha (Ohyama, K., Fukuzawa, H., Kohchi, T., Shirai, H., Sano, T., Sano, S., Umesono, K., Shiki, Y., Takeuchi, M., Chang, Z., Aota, S.-i., Inokuchi, H., and Ozeki, H. (1986) Nature 322, 572-574) and of Nicotiana tabacum (Shinozaki, K., Ohme, M., Tanaka, M., Wakasugi, T., Hayashida, N., Matsubayashi, T., Zaita, W., Chunwongse, J., Obokata, J., Yamaguchi-Shinozaki, K., Ohto, C., Torazawa, K., Meng, B. Y., Sugita, M., Deno, H., Kamogashira, T., Yamada, K., Kusuda, J., Takaiwa, F., Kato, A., Tohdoh, N., Shimada, H., and Sugiura, M. (1986) EMBO J. 5, 2043-2049) identified the chloroplast gene encoding the 9-kDa polypeptide. We designate this gene psaC. The complete amino acid sequence deduced from the psaC gene identifies the 9-kDa PS-I polypeptide as a 2[4Fe-4S] protein. Since P700-chlorophyll a-protein 1 carries center X, the 9-kDa polypeptide carries centers A and B. A hydropathy plot permits specific identification of the cysteine residues which coordinate centers A and B, respectively. Except for the loss of the N-terminal methionine residue, the primary translation product of the psaC gene is not proteolytically processed. P700-chlorophyll a-protein 1 binds 4 iron atoms and 4 molecules of acid-labile sulfide/molecule of P700. Each of the two apoproteins of P700-chlorophyll a-protein 1 contains the sequence Phe-Pro-Cys-Asp-Gly-Pro-Gly-Arg-Gly-Gly-Thr-Cys (Fish, L. E., Kück, U., and Bogorad, L. (1985) J. Biol. Chem. 260, 1413-1421). The stoichiometry of the component polypeptides of PS-I indicates the presence of four copies of this sequence per molecule of P700. Center X may be composed of two [2Fe-2S] centers bound to the 8 cysteine residues contained in these four segments.  相似文献   

9.
Metabolic events involved in energy metabolism were studied in order to evaluate the ATP-forming ability of Bacillus megaterium QM B1551 spores at the very early stage of germination. When heat-activated spores were germinated on glucose as a sole substrate, its oxidation into gluconate (catalyzed by glucose dehydrogenase, EC 1.1.1.47), the accompanying NADH formation, oxygen uptake, and RNA synthesis were initiated immediately after germination, even when anaerobic breakdown of 3-phosphoglycerate (an ATP source for spores) and the subsequent glucose metabolism via the phosphorylating pathway were impaired by potassium fluoride (KF). In contrast, fructose metabolism and the accompanying metabolic events did not begin until a few minutes after triggering of germination, and those events were entirely abolished by KF, indicating that fructose metabolism is initiated exclusively via its phosphorylation by the ATP derived from endogenous 3-phosphoglycerate. Thus those results provided further evidence for our previous proposal (Otani et al (1987) Microbiol. Immunol. 31: 967-974; Sano et al (1988) Biochem. Biophys. Res. Commun. 151: 48-52) that the first molecules of ATP in germinating spores can be efficiently generated via aerobic oxidation of NADH, which is formed by glucose dehydrogenase. Fluorescence monitoring of NADH in germinating spores also supported this conclusion.  相似文献   

10.
Plants respond differentially to wounding and pathogens usingdistinct signaling pathways, so that wound signals are transmittedto jasmonic acid (JA) which induces basic pathogenesis-related(PR) proteins, whereas pathogenic signals cause, in additionto JA, accumulation of salicylic acid (SA) which stimulatesproduction of acidic PR proteins. Transgenic tobacco plantsexpressing a gene for a small GTP binding protein respond abnormallyto mechanical wounding to produce SA and consequently acidicPR proteins, suggesting that wound signals cross with pathogensignaling pathways [Sano et al. (1994) Proc. Natl. Acad. Sci.USA 91: 10556]. This unusual signal crossing is associated witha highly sensitive wound-response of transgenic plants which,upon wounding, produce JA at least eighteen hours earlier thanwild-type plants. When wildtype plants are wounded in the presenceof the synthetic cytokinin, benzylaminopurine, production ofJA begins six hours earlier than in untreated samples, and alsoSA begins to accumulate. The cytokinin antagonist, 2-chloro-4-cyclohexylamino-6-ethylamino-s-triazine,erases these effects. Because transgenic plants constitutivelyproduce four-to six-fold higher amounts of endogenous cytokininsthan wild-type plants, it is concluded that cytokinins are indispensablefor control of endogenous levels of SA and JA. (Received April 23, 1996; Accepted June 10, 1996)  相似文献   

