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61.
62.
Accumulation of unfolded proteins in the endoplasmic reticulum (ER) causes ER stress. The ER stress sensor inositol requiring enzyme-1beta (IRE1β), which is specifically expressed in intestinal epithelial cells, is thought to be involved in translational repression. However, its mechanism of action is not fully understood. Using a reporter that can evaluate and distinguish between translation efficiency in the cytosol and on the ER membrane, we show here that IRE1β represses translation on the ER membrane but not in the cytosol, and that this selective repression depends on the RNase activity of IRE1β. 相似文献
63.
Naoko Kawamura 《Chromosoma》1979,74(2):179-188
Mosaic silkworms were induced when the hybrid eggs of two strains with different egg color and larval markings were exposed to low temperature. Cytological studies were conducted to find out the relation between mosaic larval pattern and ploidy in reproductive cells along with demonstration of chromosomes in the mosaic embryos. — Mosaic eggs eith the characters of both the father and the hybrid were two types, one with large serosa nuclei (LN-mosaic) and the other with small serosa nuclei (SN-mosaic). The cytological studies demonstrated that LN-mosaic individuals were 2n/4n, while SN-mosaic ones were n/2n. In both types of silkworms, cell ploidy level in nuclei of synkaryon origin was two times that of androgenic ones. — From the results obtained in the present studies as well as in the previous studies, a possible mechanism of induction of mosaicism in silkworms by cold shock is contemplated. 相似文献
64.
Kazuhiro Nakamura Yasuhiro Goto Naoko Yoshie Yoshio Inoue 《International journal of biological macromolecules》1992,14(6):321-325
It was found that an optically active copolyester, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), denoted as P(3HB-co-3HV), is synthesized by Alcaligenes eutrophus H16 from several amino acids under various fermentation conditions. The optimum condition for the biosynthesis from one amino acid, threonine, was investigated and its biosynthetic pathway was discussed on the basis of the relation between the fermentation condition and the co-monomer composition of the produced polyesters. 相似文献
65.
Kazuyuki Tanabe Toshihiro Mita Thibaut Jombart Anders Eriksson Shun Horibe Nirianne Palacpac Lisa Ranford-Cartwright Hiromi Sawai Naoko Sakihama Hiroshi Ohmae Masatoshi Nakamura Marcelo U. Ferreira Ananias A. Escalante Franck Prugnolle Anders Björkman Anna Färnert Akira Kaneko Toshihiro Horii Andrea Manica Hirohisa Kishino Francois Balloux 《Current biology : CB》2010,20(14):1283-1289
66.
67.
Harazono K Yamashita N Shinzato N Watanabe Y Fukatsu T Kurane R 《Bioscience, biotechnology, and biochemistry》2003,67(4):889-892
We isolated aromatics-degrading bacteria from the gut of a lower termite, Coptotermes formosanus, using a mineral salt medium containing various aromatic compounds as the sole carbon source. Two species, Burkholderia sp. strain VE22 and Citrobacter sp. strain VA53, were isolated by aerobic enrichment culture with veratraldehyde and vanillin, respectively. Strain VA53 could also grow and metabolize vanillin anaerobically. 相似文献
68.
Nozoye T Inoue H Takahashi M Ishimaru Y Nakanishi H Mori S Nishizawa NK 《Plant molecular biology》2007,64(1-2):35-47
To characterize Fe homeostasis during the early stages of seed germination, a microarray analysis was performed. mRNAs extracted
from fully mature seeds or seeds harvested 1–3 days after sowing were hybridized to a rice microarray containing approximately
22,000 cDNA oligo probes. Many Fe deficiency-inducible genes were strongly expressed throughout early seed germination. These
results suggest that the demand for Fe is extremely high during germination.
Under Fe-deficient conditions, rice produces and secretes a metal-cation chelator called deoxymugineic acid (DMA) to acquire
Fe from the soil. In addition, DMA and its intermediate nicotianamine (NA) are thought to be involved in long distance Fe
transport in rice. Using promoter-β-glucuronidase (GUS) analysis, we investigated the expression patterns during seed germination
of the Fe deficiency-inducible genes OsNAS1, OsNAS2, OsNAS3, OsNAAT1, and OsDMAS1, which encode enzymes that participate in the biosynthesis of DMA, and the transporter genes OsYSL2 and OsIRT1, which are involved in Fe transport. All of these genes were expressed in germinating seeds prior to protrusion of the radicle.
