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121.
Neoplastic plant-tissue formation, termed crown gall disease, is induced on infection with Agrobacterium tumefaciens. The tumorous tissues develop an extensive vascular system, with a venation pattern distinct from that of native host plants.
We report here that the plant-tumorigenic 6b gene of the A. tumefaciens strain AKE10 is capable of inducing extensive vein formation in transgenic tobacco seedlings with distinct pattern formation.
Unlike the wild-type cotyledons, transgenic cotyledons had wavy and striate veins depending on the extent of severity of leaf
morphology. Graph analysis of the transgenic cotyledonous vein patterns revealed an increase in the number of branch points
of veins, end-points of veins, and areas surrounded by the veins. Histological analysis showed abnormal tissue growth on the
abaxial side of the cotyledon blades and continual formation of adventitious veins. These adventitiously formed veins included
inverted dorso-ventrality and formation of a radial axis. 相似文献
122.
123.
Aya Nagaoka Hiroyuki Yoshida Sachiko Nakamura Tomohiko Morikawa Keigo Kawabata Masaki Kobayashi Shingo Sakai Yoshito Takahashi Yasunori Okada Shintaro Inoue 《The Journal of biological chemistry》2015,290(52):30910-30923
Regulation of hyaluronan (HA) synthesis and degradation is essential to maintenance of extracellular matrix homeostasis. We recently reported that HYBID (HYaluronan-Binding protein Involved in hyaluronan Depolymerization), also called KIAA1199, plays a key role in HA depolymerization in skin and arthritic synovial fibroblasts. However, regulation of HA metabolism mediated by HYBID and HA synthases (HASs) under stimulation with growth factors remains obscure. Here we report that TGF-β1, basic FGF, EGF, and PDGF-BB commonly enhance total amount of HA in skin fibroblasts through up-regulation of HAS expression, but molecular size of newly produced HA is dependent on HYBID expression levels. Stimulation of HAS1/2 expression and suppression of HYBID expression by TGF-β1 were abrogated by blockade of the MAPK and/or Smad signaling and the PI3K-Akt signaling, respectively. In normal human skin, expression of the TGF-β1 receptors correlated positively with HAS2 expression and inversely with HYBID expression. On the other hand, TGF-β1 up-regulated HAS1/2 expression but exerted only a slight suppressive effect on HYBID expression in synovial fibroblasts from the patients with osteoarthritis or rheumatoid arthritis, resulting in the production of lower molecular weight HA compared with normal skin and synovial fibroblasts. These data demonstrate that although TGF-β1, basic FGF, EGF, and PDGF-BB enhance HA production in skin fibroblasts, TGF-β1 most efficiently contributes to production of high molecular weight HA by HAS up-regulation and HYBID down-regulation and suggests that inefficient down-regulation of HYBID by TGF-β1 in arthritic synovial fibroblasts may be linked to accumulation of depolymerized HA in synovial fluids in arthritis patients. 相似文献
124.
Ecological niche breadth and microhabitat guild structure in temperate Australian reptiles: Implications for natural resource management in endangered grassy woodland ecosystems 下载免费PDF全文
Damian R. Michael Geoffrey M. Kay Mason Crane Daniel Florance Christopher MacGregor Sachiko Okada Lachlan McBurney David Blair David B. Lindenmayer 《Austral ecology》2015,40(6):651-660
Ecological theory predicts that species with narrow niche requirements (habitat specialists) are more vulnerable to anthropocentric disturbances than those with broad niche requirements (habitat generalists). Hence, understanding a species ecological niche and guild membership would serve as a valuable management tool for providing a priori assessments of a species extinction risk. It also would help to forecast a species capacity to respond to land use change, as what might be expected to occur under financial incentive schemes to improve threatened ecological vegetation communities. However, basic natural history information is lacking for many terrestrial species, particularly reptiles in temperate regions of the world. To overcome this limitation, we collated 3527 reptile observations from 52 species across an endangered woodland ecoregion in south‐eastern Australia and examined ecological niche breadth and microhabitat guild structure. We found 30% of species had low ecological niche values and were classified as habitat specialists associated with large eucalypt trees, woody debris, surface rock or rocky outcrops. Cluster analysis separated species into six broad guilds based on microhabitat similarity. Approximately 80% of species belonged to guilds associated with old growth vegetation attributes or non‐renewable litho‐resources such as surface rock or rocky outcrops. Our results suggest that agri‐environment schemes that focus purely on grazing management are unlikely to provide immediate benefits to broad suites of reptiles associated with old growth vegetation and litho‐resources. Our classification scheme will be useful for identifying reptile species that are potentially vulnerable to anthropocentric disturbances and may require alternative strategies for improving habitat suitability and reptile conservation outcomes in grassy woodland ecosystems. 相似文献
125.
