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排序方式: 共有7404条查询结果,搜索用时 15 毫秒
31.
32.
Funaki M Benincasa K Randhawa PK 《Biochemical and biophysical research communications》2007,360(4):891-896
Insulin-stimulated GLUT4 recruitment to the plasma membrane is impaired in insulin resistance. We recently reported that a cell permeable phosphoinositide-binding peptide induces GLUT4 recruitment as potently as insulin, but does not activate GLUT4 to initiate glucose uptake. Here we investigated whether the peptide-induced GLUT4 recruitment is intact in insulin resistance. The expression levels of GLUT1 and GLUT4 were unaffected by chronically treating 3T3-L1 adipocytes with insulin. GLUT4 recruitment by acute insulin stimulation after chronic insulin treatment was significantly reduced, but was fully restored by the peptide treatment. However, subsequent acute insulin stimulation to activate GLUT4 failed to increase glucose uptake in peptide-pretreated cells. Insulin-stimulated GLUT1 recruitment was unaffected by the peptide pretreatment. These results suggest that the GLUT4 recruitment signal caused by the peptide is intact in insulin resistance, but GLUT4 activation that occurs subsequent to recruitment is not rescued by the peptide treatment. 相似文献
33.
Kazuo Imai Norihito Tarumoto Kiyoko Amo Makoto Takahashi Naoya Sakamoto Atsushi Kosaka Yasuyuki Kato Kei Mikita Jun Sakai Takashi Murakami Yutaka Suzuki Shigefumi Maesaki Takuya Maeda 《Parasitology international》2018,67(1):34-37
Cutaneous leishmaniasis (CL) is gaining attention as a public health problem. We present two cases of CL imported from Syria and Venezuela in Japan. We diagnosed them as CL non-invasively by the direct boil loop-mediated isothermal amplification method and an innovative sequencing method using the MinION? sequencer. This report demonstrates that our procedure could be useful for the diagnosis of CL in both clinical and epidemiological settings. 相似文献
34.
35.
Tsuyoshi Kenri Yoshito Kawakita Hisashi Kudo U. Matsumoto Shigetarou Mori Yukio Furukawa Yuhei O. Tahara Keigo Shibayama Yuuki Hayashi Munehito Arai Makoto Miyata 《Biochemical and biophysical research communications》2019,508(4):1050-1055
Mycoplasma pneumoniae forms an attachment organelle at one cell pole, binds to the host cell surface, and glides via a unique mechanism. A 170-kDa protein, P1 adhesin, present on the organelle surface plays a critical role in the binding and gliding process. In this study, we obtained a recombinant P1 adhesin comprising 1476 amino acid residues, excluding the C-terminal domain of 109 amino acids that carried the transmembrane segment, that were fused to additional 17 amino acid residues carrying a hexa-histidine (6?×?His) tag using an Escherichia coli expression system. The recombinant protein showed solubility, and chirality in circular dichroism (CD). The results of analytical gel filtration, ultracentrifugation, negative-staining electron microscopy, and small-angle X-ray scattering (SAXS) showed that the recombinant protein exists in a monomeric form with a uniformly folded structure. SAXS analysis suggested the presence of a compact and ellipsoidal structure rather than random or molten globule-like conformation. Structure model based on SAXS results fitted well with the corresponding structure obtained with cryo-electron tomography from a closely related species, M. genitalium. This recombinant protein may be useful for structural and functional studies as well as for the preparation of antibodies for medical applications. 相似文献
36.
Lanying Zhao Hirotomo Saitsu Xiangnan Sun Kohei Shiota Makoto Ishibashi 《Mechanisms of development》2010,127(1-2):62-72
Accumulating evidence suggests that Sonic hedgehog (Shh) signaling plays a crucial role in eye vesicle patterning in vertebrates. Shh promotes expression of Pax2 in the optic stalk and represses expression of Pax6 in the optic cup. Shh signaling contributes to establishment of both proximal–distal and dorsal–ventral axes by activating Vax1, Vax2, and Pax2. In the dorsal part of the developing retina, Bmp4 is expressed and antagonizes the ventralizing effects of Shh signaling through the activation of Tbx5 expression in chick and Xenopus. To examine the roles of Shh signaling in optic cup formation and optic stalk development, we utilized the Smoothened (Smo) conditional knockout (CKO) mouse line. Smo is a membrane protein which mediates Shh signaling into inside of cells. Cre expression was driven by Fgf15 enhancer. The ventral evagination of the optic cup deteriorated from E10 in the Smo-CKO, whereas the dorsal optic cup and optic stalk develop normally until E11. We analyzed expression of various genes such as Pax family (Pax2/Pax6), Vax family (Vax1/Vax2) and Bmp4. Bmp4 expression was greatly upregulated in the optic vesicle by the 21-somite stage. Then Vax1/2 expression was decreased at the 20- to 24-somite stages. Pax2/6 expression was affected at the 27- to 32-somite stages. Our data suggest that the effects of the absence of Shh signaling on Vax1/Vax2 are mediated through increased Bmp4 expression throughout the optic cup. Also unchanged patterns of Raldh2 and Raldh3 suggest that retinoic acid is not the downstream to Shh signaling to control the ventral optic cup morphology. 相似文献
37.