These results suggest that DMA and NA are produced and involved in Fe transport during germination.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
69.
Adrenomedullin is an autocrine/paracrine growth factor for rat vascular smooth muscle cells 总被引:4,自引:0,他引:4
Adrenomedullin is a potent vasodilator peptide secreted by vascular endothelial and smooth muscle cells. Adrenomedullin stimulates the proliferation of quiescent rat vascular smooth muscle cells (VSMCs) via p42/p44 ERK/MAP kinase activation. Recently, receptor-activity-modifying proteins (RAMPs) have been shown to transport calcitonin-receptor-like-receptor (CRLR) to the cell surface to present either as CGRP receptor or adrenomedullin receptor. We investigated whether adrenomedullin acts as an autocrine/paracrine growth factor for cultured rat VSMCs and whether coexpressions of RAMP isoform and CRLR may mediate p42/p44 ERK/MAP kinase activation by adrenomedullin. Adrenomedullin dose-dependently stimulated the proliferation of quiescent rat VSMCs, and this effect was inhibited by an adrenomedullin receptor antagonist, a MAP kinase kinase inhibitor and phosphatidylinositol 3-kinase inhibitors. Addition of either CGRP(8-37) or anti-adrenomedullin antibody to exponentially growing rat VSMCs inhibited the serum-induced cell proliferation, suggesting its role as an autocrine/paracrine growth factor. Cotransfection of RAMP2 or RAMP3 with CRLR into rat VSMCs potentiated activation of cAMP activity, but not of p42/p44 ERK/MAP kinase activity in response to adrenomedullin. Our results suggest that adrenomedullin is an autocrine/paracrine growth factor for rat VSMCs via p42/p44 ERK/MAP kinase and phosphatidylinositol 3-kinase pathways and that it is not mediated by human RAMP-CRLR receptors. 相似文献
70.
Chijiwa T Hamai S Tsubouchi S Ogawa T Deshimaru M Oda-Ueda N Hattori S Kihara H Tsunasawa S Ohno M 《Journal of molecular evolution》2003,57(5):546-554
Trimeresurus flavoviridis (Crotalinae) snakes inhabit the southwestern islands of Japan: Amami-Oshima, Tokunoshima, and Okinawa. Affinity and conventional chromatographies of Amami-Oshima T. flavoviridis venom led to isolation of a novel phospholipase A2 (PLA2). This protein was highly homologous (91%) in sequence to trimucrotoxin, a neurotoxic PLA2, which had been isolated from T. mucrosquamatus (Taiwan) venom, and exhibited weak neurotoxicity. This protein was named PLA-N. Its LD50 for mice was 1.34 µg/g, which is comparable to that of trimucrotoxin. The cDNA encoding PLA-N was isolated from both the Amami-Oshima and the Tokunoshima T. flavoviridis venom-gland cDNA libraries. Screening of the Okinawa T. flavoviridis venom-gland cDNA library with PLA-N cDNA led to isolation of the cDNA encoding one amino acid-substituted PLA-N homologue, named PLA-N(O), suggesting that interisland mutation occurred and that Okinawa island was separated from a former island prior to dissociation of Amami-Oshima and Tokunoshima islands. Construction of a phylogenetic tree of Crotalinae venom group II PLA2s based on the amino acid sequences revealed that neurotoxic PLA2s including PLA-N and PLA-N(O) form an independent cluster which is distant from other PLA2 groups such as PLA2 type, basic [Asp49]PLA2 type, and [Lys49]PLA2 type. Comparison of the nucleotide sequence of PLA-N cDNA with those of the cDNAs encoding other T. flavoviridis venom PLA2s showed that they have evolved in an accelerated manner. However, when comparison was made within the cDNAs encoding Crotalinae venom neurotoxic PLA2s, their evolutionary rates appear to be reduced to a level between accelerated evolution and neutral evolution. It is likely that ancestral genes of neurotoxic PLA2s evolved in an accelerated manner until they had acquired neurotoxic function and since then they have evolved with less frequent mutation, possibly for functional conservation.
The nucleotide sequences reported in this paper are available from the GenBank/EMBL/DDBJ databases under accession numbers AB102728 and AB102729. 相似文献