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121.
Shigekazu Takahashi Haruna Yanai Yuko Oka-Takayama Aya Zanma-Sohtome Kosaku Fujiyama Akira Uchida Katsumi Nakayama Hiroyuki Satoh 《Planta》2013,238(6):1065-1080
Various plants possess non-photosynthetic, hydrophilic chlorophyll (Chl) proteins called water-soluble Chl-binding proteins (WSCPs). WSCPs are categorized into two classes; Class I (photoconvertible type) and Class II (non-photoconvertible type). Among Class II WSCPs, only Lepidium virginicum WSCP (LvWSCP) exhibits a low Chl a/b ratio compared with that found in the leaf. Although the physicochemical properties of LvWSCP have been characterized, its molecular properties have not yet been documented. Here, we report the characteristics of the LvWSCP gene, the biochemical properties of a recombinant LvWSCP, and the intracellular localization of LvWSCP. The cloned LvWSCP gene possesses a 669-bp open reading frame. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis revealed that the precursor of LvWSCP contains both N- and C-terminal extension peptides. RT-PCR analysis revealed that LvWSCP was transcribed in various tissues, with the levels being higher in developing tissues. A recombinant LvWSCP and hexa-histidine fusion protein (LvWSCP-His) could remove Chls from the thylakoid in aqueous solution and showed an absorption spectrum identical to that of native LvWSCP. Although LvWSCP-His could bind both Chl a and Chl b, it bound almost exclusively to Chl b when reconstituted in 40 % methanol. To clarify the intracellular targeting functions of the N- and C-terminal extension peptides, we constructed transgenic Arabidopsis thaliana lines expressing the Venus protein fused with the LvWSCP N- and/or C-terminal peptides, as well as Venus fused at the C-terminus of LvWSCP. The results showed that the N-terminal peptide functioned in ER body targeting, while the C-terminal sequence did not act as a trailer peptide. 相似文献
122.
Interleukin-21 (IL-21) is a pleiotropic cytokine that regulates T-cell, B-cell, NK-cell, and myeloid-cell functions. IL-21 binds with its cognate receptor complex, which consists of the IL-21 receptor (IL-21R) and the common gamma chain. We identified a novel IL-21R-binding molecule, WSB-1, which contains WD-40 repeats and a SOCS-box domain. WSB-1 associates with the middle part of intracytoplasmic region of IL-21R and enhances the maturation of IL-21R from N-linked glycosylated form to fully glycosylated mature form. Furthermore, WSB-1 moderates IL-21R degradation. Taken together, our present study suggests that WSB-1 has a role in the tuning of the maturation and degradation of IL-21R. 相似文献
123.
Mayo Yasugi Ritsuko Kubota-Koketsu Akifumi Yamashita Norihito Kawashita Anariwa Du Ryo Misaki Motoki Kuhara Naphatsawan Boonsathorn Kazuhito Fujiyama Yoshinobu Okuno Takaaki Nakaya Kazuyoshi Ikuta 《PloS one》2013,8(10)
The swine-origin pandemic A(H1N1)2009 virus, A(H1N1)pdm09, is still circulating in parts of the human population. To monitor variants that may escape from vaccination specificity, antigenic characterization of circulating viruses is important. In this study, a hybridoma clone producing human monoclonal antibody against A(H1N1)pdm09, designated 5E4, was prepared using peripheral lymphocytes from a vaccinated volunteer. The 5E4 showed viral neutralization activity and inhibited hemagglutination. 5E4 escape mutants harbored amino acid substitutions (A189T and D190E) in the hemagglutinin (HA) protein, suggesting that 5E4 recognized the antigenic site Sb in the HA protein. To study the diversity of Sb in A(H1N1)pdm09, 58 viral isolates were obtained during the 2009/10 and 2010/11 winter seasons in Osaka, Japan. Hemagglutination-inhibition titers were significantly reduced against 5E4 in the 2010/11 compared with the 2009/10 samples. Viral neutralizing titers were also significantly decreased in the 2010/11 samples. By contrast, isolated samples reacted well to ferret anti-A(H1N1)pdm09 serum from both seasons. Nonsynonymous substitution rates revealed that the variant Sb and Ca2 sequences were being positively selected between 2009/10 and 2010/11. In 7,415 HA protein sequences derived from GenBank, variants in the antigenic sites Sa and Sb increased significantly worldwide from 2009 to 2013. These results indicate that the antigenic variants in Sb are likely to be in global circulation currently. 相似文献
124.
