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941.
Sakai K Nakamura T Suzuki Y Imizu T Matsumoto K 《Biochemical and biophysical research communications》2011,412(1):98-103
Matrix metalloproteinases (MMPs) play roles in spatially dynamic processes, including morphogenesis, wound healing, and tumor invasion. Three-dimensional (3-D) type I collagen stimulates cellular activation of MMP-2, however, the mechanisms underlying this are controversial. The present study investigated mechanisms for 3-D collagen-induced MMP-2 activation in highly invasive human malignant mesothelioma cells. MMP-2 was effectively activated by cells cultured in 3-D collagen but not in 2-D collagen, whereas MMP-2 activation was not regulated by the flexibility of collagen. The 3-D collagen did not largely increase the gene expression of MMP-2 and MT1-MMP. However, MT1-MMP exposed to the cell surface was much increased by 3-D collagen, and loss of MT1-MMP abolished MMP-2 activation in response to 3-D collagen. MT1-MMP and integrin β1 translocated to pericellular regions interacting with collagen-coated microbeads, however their localization was different. Importantly, inhibition of integrin β1 function and expression did not affect 3-D collagen-induced cell surface localization of MT1-MMP and MMP-2 activation. Our results strongly suggest that 3-D collagen scaffolding may provide opportunity for direct and multivalent interaction with MT1-MMP, by which MMP-2 activation occur in abundant cell surface MT1-MMP-dependent manner, rather than a manner regulated by matrix stiffness and integrin β1 function. 相似文献
942.
Oe K Ueha T Sakai Y Niikura T Lee SY Koh A Hasegawa T Tanaka M Miwa M Kurosaka M 《Biochemical and biophysical research communications》2011,(1):148-152
Quasispecies is a remarkable characteristic of hepatitis C virus (HCV) and has profound roles in HCV biology and clinical practice. The understanding of HCV quasispecies behavior, in particular in acute HCV infection, is valuable for vaccine development and therapeutic interference. However, acute HCV infection is seldom encountered in clinic practice due to its silent onset. In the present study, we reported a unique case of de novo HCV infection associated with the transplantation of bone marrow from a HCV-positive donor. HCV quasispecies diversity was determined in both the donor and the recipient over a 4-year follow-up, accompanied with simultaneous measurement of HCV neutralizing antibody. Detailed genetic and phylogenetic analyses revealed a divergent quasispecies evolution, which was not related to dynamic changes of HCV neutralizing antibody. Instead, our data suggested an essential role of the fitness adaptation of founder viral population in driving such an evolutionary pattern. 相似文献
943.
Fujimoto T Machida T Tsunoda T Doi K Ota T Kuroki M Shirasawa S 《Biochemical and biophysical research communications》2011,(2):282-286
Concanavalin A (ConA), a Ca2+/Mn2+-dependent and mannose/glucose-binding legume lectin, has drawn a rising attention for its remarkable anti-proliferative and anti-tumor activities to a variety of cancer cells. ConA induces programmed cell death via mitochondria-mediated, P73-Foxo1a-Bim apoptosis and BNIP3-mediated mitochondrial autophagy. Through IKK-NF-κB-COX-2, SHP-2-MEK-1-ERK, and SHP-2-Ras-ERK anti-angiogenic pathways, ConA would inhibit cancer cell survival. In addition, ConA stimulates cell immunity and generates an immune memory, resisting to the same genotypic tumor. These biological findings shed light on new perspectives of ConA as a potential anti-neoplastic agent targeting apoptosis, autophagy and anti-angiogenesis in pre-clinical or clinical trials for cancer therapeutics. 相似文献
944.