11.
A monoclonal antibody (IgM) against 5-methylcytosine (mC) was isolated and characterized. It showed a high specificity for mC with a cross-reactivity of less than 1% with cytosine and 0.1% with thymidine. An improved immunohybridization method, originally developed with polyclonal antibodies (Sano et al. (1980) Proc. Natl. Acad. Sci. USA 77, 3581), was applied to detect mC in immobilized DNA using the new monoclonal preparation. Human genomic DNA was cleaved with the restriction enzyme EcoRI and successively fractionated by malachite-green affinity chromatography and agarose gel electrophoresis. The fractionated DNA was transferred to nitrocellulose paper and treated with the anti-mC monoclonal antibody. Heavy methylation was observed in EcoRI-ladders of repetitive sequences of 1360, 1750, 2200 and 3400 bp, while 340, 660 and 2700 bp fragments were less methylated. The results show that methylation occurs in limited subsets of satellite II and III repetitive DNAs that contain high amounts of methylatable CpG dinucleotides, or CpG clusters.  相似文献   

12.
A poorly known acropomatid, Verilus sordidus Poey 1860, is redescribed based on six specimens from the western central Atlantic. We present diagnostic characters to differentiate this species from Neoscombrops atlanticus Mochizuki and Sano 1984, which has been confused with this species, and designate a neotype of V. sordidus. This species is distinguishable from N. atlanticus by the proximal-middle radial of the first anal-fin pterygiophore being slender with no trough or hollow on the anterodorsal portion (vs. hollow in N. atlanticus), several canine teeth posterior to the large canine teeth on either side of the symphysis of the lower jaw (vs. villiform teeth posterior to enlarged canines), and by the modal numbers of pectoral-fin rays, lateral-line scales, and gill rakers on the lower limb of the first arch.  相似文献   

13.
14.
Infectious pancreatic necrosis (IPN) is a disease of salmonid fishes. It has been reported in many countries throughout the world (M’Gonigle 1940, Wood et al. 1955, Besse & Kinkelin 1965, Vestergård Jørgensen & Bregnballe 1969, Sano 1971, Ball et al 1971, Ljungberg & Vestergård Jørgensen 1972, Schlotfeldt et al. 1975). Outbreaks of the disease can cause serious losses in populations of hatchery reared salmonids, the mortality rate varying between 10 and 90 % (Vestergård Jørgensen & Kehlet 1971). There are at least four different serotypes of the virus distinguished by neutralization tests (Wolf et al. 1968). Twenty-five isolates of IPN virus in Denmark proved to represent only two serotypes (Sp and Ab) (Vestergård Jørgensen & Kehlet). The present paper reports the first isolation of IPN virus from the stock at a fish farm in Norway.  相似文献   

15.

