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971.
Saeko Katoh Shingo Kaneko Yuji Isagi Noriaki Murakami Hidetoshi Kato 《Conservation Genetics》2007,8(6):1487-1490
Twelve microsatellite loci were isolated and characterized for Melicope quadrilocularis, an insular endemic tree species of the Bonin Islands. The observed number of alleles at each locus ranged from 1 to 18.
The range of expected heterozygosity was 0.0000–0.9445. The inter-specific applicability of these loci was evaluated by analyzing
two other endemic species and one endemic variety of Melicope that are also distributed on the Bonin Islands. All primer pairs for the 12 loci tested successfully amplified the loci in
all taxa, except for primers for four loci in M. nishimurae. 相似文献
972.
Metrosideros boninensis is an endangered endemic plant species from the Bonin Islands. We isolated and characterized nine microsatellite loci in
this species. The expected heterozygosities of these nine markers ranged from 0.127 to 0.768. These markers described here
will be useful for investigating the genetic diversity, genetic structure and gene flow, and planning for conservation of
M. boninensis. 相似文献
973.
Shimoda K Kwon S Utsuki A Ohiwa S Katsuragi H Yonemoto N Hamada H Hamada H 《Phytochemistry》2007,68(10):1391-1396
The glycosylation of capsaicin and 8-nordihydrocapsaicin was investigated using cultured cells of Catharanthus roseus. In addition to capsaicin 4-O-beta-d-glucopyranoside (170 microg/g fr. wt of cells), the biotransformation products, capsaicin 4-O-(6-O-beta-D-xylopyranosyl)-beta-D-glucopyranoside (116 microg/g fr. wt of cells) and capsaicin 4-O-(6-O-alpha-L-arabinopyranosyl)-beta-D-glucopyranoside (83 microg/g fr. wt of cells), were isolated from the cell suspension after three days of incubation with capsaicin. Two other compounds, 8-nordihydrocapsaicin 4-O-(6-O-beta-D-xylopyranosyl)-beta-D-glucopyranoside (171 microg/g fr. wt of cells) and 8-nordihydrocapsaicin 4-O-(6-O-alpha-L-arabinopyranosyl)-beta-D-glucopyranoside (122 microg/g fr. wt of cells), together with the known 8-nordihydrocapsaicin 4-O-beta-D-glucopyranoside (204 microg/g fr. wt of cells) were also isolated from the cell suspension after incubation with 8-nordihydrocapsaicin. 相似文献
974.
Takeuchi Y Nomura W Ohdate T Tamasu S Masutani H Murata K Izawa S Yodoi J Inoue Y 《Applied microbiology and biotechnology》2007,75(6):1393-1399
Thioredoxin is crucial for the maintenance of the redox status of cells of all types. Mammalian thioredoxin is secreted from
various types of cells, although the mechanism underlying has not yet been clarified. Previously, we demonstrated that thioredoxin
was released from Saccharomyces cerevisiae after treatment with ethanol. In this paper, we show that as well as ethanol, low-pH shock and hypoosmotic shock release
thioredoxin. Low-molecular-weight proteins in yeast cells were preferentially released by treatment with ethanol and low-pH
shock. A cell wall integrity pathway seems partially involved in the hypoosmotic shock-induced release of thioredoxin. Considerable
amounts of thioredoxin were present in the insoluble fractions of the cells, a portion of which was associated with lipid
microdomains that are resistant to nonionic detergent at 4°C. The intracellular localization of thioredoxin may influence
the efficiency of its release from yeast cells with ethanol. 相似文献
975.
Nishimura Y Maeda S Ikushiro S Mackenzie PI Ishii Y Yamada H 《Biochimica et biophysica acta》2007,1770(11):1557-1566
The inhibitory effects of nucleotides and related substances on rat hepatic UDP-glucuronosyltransferase (UGT) were studied. ATP and NADP+ markedly reduced 4-methylumbelliferone (4-MU) UGT activity only when detergent-treated rat liver microsomes were used as the enzyme source. The IC50 values of adenine, ATP, NAD+ and NADP+ were estimated to be below 20 microM, whereas AMP had no inhibitory effect. From the kinetic behavior observed, these adenine-related compounds were assumed to inhibit UGT activity non-competitively without competing with either 4-MU or UDP-glucuronic acid. Among guanine, cytosine and their related nucleotides, only triphosphate nucleotides (CTP and GTP) exhibited potent UGT inhibition, although the effect of GTP was weak. Estradiol 3- and 17-glucuronidation were also inhibited by the inhibitors of 4-MU UGT. The only exception was that estradiol 17-glucuronidation activity was inhibited by AMP (IC50=31 microM). In addition, AMP antagonized the inhibitory effects of adenine, ATP, and NADP+ on 4-MU and estradiol 3- glucuronidation activities. These results suggest that (1) a number of cellular nucleotides present within the endoplasmic reticulum regulate UGT function; and (2) these substances bind to a common allosteric site on UGT to reduce catalytic function. 相似文献
976.