Fujimoto T Machida T Tanaka Y Tsunoda T Doi K Ota T Okamura T Kuroki M Shirasawa S 《Biochemical and biophysical research communications》2011,(2):214-443
Three inositol 1,4,5-trisphosphate receptor (IP3R) subtypes are differentially expressed among tissues and function as the Ca2+ release channel on specialized endoplasmic reticulum (ER) membranes. The proper subcellular localization of IP3R is crucial for its proper function, but this molecular mechanism is unclear. KRAS-induced actin-interacting protein (KRAP) was originally identified as a cancer-related molecule, and is involved in the regulation of whole-body energy homeostasis and pancreatic exocrine system. We herein identified IP3R as an associated molecule with KRAP in vivo, and the association was validated by the co-immunoprecipitation and confocal immunostaining studies in mouse tissues including liver and pancreas. The association of KRAP with IP3R was also observed in the human epithelial cell lines including HCT116, HeLa and HEK293 cells. Intriguingly, KRAP interacts with distinct subtypes of IP3R in a tissue-dependent manner, i.e. IP3R1 and IP3R2 in the liver and IP3R2 and IP3R3 in the pancreas. The NH2-terminal amino acid residues 1–610 of IP3R are critical for the association with KRAP and KRAP–IP3R complex resides in a specialized ER but not a typical reticular ER. Furthermore, the localization of particular IP3R subtypes in tissues from KRAP-deficient mice is obviously disturbed, i.e. IP3R1 and IP3R2 in the liver and IP3R2 and IP3R3 in the pancreas. These findings demonstrate that KRAP physically associates with IP3R and regulates the proper localization of IP3R in the epithelial cells in vivo and cultured cells, and might shed light on the Ca2+ signaling underlying physiological cellular programs, cancer development and metabolism-related diseases. 相似文献
945.
946.
Keisuke Oe Takeshi Ueha Yoshitada Sakai Takahiro Niikura Sang Yang Lee Akihiro Koh Takumi Hasegawa Masaya Tanaka Masahiko Miwa Masahiro Kurosaka 《Biochemical and biophysical research communications》2011,407(1):148
In Europe, carbon dioxide therapy has been used for cardiac disease and skin problems for a long time. However there have been few reports investigating the effects of carbon dioxide therapy on skeletal muscle. Peroxisome proliferators-activated receptor (PPAR)-gamma coactivator-1 (PGC-1α) is up-regulated as a result of exercise and mediates known responses to exercise, such as mitochondrial biogenesis and muscle fiber-type switching, and neovascularization via up-regulation of vascular endothelial growth factor (VEGF). It is also known that silent mating type information regulation 2 homologs 1 (SIRT1) enhances PGC-1α-mediated muscle fiber-type switching. Previously, we demonstrated transcutaneous application of CO2 increased blood flow and a partial increase of O2 pressure in the local tissue known as the Bohr effect. In this study, we transcutaneously applied CO2 to the lower limbs of rats, and investigated the effect on the fast muscle, tibialis anterior (TA) muscle. The transcutaneous CO2 application caused: (1) the gene expression of PGC-1α, silent mating type information regulation 2 homologs 1 (SIRT1) and VEGF, and increased the number of mitochondria, as proven by real-time PCR and immunohistochemistry, (2) muscle fiber switching in the TA muscle, as proven by isolation of myosin heavy chain and ATPase staining. Our results suggest the transcutaneous application of CO2 may have therapeutic potential for muscular strength recovery resulting from disuse atrophy in post-operative patients and the elderly population. 相似文献
947.
Miyamura N Nakamura T Goto-Inoue N Zaima N Hayasaka T Yamasaki T Terai S Sakaida I Setou M Nishina H 《Biochemical and biophysical research communications》2011,408(1):120-125
After partial hepatectomy (PH), regenerating liver accumulates unknown lipid species. Here, we analyzed lipids in murine liver and adipose tissues following PH by thin-layer chromatography (TLC), imaging mass spectrometry (IMS), and real-time RT-PCR. In liver, IMS revealed that a single TLC band comprised major 19 TG species. Similarly, IMS showed a single phospholipid TLC band to be major 13 species. In adipose tissues, PH induced changes to expression of genes regulating lipid metabolism. Finally, IMS of phosphatidylcholine species demonstrated distribution gradients in lobules that resembled hepatic zonation. IMS is thus a novel and power tool for analyzing lipid species with high resolution. 相似文献
948.