“Neurochemistry” in Japan was established by intensive cooperation between psychiatrists and their collaborators, biochemists, who have sought to investigate the etiology of mental illness to establish treatments. It was a completely different direction from the flow of modern biochemistry that was born using microorganisms or eukaryotic cells as research materials. Neurochemists aimed to elucidate the physiological or pathological functions of the brain through chemical analysis of the morphologically and functionally unique complexity and characteristics of brain. I here describe some of the origin and history of neurochemistry in Japan how researchers estabIished Japanese Society for Neurochemistry in1958 Yasuzo Tsukada as a president in collaboration with Isamu Sano, Genkichiro Takagaki and Masanori Kurokawa. The formation of research groups with the support of MEXT played a major role in promoting neurochemistry. Many international conferences held in Japan promoted the activity of neurochemistry: The International Society of Physiology (Tokyo) in 1965, and the Japan-US Neurochemistry Conference (Oiso) in 1965, and in 1967 the International Conference on Biochemistry (Tokyo). These meetings offered excitements to younger researchers by close interaction with the world top class researchers. Government established Brain Research Institutes in several national universities. The Asia–Pacific Society for Neurochemistry (APSN) was established in 1991 subsequent to an initiative by JSN. APSN presidents: Yasuzo Tsukada, Kazuhiro Ikenaka, and Akio Wanaka contributed to promote neurochemistry. The 4th ISN meeting was organized at Tokyo (Yasuzo Tsukada, president) in 1973 and the 15th ISN meeting at Kyoto (Kinya Kuriyama, president) in 1995. Kunihiko Suzuki and Kazuhiro Ikenaka as ISN Presidents greatly contributed in promoting the activity of ISN.

  相似文献   

16.
When maize seedlings were exposed to cold stress, a genome-wide demethylation occurred in root tissues. Screening of genomic DNA identified one particular fragment that was demethylated during chilling. This 1.8-kb fragment, designated ZmMI1, contained part of the coding region of a putative protein and part of a retrotransposon-like sequence. ZmMI1 was transcribed only under cold stress. Direct methylation mapping revealed that hypomethylated regions spanning 150 bases alternated with hypermethylated regions spanning 50 bases. Analysis of nuclear DNA digested with micrococcal nuclease indicated that these regions corresponded to nucleosome cores and linkers, respectively. Cold stress induced severe demethylation in core regions but left linker regions relatively intact. Thus, methylation and demethylation were periodic in nucleosomes. The following biological significance is conceivable. First, because DNA methylation in nucleosomes induces alteration of gene expression by changing chromatin structures, vast demethylation may serve as a common switch for many genes that are simultaneously controlled upon environmental cues. Second, because artificial demethylation induces heritable changes in plant phenotype (Sano, H., Kamada, I., Youssefian, S., Katsumi, M., and Wabilko, H. (1990) Mol. Gen. Genet. 220, 441-447), altered DNA methylation may result in epigenetic inheritance, in which gene expression is modified without changing the nucleotide sequence.  相似文献   

17.
We previously reported that STAT3 plays a crucial role in transducing a signal for migration of keratinocytes (Sano, S., Itami, S., Takeda, K., Tarutani, M., Yamaguchi, Y., Miura, H., Yoshikawa, K., Akira, S., and Takeda, J. (1999) EMBO J. 18, 4657-4668). To clarify the role of STAT3 in signaling the migration, we studied the intracellular signaling pathway through an integrin receptor in STAT3-deficient keratinocytes. STAT3-deficient keratinocytes demonstrated increased adhesiveness and fast spreading on a collagen matrix. Staining with anti-phosphotyrosine antibody revealed that STAT3-deficient keratinocytes had an increased number of tyrosyl-hyperphosphorylated focal adhesions. Analyses with immunoprecipitation revealed that p130(cas) was constitutively hyperphosphorylated on tyrosine residues, while other focal adhesion molecules such as focal adhesion kinase and paxillin were not. Transfection of STAT3-deficient keratinocytes with an adenoviral vector encoding the wild-type Stat3 gene reversed not only impaired migration but also the increased tyrosine phosphorylation of p130(cas). These results strongly suggest that STAT3 in keratinocytes plays a critical role in turnover of tyrosine phosphorylation of p130(cas), modulating cell adhesiveness to the substratum leading to growth factor-dependent cell migration.  相似文献   