Shiba S Tsunoda N Wakutsu M Muraki E Sonoda M Tam PS Fujiwara Y Ikemoto S Kasono K 《Bioscience, biotechnology, and biochemistry》2011,75(12):2401-2403
We investigated whether oral administration of palmitoleate ameliorates disorders of lipid metabolism to clarify the effects of one of the components of fish oil. Lipid levels in the liver and plasma were significantly decreased by palmitoleate and by EPA administration. These results suggest that palmitoleate, in addition to EPA, plays a role in the regulation of lipid metabolism by fish oil. 相似文献
126.
Keiichi Okada Sachiko Okada Koh Yasue Masaki Fukuda Akiyoshi Yamada 《Ecological Research》2011,26(2):411-419
Ectomycorrhizas (EM) are among the most active components of forest soil biomass because they represent the dominant soil
carbon efflux from forests. However, temporal patterns of EM biomass in relation to climatic factors and host tree growth
remain unclear. We sampled EM and fine roots of pine each month for 6 years (May 2003 to June 2009) in a 40–50-year-old Pinus densiflora forest in Japan. Tree ring width of host pines in the plot was measured to assess the chronological sequence of annual tree
growth. EM biomass was not stable during the 6 years of monitoring and seasonal patterns were indistinct. Multiple correlation
analyses revealed that the autumn precipitation in the previous year was the most determinative factor of EM biomass in the
current year, with a negative correlation. In contrast, tree ring width generally showed a stable annual growth pattern throughout
the monitoring period. Clarification of such a carbon allocation pattern is important in understanding forest carbon dynamics
under a temperate monsoon climate. 相似文献
127.
Otani T Oshima K Onishi S Takeda M Shinmyozu K Yonemura S Hayashi S 《Developmental cell》2011,20(2):219-232
Highlights? Recycling endosomes shuttle along the proximal-distal axis of growing bristles ? IKK? locally antagonizes Rab11 effector Nuf at the bristle tip by phosphorylation ? Nuf-endosome pathway is independent of actin cytoskeleton or DIAP1-caspase pathway ? Mammalian IKK-related kinases antagonize Rab11-FIP3 through phosphorylation 相似文献
128.
Feng Li Yoichi Hasegawa Masako Saito Sachiko Shirasawa Aki Fukushima Toyoaki Ito Hiroshi Fujii Sachie Kishitani Hiroyasu Kitashiba Takeshi Nishio 《DNA research》2011,18(5):401-411
A linkage map of expressed sequence tag (EST)-based markers in radish (Raphanus sativus L.) was constructed using a low-cost and high-efficiency single-nucleotide polymorphism (SNP) genotyping method named multiplex polymerase chain reaction–mixed probe dot-blot analysis developed in this study. Seven hundred and forty-six SNP markers derived from EST sequences of R. sativus were assigned to nine linkage groups with a total length of 806.7 cM. By BLASTN, 726 markers were found to have homologous genes in Arabidopsis thaliana, and 72 syntenic regions, which have great potential for utilizing genomic information of the model species A. thaliana in basic and applied genetics of R. sativus, were identified. By construction and analysis of the genome structures of R. sativus based on the 24 genomic blocks within the Brassicaceae ancestral karyotype, 23 of the 24 genomic blocks were detected in the genome of R. sativus, and half of them were found to be triplicated. Comparison of the genome structure of R. sativus with those of the A, B, and C genomes of Brassica species and that of Sinapis alba L. revealed extensive chromosome homoeology among Brassiceae species, which would facilitate transfer of the genomic information from one Brassiceae species to another. 相似文献
129.
Tight-junction strands, which are organized into the beltlike cell-cell adhesive structure called the zonula occludens (TJ), create the paracellular permselective barrier in epithelial cells. The TJ is constructed on the basis of the zonula adherens (AJ) by polymerized claudins in a process mediated by ZO-1/2, but whether the 24 individual claudin family members play different roles at the TJ is unclear. Here we established a cell system for examining the polymerization of individual claudins in the presence of ZO-1/2 using an epithelial-like cell line, SF7, which lacked endogenous TJs and expressed no claudin but claudin-12 in immunofluorescence and real-time PCR assays. In stable SF7-derived lines, exogenous claudin-7, -14, or -19, but no other claudins, individually reconstituted TJs, each with a distinct TJ-strand pattern, as revealed by freeze-fracture analyses. Fluorescence recovery after photobleaching (FRAP) analyses of the claudin dynamics in these and other epithelial cells suggested that slow FRAP-recovery dynamics of claudins play a critical role in regulating their polymerization around AJs, which are loosely coupled with ZO-1/2, to form TJs. Furthermore, the distinct claudin stabilities in different cell types may help to understand how TJs regulate paracellular permeability by altering the paracellular flux and the paracellular ion permeability. 相似文献
130.
Scarisbrick IA Epstein B Cloud BA Yoon H Wu J Renner DN Blaber SI Blaber M Vandell AG Bryson AL 《PloS one》2011,6(3):e18376