Kasai S Urushibata S Hozumi K Yokoyama F Ichikawa N Kadoya Y Nishi N Watanabe N Yamada Y Nomizu M 《Biochemistry》2007,46(13):3966-3974
Amyloid fibril formation is associated with several pathologies, including Alzheimer's disease, Parkinson's disease, type II diabetes, and prion diseases. Recently, a relationship between basement membrane components and amyloid deposits has been reported. The basement membrane protein, laminin, may be involved in amyloid-related diseases, since laminin is present in amyloid plaques in Alzheimer's disease and binds to amyloid precursor protein. Recently, we showed that peptide A208 (AASIKVAVSADR), the IKVAV-containing peptide, formed amyloid-like fibrils. We previously identified 60 cell adhesive sequences in laminin-1 using a total of 673 12-mer synthetic peptides. Here, we screened for additional amyloidogenic sequences among 60 cell adhesive peptides derived from laminin-1. We first examined amyloid-like fibril formation by the 60 active peptides with Congo red, a histological dye binding to many amyloid-like proteins. Thirteen peptides were stained with Congo red. Four of the 13 peptides promoted cell attachment and neurite outgrowth like the IKVAV-containing peptide. The four peptides also showed amyloid-like fibril formation in both X-ray diffraction and electron microscopic analyses. The amyloidogenic peptides contain consensus amino acid components, including both basic and acidic amino acids and Ser and Ile residues. These results indicate that at least five laminin-derived peptides can form amyloid-like fibrils. We conclude that the laminin-derived amyloidogenic peptides have the potential to form amyloid-like fibrils in vivo, possibly when laminin-1 is degraded. 相似文献
977.
Ai S Cheng XW Inoue A Nakamura K Okumura K Iguchi A Murohara T Kuzuya M 《Biochemical and biophysical research communications》2007,364(2):395-401
Neutrophil elastase (NE), a serine protease released from the azurophil granules of activated neutrophil, proteolytically cleaves multiple cytokines, and cell surface proteins. In the present study, we examined whether NE affects the biological abilities of angiogenic growth factors such as basic-fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). NE degraded bFGF and VEGF in a time- and concentration-dependent manner, and these degradations were suppressed by sivelestat, a synthetic inhibitor of NE. The bFGF- or VEGF-mediated proliferative activity of human umbilical vein endothelial cells was inhibited by NE, and the activity was recovered by sivelestat. Furthermore, NE reduced the bFGF- or VEGF-induced tubulogenic response of the mice aortas, ex vivo angiogenesis assay, and these effects were also recovered by sivelestat. Neutrophil-derived NE degraded potent angiogenic factors, resulting in loss of their angiogenic activity. These findings provide additional insight into the role played by neutrophils in the angiogenesis process at sites of inflammation. 相似文献
978.
Three slit genes, slit1 to slit3, have been cloned to date. Slit1 and slit2 act as chemorepellent factors for axon guidance. Slit3 is involved in the formation of the diaphragm and kidney during embryogenesis. However, its molecular function remains unclear. We found that slit3 expression was induced by lipopolysaccharide (LPS)-stimulation in macrophages and that it was localized in the mitochondria and along the plasma membrane. Silencing of slit3 expression by RNA interference reduced cell motility and Rac/Cdc42 activation. These results suggest that slit3 functions as an intracellular signaling molecule for cell motility as part of the LPS-induced signaling cascade. 相似文献
979.
A<Emphasis Type="Bold">β</Emphasis> Upregulates and Colocalizes with LGI3 in Cultured Rat Astrocytes
Kimura N Ishii Y Suzaki S Negishi T Kyuwa S Yoshikawa Y 《Cellular and molecular neurobiology》2007,27(3):335-350
1. The leucine-rich glioma inactivated (LGI) family of genes encodes a leucine-rich repeat (LRR) protein, proteins that are
thought to be specifically involved in protein–protein and protein–matrix interactions. Since amyloid beta peptide (Aβ) has
been previously shown to induce the expression of another LRR-encoding gene in neural cells, we assessed how Aβ affects LGI
gene expression in rat primary cerebral cortical cultures and astrocyte cultures. Both RT-PCR and Western Blotting analyses
revealed that Aβ robustly induced the expression of LGI3 in rat astrocyte cultures.
2. Western Blotting analyses also showed that both glial fibrillary acidic protein (GFAP) and apolipoprotein E (ApoE) significantly
increased coincidentally with the Aβ-induced upregulation of LGI3. Immunocytochemistry showed that LGI3 colocalized with Aβ
at plasma membranes and also with internalized Aβ in astrocytes. These findings suggest that activated LGI3 may be involved
in the astroglial response against Aβ. 相似文献
980.