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31.
Kazuya Hayashi Danji Fukushima Koya Mogi 《Bioscience, biotechnology, and biochemistry》2013,77(8):988-994
The molecular conformation of the alkaline proteinase of Aspergillus sojae in aqueous solution was investigated by the optical rotatory dispersion, Cotton effects, infra-red absorption spectra (amide I and V bands), ultraviolet difference spectra, etc. It is concluded that; (1) there are about 10 to 15% of the α-helix and a small amount of the β-structure in the enzyme molecule, but most parts of the peptide chain are present as the disordered structure; (2) the enzyme molecule is compactly folded even in the disordered parts; and (3) the two tryptophan residues involved in the peptide chain are burried in the interior of the molecule. 相似文献
32.
Ling Xu Megumi Kanasaki Jianhua He Munehiro Kitada Kenji Nagao Hiroko Jinzu Yasushi Noguchi Hiroshi Maegawa Keizo Kanasaki Daisuke Koya 《生物化学与生物物理学报:疾病的分子基础》2013,1832(10):1605-1612
Ketogenic amino acid (KAA) replacement diet has been shown to cure hepatic steatosis, a serious liver disease associated with diverse metabolic defects. In this study, we investigated the effects of KAA replacement diet on nutrition sensing signaling pathway and analyzed whether induction of hepatic autophagy was involved. Mice are fed with high fat diet (HFD) or KAA replacement in high-fat diet (30% fat in food; HFD)-fed (HFDKAAR) and sacrificed at 8, 12, 16 weeks after initiation of experimental food. Hepatic autophagy was analyzed in protein expression of several autophagy-associated molecules and in light chain-3 green fluorescent protein (LC-3 GFP) transgenic mice. HFDKAAR showed increased AMP-activated protein kinase (AMPK) phosphorylation and enhanced liver kinase B1 (LKB1) expression compared to control HFD-fed mice. The KAA-HFD-induced activation of AMPK was associated with an increased protein expression of sirtuin 1 (Sirt1), decreased forkhead box protein O3a (Foxo3a) level, and suppression of mammalian target of rapamycin (mTOR) phosphorylation compared with the HFD-fed mice. The intervention study revealed that a KAA-replacement diet also ameliorated all the established metabolic and autophagy defects in the HFD-fed mice, suggesting that a KAA-replacement diet can be used therapeutically in established diseases. These results indicate that KAA replacement in food could be a novel strategy to combat hepatic steatosis and metabolic abnormalities likely involvement of an induction of autophagy. 相似文献
33.
Yasunori Sugiyama Sho Yamashita Yuuki Uezato Yukako Senga Syouichi Katayama Naoki Goshima Yasushi Shigeri Noriyuki Sueyoshi Isamu Kameshita 《Analytical biochemistry》2016
To analyze a variety of protein phosphatases, we developed phosphorylated TandeMBP (P-TandeMBP), in which two different mouse myelin basic protein isoforms were fused in tandem, as a protein phosphatase substrate. P-TandeMBP was prepared efficiently in four steps: (1) phosphorylation of TandeMBP by a protein kinase mixture (Ca2+/calmodulin-dependent protein kinase Iδ, casein kinase 1δ, and extracellular signal-regulated kinase 2); (2) precipitation of both P-TandeMBP and protein kinases to remove ATP, Pi, and ADP; (3) acid extraction of P-TandeMBP with HCl to remove protein kinases; and (4) neutralization of the solution that contains P-TandeMBP with Tris. In combination with the malachite green assay, P-TandeMBP can be used to detect protein phosphatase activity without using radioactive materials. Moreover, P-TandeMBP served as an efficient substrate for PPM family phosphatases (PPM1A, PPM1B, PPM1D, PPM1F, PPM1G, PPM1H, PPM1K, and PPM1M) and PPP family phosphatase PP5. Various phosphatase activities were also detected with high sensitivity in gel filtration fractions from mouse brain using P-TandeMBP. These results indicate that P-TandeMBP might be a powerful tool for the detection of protein phosphatase activities. 相似文献
34.
Murakami Shinsuke Nakatani Jun Nakajima Kenichi Amasawa Eri Ii Ryota Hayashi Kiyotada Yoshikawa Naoki Daigo Ichiro Kishita Yusuke Ihara Tomohiko Shobatake Koichi Kudoh Yuki Motoshita Masaharu Kanemoto Keiichiro Hara Minako Kashiwagi Aiichiro Hashimoto Seiji Shigetomi Yosuke Kanzaki Masayuki Kikuchi Yasunori Ohno Hajime Fukushima Yasuhiro 《The International Journal of Life Cycle Assessment》2019,24(8):1544-1552
The International Journal of Life Cycle Assessment - 相似文献
35.
36.
