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61.
Diversity of Ca2+-induced morphology revealed by morphological phenotyping of Ca2+-sensitive mutants of Saccharomyces cerevisiae
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Yeast cell morphology can be treated as a quantitative trait using the image processing software CalMorph. In the present study, we investigated Ca(2+)-induced morphological changes in Ca(2+)-sensitive (cls) mutants of Saccharomyces cerevisiae, based on the discovery that the characteristic Ca(2+)-induced morphological changes in the Ca(2+)-sensitive mutant zds1 reflect changes in the Ca(2+) signaling-mediated cell cycle control pathway. By applying hierarchical cluster analysis to the quantitative morphological data of 58 cls mutants, 31 of these mutants were classified into seven classes based on morphological similarities. The patterns of morphological change induced by Ca(2+) in one class differed from those of another class. Based on the results obtained using versatile methods for phenotypic analysis, we conclude that a high concentration of Ca(2+) exerts a wide variety of effects on yeast and that there are multiple Ca(2+)-regulatory pathways that are distinct from the Zds1p-related pathway. 相似文献
62.
Morioka Shinsuke M. Phomikong Pisit Avakul Piyathap Jutagate Tuantong 《Ichthyological Research》2022,69(3):387-392
Ichthyological Research - Several morphometric characters with observing general morphology of laboratory-reared larval and juvenile Puntioplites proctozysron (9–40-day-old, 6.8 to... 相似文献
63.
Ando Shiori Funato Michinori Ohuchi Kazuki Inagaki Satoshi Sato Arisu Seki Junko Kawase Chizuru Saito Toshio Nishio Hisahide Nakamura Shinsuke Shimazawa Masamitsu Kaneko Hideo Hara Hideaki 《Neurochemical research》2019,44(7):1773-1779
Neurochemical Research - Spinal muscular atrophy (SMA) is an inherited disease characterized by progressive motor neuron death and subsequent muscle weakness and is caused by deletion or mutation... 相似文献
64.
Morikane K Tempero RM Sivinski CL Nomoto M Van Lith ML Muto T Hollingsworth MA 《Cancer immunology, immunotherapy : CII》1999,47(5):287-296
We established a model of orthotopic injection of a syngeneic pancreatic tumor cell line in C57BL/6 mice and evaluated the
effects of organ site on induction of immunity to a tumor-specific antigen, MUC1. Mice were challenged with a syngeneic pancreatic
adenocarcinoma cell line that expressed MUC1 (Panc02-MUC1) by orthotopic injection into the pancreas, or by subcutaneous injection.
Tumor cells injected into the pancreas grew much faster than those injected subcutaneously. Mice challenged subcutaneously
with Panc02-MUC1 rejected tumors or developed slowly growing tumors that were negative for MUC1 expression. In contrast, mice
challenged orthotopically into the pancreas developed progressive tumors that were positive for MUC1 expression. Sera from
mice that rejected Panc02-MUC1 (tumor-immune mice) showed no detectable IgG1 and IgM titers against the MUC1 tandem-repeat
peptide, whereas mice with progressive tumor growth had significant titers of IgG1 and IgM specific for MUC1. This suggests
that the humoral immune response was ineffective in mediating tumor rejection. The results show that the growth properties
and immunological rejection of pancreatic tumors is affected by the organ site at which the tumor grows.
Received: 25 April 1998 / Accepted: 7 October 1998 相似文献
65.