Takako S. Kaneko Mamiko Sato Masako Osumi Makoto Muroi Akira Takatsuki 《Plant cell reports》1996,15(6):409-413
Summary The effects of brefeldin A (BFA) on the secretion of acid phosphatase (APase) by tobacco protoplasts were investigated. Secretion of APase was inhibited by BFA in a dose-dependent manner, with a concomitant intracellular accumulation of the enzyme. The secreted APase was composed of two isoforms. BFA (10/ g/ml) inhibited the secretion of one of the isoforms without inhibiting that of the other, and this phenomenon explains the partial inhibition of APase secretion as a whole. The inhibition of APase secretion was accompanied by changes in the morphology of the Golgi apparatus and also by an increment in massdensity of cells.Abbreviations APase
acid phosphatase
- BFA
brefeldin A
- CHX
cycloheximide
- PAGE
polyacrylamide gel electrophoresis 相似文献
38.
Goldar MM Nishie T Ishikura Y Fukuda T Takegawa K Kawamukai M 《Bioscience, biotechnology, and biochemistry》2005,69(7):1422-1426
The moc1/sds23 gene was isolated to induce sexual development of a sterile strain due to overexpression of adenylate cyclase in Schizosaccharomyces pombe. Here, we studied the functional conservation between moc1/sds23 and its two orthologs SDS23 and SDS24 in Saccharomyces cerevisiae. We observed that the temperature sensitivity, salt tolerance, cell morphology, and sterility of the Deltamoc1 mutant in S. pombe were recovered by expressing either S. cerevisiae SDS23 or SDS24. We found that deletion of both SDS23 and SDS24 resulted in the production of a large vacuole that was reversed by the expression of S. pombe moc1/sds23. In these ways we found that S. pombe Moc1/Sds23 and S. cerevisiae SDS23p or SDS24p are functional homologs. In addition we found that the Deltasds23 Deltasds24 diploid strain reduces cell separation in forming pseudohyphal-like growth in S. cerevisiae. Thus S. pombe moc1/sds23 and S. cerevisiae SDS23 or SDS24 are interchangeable with each other, but their disruptants are phenotypically dissimilar. 相似文献
39.
Seiya Oura Toshiaki Hino Takashi Satoh Taichi Noda Takayuki Koyano Ayako Isotani Makoto Matsuyama Shizuo Akira Kei-ichiro Ishiguro Masahito Ikawa 《PLoS genetics》2022,18(6)
Meiosis is a hallmark event in germ cell development that accompanies sequential events executed by numerous molecules. Therefore, characterization of these factors is one of the best strategies to clarify the mechanism of meiosis. Here, we report tripartite motif-containing 41 (TRIM41), a ubiquitin ligase E3, as an essential factor for proper meiotic progression and fertility in male mice. Trim41 knockout (KO) spermatocytes exhibited synaptonemal complex protein 3 (SYCP3) overloading, especially on the X chromosome. Furthermore, mutant mice lacking the RING domain of TRIM41, required for the ubiquitin ligase E3 activity, phenocopied Trim41 KO mice. We then examined the behavior of mutant TRIM41 (ΔRING-TRIM41) and found that ΔRING-TRIM41 accumulated on the chromosome axes with overloaded SYCP3. This result suggested that TRIM41 exerts its function on the chromosome axes. Our study revealed that Trim41 is essential for preventing SYCP3 overloading, suggesting a TRIM41-mediated mechanism for regulating chromosome axis protein dynamics during male meiotic progression. 相似文献
40.
Sasado T Morinaga C Niwa K Shinomiya A Yasuoka A Suwa H Hirose Y Yoda H Henrich T Deguchi T Iwanami N Watanabe T Kunimatsu S Osakada M Okamoto Y Kota Y Yamanaka T Tanaka M Kondoh H Furutani-Seiki M 《Mechanisms of development》2004,121(7-8):817-828
The development of germ cells has been intensively studied in Medaka (Oryzias latipes). We have undertaken a large-scale screen to identify mutations affecting the development of primordial germ cells (PGCs) in Medaka. Embryos derived from mutagenized founder fish were screened for an abnormal distribution or number of PGCs at embryonic stage 27 by RNA in situ hybridization for the Medaka vasa homologue (olvas). At this stage, PGCs coalesce into two bilateral vasa-expressing foci in the ventrolateral regions of the trunk after their migration and group organization. Nineteen mutations were identified from a screen corresponding to 450 mutagenized haploid genomes. Eleven of the mutations caused altered PGC distribution. Most of these alterations were associated with morphological abnormalities and could be grouped into four phenotypic classes: Class 1, PGCs dispersed into bilateral lines; Class 2, PGCs dispersed in a region more medial than that in Class 1; Class 3, PGCs scattered laterally and over the yolk sac area; and Class 4, PGCs clustered in a single median focus. Eight mutations caused a decrease in the number of PGCs. This decrease was observed in the offspring of heterozygous mothers, indicating the contribution of a maternal factor in determining PGC abundance. Taken together, these mutations should prove useful in identifying molecular mechanisms underlying the early PGC development and migration. 相似文献