Utsuno H Asami T Van Dooren TJ Gittenberger E 《Evolution; international journal of organic evolution》2011,65(8):2399-2411
Among metazoan species, left-right reversals in primary asymmetry have rarely gone to fixation. This suggests that a general mechanism suppresses the evolution of polarity reversal. Most metazoans appear externally symmetric and reproduce by external fertilization or copulation with genitalia located in the midline. Thus, reversal should generate little exogenous disadvantage when interacting with the external environment or in mating with the common wild-type. Accordingly, an endogenously caused fitness reduction may be responsible for the general absence of reversed species. However, how this selection operates is little understood. Phenotypic changes associated with reversal are usually inseparable from zygotic pleiotropy. By exploiting hermaphroditism and the maternal inheritance of left-right polarity, we generated dextral and sinistral snails that share the same zygotic genotype. Before hatching, these sinistrals developed lethal morphological anomalies more frequently than dextrals. Their shell shape at maturity differed from the mirror image of the dextral shell. These interchiral differences demonstrate pleiotropy in maternal effects of the polarity or linked genes. Variation in interchiral differences between parental crosses suggests the presence of epistatic variation in relative performance of sinistrals. Our results show that internal selection operates against polarity reversal, and we suggest that this is due to changes in blastomere configuration. 相似文献
949.
Shuhei Ota Haruyo Yamaguchi Faustine Vanel Shigeshi Fuchida Hiroshi Koshikawa Takahiro Yamagishi Hiroshi Yamamoto Masanobu Kawachi 《Phycological Research》2020,68(1):41-49
Seafloor massive sulfide (SMS) deposits are the target of available metallic resources. The toxic impacts of leachable metals from hydrothermal ore by mining operations in marine environments are a concern. However, ecotoxicological knowledge about marine algae, and particularly open ocean species, is still limited. Here, we evaluated the toxic effects of three leachable metals (i.e. Zn, Cu, and Pb) on seven marine algae, including cyanobacteria and eukaryotes, by a delayed fluorescence method. Cyanobacterial Synechococcus and Cyanobium species were sensitive to Zn and Cu, while eukaryotic algae showed various responses to heavy metal species. The prasinophycean Bathycoccus prasinos NIES‐2670 was sensitive to all metal species; this strain is a potential test strain to detect the leachable metals. A co‐culture experiment showed that the impact on community structure varies depending on leachable metal species. This study demonstrates that surveys across multiple taxonomic groups are necessary to assess the impact of SMS‐mining operations on marine ecosystems as a whole. 相似文献
950.
Akihiro Kusumi Takahiro K. Fujiwara Taka A. Tsunoyama Rinshi S. Kasai An‐An Liu Koichiro M. Hirosawa Masanao Kinoshita Nobuaki Matsumori Naoko Komura Hiromune Ando Kenichi G. N. Suzuki 《Traffic (Copenhagen, Denmark)》2020,21(1):106-137
Many plasma membrane (PM) functions depend on the cholesterol concentration in the PM in strikingly nonlinear, cooperative ways: fully functional in the presence of physiological cholesterol levels (35~45 mol%), and nonfunctional below 25 mol% cholesterol; namely, still in the presence of high concentrations of cholesterol. This suggests the involvement of cholesterol‐based complexes/domains formed cooperatively. In this review, by examining the results obtained by using fluorescent lipid analogs and avoiding the trap of circular logic, often found in the raft literature, we point out the fundamental similarities of liquid‐ordered (Lo)‐phase domains in giant unilamellar vesicles, Lo‐phase‐like domains formed at lower temperatures in giant PM vesicles, and detergent‐resistant membranes: these domains are formed by cooperative interactions of cholesterol, saturated acyl chains, and unsaturated acyl chains, in the presence of >25 mol% cholesterol. The literature contains evidence, indicating that the domains formed by the same basic cooperative molecular interactions exist and play essential roles in signal transduction in the PM. Therefore, as a working definition, we propose that raft domains in the PM are liquid‐like molecular complexes/domains formed by cooperative interactions of cholesterol with saturated acyl chains as well as unsaturated acyl chains, due to saturated acyl chains' weak multiple accommodating interactions with cholesterol and cholesterol's low miscibility with unsaturated acyl chains and TM proteins. Molecules move within raft domains and exchange with those in the bulk PM. We provide a logically established collection of fluorescent lipid probes that preferentially partition into raft and non‐raft domains, as defined here, in the PM. 相似文献