18.
Multiscale computing is a challenging area even in biomechanics. Application of such a methodology to quantitatively compare postoperative hemodynamics in congenital heart diseases is very promising. In the treatment of hypoplastic left heart syndrome, which is a congenital heart disease where the left ventricle is missing or very small, the necessity to feed the pulmonary and systemic circulations is obtained with an interposition shunt. Two main options are available and differ from the sites of anastomoses: (i) the systemic-to-pulmonary conduit (Blalock-Taussig shunt known as the Norwood Operation (NO)) connecting the innominate artery (NO-BT) or the aorta (NO-CS) to the right pulmonary artery and (ii) the right ventricle to pulmonary artery shunt (known as Sano operation (SO)). The proposition that the SO is superior to the NO remains controversial. 3-D computer models of the NO (NO-BT and NO-CS) and SO were developed and investigated using the finite volume method. Conduits of 3, 3.5 and 4 mm were used in the NO models, whereas conduits of 4, 5 and 6 mm were used in the SO model. The hydraulic nets (lumped resistances, compliances, inertances and elastances) which represent the systemic, coronary and pulmonary circulations and the heart were identical in the two models. A multiscale approach was adopted to couple the 3-D models with the circulation net. Computer simulation results were compared with post-operative catheterization data. Results showed that (i) there is a good correlation between predicted and observed data: higher aortic diastolic pressure, decreased pulmonary arterial pressure, lower pulmonary-to-systemic flow ratio and higher coronary perfusion pressure in SO; (ii) there is a minimal regurgitant flow in the SO conduit. The close correlation between predicted and observed clinical data supports the use of mathematical modelling, with a mandatory multiscale approach, in the design and assessment of surgical procedures.  相似文献   

19.
Oryza glaberrima is an endemic African cultivated rice species. To provide a tool for evaluation and utilisation of the potential of O. glaberrima in rice breeding, we developed an interspecific O. glaberrima×Oryza sativa genetic linkage map. It was based on PCR markers, essentially microsatellites and STSs. Segregation of markers was examined in a backcross (O. sativa/O. glaberrima//O. sativa) population. Several traits were measured on the BC1 plants, and major genes and QTLs were mapped for these traits. Several of these genes correspond well to previously identified loci. The overall map length was comparable to those observed in indica×japonica crosses, indicating that recombination between the two species occurs without limitation. However, three chromosomes show discrepancies with the indica×japonica maps. The colinearity with intraspecific maps was very good, confirming previous cytological observations. A strong segregation-distortion hot spot was observed on chromosome 6 near the waxy gene, indicating the presence of s 10 , a sporo-gametophytic sterility gene previously identified by Sano (1990). The main interests of such a PCR-based map for African rice breeding are discussed, including gene and QTL localisation, marker-assisted selection, and the development of interspecific introgression lines. Received: 1 June 1991 / Accepted: 22 June 1999  相似文献   

20.
A versatile strategy has been developed for selectively and sequentially isolating targets in a liquid-phase affinity separation environment. The strategy uses a recently developed approach for joining together molecules in linkages that are defined by the complementary pairing of oligonucleotides conjugated to the different molecules [Niemeyer, C. M., Sano, T., Smith, C. L., and Cantor, C. R. (1994) Nucleic Acids Res. 22, 5530-9]. In the work presented here, streptavidin was noncovalently coupled with the temperature-responsive poly(N-isopropylacrylamide) [poly(NIPAAM)] through the sequence-specific hybridization of oligonucleotides conjugated to the protein and polymer. A 20-mer oligonucleotide was covalently linked through a heterobifunctional linker to a genetically engineered streptavidin variant that contained a unique cysteine residue at the solvent-accessible site Glu 116. The complementary DNA sequence was conjugated to the end of a linear ester-activated poly(NIPAAM). The two conjugates were allowed to self-assemble in solution via hybridization of their complementary DNA sequences. The streptavidin-poly(NIPAAM) complex could be used to affinity-precipitate radiolabeled biotin or biotinylated alkaline phosphatase above 32 degrees C through the thermally induced phase separation activity of the poly(NIPAAM). The streptavidin-oligo species could then be reversibly separated from the precipitated polymer-oligo conjugate and recycled by lowering the salt concentration, which results in denaturation of the short double-stranded DNA connection. The use of oligonucleotides to couple polymer to streptavidin allows for selective precipitation of different polymers and streptavidin complexes based on the sequence-specific hybridization of their oligonucleotide appendages.  相似文献   

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