Nonaka M Ma BY Imaeda H Kawabe K Kawasaki N Hodohara K Kawasaki N Andoh A Fujiyama Y Kawasaki T 《The Journal of biological chemistry》2011,286(25):22403-22413
Dendritic cell (DC)-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) is a type II transmembrane C-type lectin expressed on DCs such as myeloid DCs and monocyte-derived DCs (MoDCs). Recently, we have reported that DC-SIGN interacts with carcinoembryonic antigen (CEA) expressed on colorectal carcinoma cells. CEA is one of the most widely used tumor markers for gastrointestinal cancers such as colorectal cancer. On the other hand, other groups have reported that the level of Mac-2-binding protein (Mac-2BP) increases in patients with pancreatic, breast, and lung cancers, virus infections such as human immunodeficiency virus and hepatitis C virus, and autoimmune diseases. Here, we first identified Mac-2BP expressed on several colorectal carcinoma cell lines as a novel DC-SIGN ligand through affinity chromatography and mass spectrometry. Interestingly, we found that DC-SIGN selectively recognizes Mac-2BP derived from some colorectal carcinomas but not from the other ones. Furthermore, we found that the α1-3,4-fucose moieties of Le glycans expressed on DC-SIGN-binding Mac-2BP were important for recognition. DC-SIGN-dependent cellular interactions between immature MoDCs and colorectal carcinoma cells significantly inhibited MoDC functional maturation, suggesting that Mac-2BP may provide a tolerogenic microenvironment for colorectal carcinoma cells through DC-SIGN-dependent recognition. Importantly, Mac-2BP was detected as a predominant DC-SIGN ligand expressed on some primary colorectal cancer tissues from certain parts of patients in comparison with CEA from other parts, suggesting that DC-SIGN-binding Mac-2BP bearing tumor-associated Le glycans may become a novel potential colorectal cancer biomarker for some patients instead of CEA. 相似文献
125.
Masaoki Sasaki Yukio Kaneko Katsunori Oshita Hiroshi Takamatsu Yasuo Asao Tamotsu Yokotsuka 《Bioscience, biotechnology, and biochemistry》2013,77(9):1296-1300
Three isocoumarin compounds (BV 1, 2 and 3) were isolated from the cultural broth of Aspergillus oniki 1784. BV 1 was mellein (3-methyl-8-hydroxy-3,4-dihydroisocoumarin). BV 2 and 3 were assigned to be 3-methyl-4,8-dihydroxy-3,4-dihydroisocoumarin, 3-methyl-3,8-dihydroxy-3,4-dihydroisocoumarin, respectively. These two compounds (BV 2, 3) were newly isolated. Also another component named BV 4 was proved to be 6-methylsalicylic acid. 相似文献
126.
Daiki D. Horikawa John Cumbers Iori Sakakibara Dana Rogoff Stefan Leuko Raechel Harnoto Kazuharu Arakawa Toshiaki Katayama Takekazu Kunieda Atsushi Toyoda Asao Fujiyama Lynn J. Rothschild 《PloS one》2013,8(6)
Tardigrades inhabiting terrestrial environments exhibit extraordinary resistance to ionizing radiation and UV radiation although little is known about the mechanisms underlying the resistance. We found that the terrestrial tardigrade Ramazzottius varieornatus is able to tolerate massive doses of UVC irradiation by both being protected from forming UVC-induced thymine dimers in DNA in a desiccated, anhydrobiotic state as well as repairing the dimers that do form in the hydrated animals. In R. varieornatus accumulation of thymine dimers in DNA induced by irradiation with 2.5 kJ/m2 of UVC radiation disappeared 18 h after the exposure when the animals were exposed to fluorescent light but not in the dark. Much higher UV radiation tolerance was observed in desiccated anhydrobiotic R. varieornatus compared to hydrated specimens of this species. On the other hand, the freshwater tardigrade species Hypsibius dujardini that was used as control, showed much weaker tolerance to UVC radiation than R. varieornatus, and it did not contain a putative phrA gene sequence. The anhydrobiotes of R. varieornatus accumulated much less UVC-induced thymine dimers in DNA than hydrated one. It suggests that anhydrobiosis efficiently avoids DNA damage accumulation in R. varieornatus and confers better UV radiation tolerance on this species. Thus we propose that UV radiation tolerance in tardigrades is due to the both high capacities of DNA damage repair and DNA protection, a two-pronged survival strategy. 相似文献
127.
128.
Oxidative stress increases MICA and MICB gene expression in the human colon carcinoma cell line (CaCo-2) 总被引:9,自引:0,他引:9
The human major histocompatibility complex class I chain-related A gene (MICA) and the MICB gene are newly identified members of the major histocompatibility complex class I chain-related gene family. We demonstrate here that oxidative stress, induced by H(2)O(2), promoted MICA (2.2-fold) and MICB (3.8-fold) gene expression using the human colon carcinoma cell line (CaCo-2) and semi-quantitative RT-PCR. 相似文献
129.
130.
Hiro Sato Yoshiyuki Suzuki Munenori Ide Toshihide Katoh Shin-ei Noda Ken Ando Takahiro Oike Yuya Yoshimoto Noriyuki Okonogi Kousaku Mimura Takayuki Asao Hiroyuki Kuwano Takashi Nakano 《PloS one》2014,9(9)