Six1 controls patterning of the mouse otic vesicle 总被引:3,自引:0,他引:3
Ozaki H Nakamura K Funahashi J Ikeda K Yamada G Tokano H Okamura HO Kitamura K Muto S Kotaki H Sudo K Horai R Iwakura Y Kawakami K 《Development (Cambridge, England)》2004,131(3):551-562
Six1 is a member of the Six family homeobox genes, which function as components of the Pax-Six-Eya-Dach gene network to control organ development. Six1 is expressed in otic vesicles, nasal epithelia, branchial arches/pouches, nephrogenic cords, somites and a limited set of ganglia. In this study, we established Six1-deficient mice and found that development of the inner ear, nose, thymus, kidney and skeletal muscle was severely affected. Six1-deficient embryos were devoid of inner ear structures, including cochlea and vestibule, while their endolymphatic sac was enlarged. The inner ear anomaly began at around E10.5 and Six1 was expressed in the ventral region of the otic vesicle in the wild-type embryos at this stage. In the otic vesicle of Six1-deficient embryos, expressions of Otx1, Otx2, Lfng and Fgf3, which were expressed ventrally in the wild-type otic vesicles, were abolished, while the expression domains of Dlx5, Hmx3, Dach1 and Dach2, which were expressed dorsally in the wild-type otic vesicles, expanded ventrally. Our results indicate that Six1 functions as a key regulator of otic vesicle patterning at early embryogenesis and controls the expression domains of downstream otic genes responsible for respective inner ear structures. In addition, cell proliferation was reduced and apoptotic cell death was enhanced in the ventral region of the otic vesicle, suggesting the involvement of Six1 in cell proliferation and survival. In spite of the similarity of otic phenotypes of Six1- and Shh-deficient mice, expressions of Six1 and Shh were mutually independent. 相似文献
66.
Ihh signaling is directly required for the osteoblast lineage in the endochondral skeleton 总被引:3,自引:0,他引:3
Long F Chung UI Ohba S McMahon J Kronenberg HM McMahon AP 《Development (Cambridge, England)》2004,131(6):1309-1318
Indian hedgehog (Ihh) is indispensable for development of the osteoblast lineage in the endochondral skeleton. In order to determine whether Ihh is directly required for osteoblast differentiation, we have genetically manipulated smoothened (Smo), which encodes a transmembrane protein that is essential for transducing all Hedgehog (Hh) signals. Removal of Smo from perichondrial cells by the Cre-LoxP approach prevents formation of a normal bone collar and also abolishes development of the primary spongiosa. Analysis of chimeric embryos composed of wild-type and Smo(n/n) cells indicates that Smo(n/n) cells fail to contribute to osteoblasts in either the bone collar or the primary spongiosa but generate ectopic chondrocytes. In order to assess whether Ihh is sufficient to induce bone formation in vivo, we have analyzed the bone collar in the long bones of embryos in which Ihh was artificially expressed in all chondrocytes by the UAS-GAL4 bigenic system. Although ectopic Ihh does not induce overt ossification along the entire cartilage anlage, it promotes progression of the bone collar toward the epiphysis, suggesting a synergistic effect between ectopic Ihh and endogenous factors such as the bone morphogenetic proteins (BMPs). In keeping with this model, Hh signaling is further found to be required in BMP-induced osteogenesis in cultures of a limb-bud cell line. Taken together, these results demonstrate that Ihh signaling is directly required for the osteoblast lineage in the developing long bones and that Ihh functions in conjunction with other factors such as BMPs to induce osteoblast differentiation. We suggest that Ihh acts in vivo on a potential progenitor cell to promote osteoblast and prevent chondrocyte differentiation. 相似文献
67.
Genetic variations at urotensin II and urotensin II receptor genes and risk of type 2 diabetes mellitus in Japanese 总被引:1,自引:0,他引:1
Suzuki S Wenyi Z Hirai M Hinokio Y Suzuki C Yamada T Yoshizumi S Suzuki M Tanizawa Y Matsutani A Oka Y 《Peptides》2004,25(10):1803-1808
Urotensin II is among the most potent vasoactive hormones known and the urotensin II (UTS2) gene is localized to 1p36-p32, one of the regions reported to show possible linkage with type 2 diabetes in Japanese. When we surveyed genetic polymorphisms in the UTS2 and urotensin II receptor (GPR14) gene, we identified two SNPs with amino acid substitutions (designated T21M and S89N and an SNP in the promotor region (-605G>A) of the UTS2 gene, and two SNPs in the non-coding region of the GPR14 gene. We then studied these three SNPs in the UTS2 gene and two SNPs in the GPR14 gene in 152 Japanese subjects with type 2 diabetes mellitus and two control Japanese populations. The allele frequency of 89N was significantly higher in type 2 diabetic patients than in both elderly normal subjects (P = 0.0018) and subjects with normal glucose tolerance (P = 0.0011), whereas the allele frequency of T21M and -605G>A in the UTS2 gene and those of two SNPs in the GPR14 gene were essentially identical in these three groups. Furthermore, in the subjects with normal glucose tolerance, 89N was associated with significantly higher insulin levels on oral glucose tolerance test, suggesting reduced insulin sensitivity in subjects with 89N. These results strongly suggest that subjects with S89N in the UTS2 gene are more insulin-resistant and thus more susceptible to type 2 diabetes mellitus development. 相似文献
68.