Morita Y Araki H Sugimoto T Takeuchi K Yamane T Maeda T Yamamoto Y Nishi K Asano M Shirahama-Noda K Nishimura M Uzu T Hara-Nishimura I Koya D Kashiwagi A Ohkubo I 《FEBS letters》2007,581(7):1417-1424
Legumain/asparaginyl endopeptidase (EC 3.4.22.34) is a novel cysteine protease that is abundantly expressed in the late endosomes and lysosomes of renal proximal tubular cells. Recently, emerging evidence has indicated that legumain might play an important role in control of extracellular matrix turnover in various pathological conditions such as tumor growth/metastasis and progression of atherosclerosis. We initially found that purified legumain can directly degrade fibronectin, one of the main components of the extracellular matrix, in vitro. Therefore, we examined the effect of legumain on fibronectin degradation in cultured mouse renal proximal tubular cells. Fibronectin processing can be inhibited by chloroquine, an inhibitor of lysosomal degradation, and can be enhanced by the overexpression of legumain, indicating that fibronectin degradation occurs in the presence of legumain in lysosomes from renal proximal tubular cells. Furthermore, in legumain-deficient mice, unilateral ureteral obstruction (UUO)-induced renal interstitial protein accumulation of fibronectin and renal interstitial fibrosis were markedly enhanced. These findings indicate that legumain might have an important role in extracellular matrix remodeling via the degradation of fibronectin in renal proximal tubular cells. 相似文献
37.
38.
Yasunori Tome Tasuku Kiyuna Fuminari Uehara Michael Bouvet Hiroyuki Tsuchiya Fuminori Kanaya Robert M. Hoffman 《Journal of cellular biochemistry》2019,120(1):283-289
Human osteosarcoma 143B cells were previously stably transfected with an αv integrin green flourescent protein (GFP) vector. 143B cells expressing αv integrin-GFP were transplanted orthotopically in the tibia of transgenic nude mice ubiquitously expressing red fluorescent protein (RFP). The primary tumors acquired RFP-expressing stroma and were passaged orthotopically in the tibia in noncolored nude mice, which maintained the RFP stroma. The interaction of αv integrin-GFP expression in 143B cells with RFP-expressing host stromal cells was observed by confocal microscopy using the Olympus FV1000. Collagen fibers were imaged simultaneously in reflectance mode. The RFP-expressing stroma included cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) which persisted even 3 weeks after passage to nontransgenic nude mice. CAFs expressing RFP were aligned between collagen fibers and cancer cells expressing αv integrin-GFP. Six weeks after transplantation, pulmonary metastases expressing αv integrin-GFP could be identified. TAMs expressing RFP accompanied metastasized osteosarcoma cells expressing αv integrin-GFP in the lung. The current study demonstrates the importance of αv integrin interaction with stromal elements in osteosarcoma. 相似文献
39.
Shogo Tamura Masato Mukaide Yumi Katsuragi Wataru Fujii Koya Odaira Nobuaki Suzuki Nagaharu Tsukiji Shuichi Okamoto Atsuo Suzuki Takeshi Kanematsu Akira Katsumi Akira Takagi Katsuhide Ikeda Jun Ueyama Masaaki Hirayama Katsue Suzuki-Inoue Tadashi Matsushita Tetsuhito Kojima Fumihiko Hayakawa 《The Journal of biological chemistry》2022,298(5)
Bone marrow development and endochondral bone formation occur simultaneously. During endochondral ossification, periosteal vasculatures and stromal progenitors invade the primary avascular cartilaginous anlage, which induces primitive marrow development. We previously determined that bone marrow podoplanin (PDPN)-expressing stromal cells exist in the perivascular microenvironment and promote megakaryopoiesis and erythropoiesis. In this study, we aimed to examine the involvement of PDPN-expressing stromal cells in postnatal bone marrow generation. Using histological analysis, we observed that periosteum-derived PDPN-expressing stromal cells infiltrated the cartilaginous anlage of the postnatal epiphysis and populated on the primitive vasculature of secondary ossification center. Furthermore, immunophenotyping and cellular characteristic analyses indicated that the PDPN-expressing stromal cells constituted a subpopulation of the skeletal stem cell lineage. In vitro xenovascular model cocultured with human umbilical vein endothelial cells and PDPN-expressing skeletal stem cell progenies showed that PDPN-expressing stromal cells maintained vascular integrity via the release of angiogenic factors and vascular basement membrane-related extracellular matrices. We show that in this process, Notch signal activation committed the PDPN-expressing stromal cells into a dominant state with basement membrane-related extracellular matrices, especially type IV collagens. Our findings suggest that the PDPN-expressing stromal cells regulate the integrity of the primitive vasculatures in the epiphyseal nascent marrow. To the best of our knowledge, this is the first study to comprehensively examine how PDPN-expressing stromal cells contribute to marrow development and homeostasis. 相似文献