Tailed calix[4]resorcarene macrocycle (tail=undecyl) can be used as a platform to assemble four glycosaminoglycan polysaccharide chains to give a new type of proteoglycan mimics. A tetra(chondroitin sulfate) derivative thus obtained from the reaction of macrocyclic octaamine and chondroitin sulfate lactone is readily immobilized on a tissue culture plastic (polystyrene) plate and inhibits fibronectin-mediated adhesion of BHK (baby hamster kidney) cells thereon remarkably strongly with 50% inhibition occurring at a 10 ng/mL or 40 pM concentration range. 相似文献
69.
Ogino H Mimitsuka T Muto T Matsumura M Yasuda M Ishimi K Ishikawa H 《Journal of molecular microbiology and biotechnology》2004,7(4):212-223
A lipolytic enzyme gene (lip8) was cloned from organic solvent-tolerant Pseudomonas aeruginosa LST-03 and sequenced. In the sequenced nucleotides, an open reading frame consisting of 1,173 nucleotides and encoding 391 amino acids was found. Lip8 is considered to belong to the family VIII of lipolytic enzymes whose serine in the consensus sequence of -Ser-Xaa-Xaa-Lys- acts as catalytic nucleophile. The gene was expressed in Escherichia coli and purified by a combination of ammonium sulfate fractionation and hydrophobic interaction and ion-exchange chromatographies to homogeneity on SDS-PAGE analysis. The optimum temperature and heat stability of Lip8 were not as high as those of Lip3 and LST-03 lipase, two other lipolytic enzymes from the same strain. Addition of glycerol to a solution containing Lip8 stabilized this enzyme. By measuring the activities against various triacylglycerols and fatty acid methyl esters having carbon chains of different lengths, Lip8 was categorized as an esterase which has higher activities against fatty acid methyl esters with short-chain fatty acids. 相似文献
70.
Cady FM Muto DN Ciabeterri G Johns A Gainey Church K Wolff DJ 《Journal of the Association of Genetic Technologists》2004,30(3):77-81
Specific genetic abnormalities are of prognostic significance for patients with chronic lymphocytic leukemia (CLL) and multiple myeloma (MM); however, routine cytogenetic analysis usually provides normal results. We utilized two probe panels for interphase fluorescence in situ hybridization (FISH) studies to enhance the ability to detect genetic abnormalities in samples that were referred for routine cytogenetic studies for possible diagnoses of CLL or MM. The CLL panel consisted of probes for 11q22.3 (ATM gene), 13q14 (D13S319), the centromere of chromosome 12 (D12Z3) and 17p13.1 (P53 gene). The MM panel included probes for 14q32 (IgH gene) and/or t(11:14)(q13;q32) (BCL1/IgH), 13q14 (D13S319) and 17p13.1 (P53 gene). FISH detected clonal aberrations not identified by conventional cytogenetics in an additional 8 of 23 (35%) samples referred for possible CLL and 7 of 42 (17%) samples with possible MM. The prognostic significance of the aberrations identified ranged from favorable, to intermediate, to poor. Our studies indicate that many samples referred for routine cytogenetics testing for CLL and MM yield normal results for both conventional and FISH testing, likely due to lack of definitive diagnosis in a percentage of cases. However, FISH is more sensitive for the detection of clinically significant chromosome abnormalities and should be the testing methodology of choice for these disorders. 相似文献