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951.
Ken-ichi Tamura Jun-ichi Yonemaru Hiroshi Hisano Hiroyuki Kanamori Julie King Ian P. King Kazuhiro Tase Yasuharu Sanada Toshinori Komatsu Toshihiko Yamada 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(8):1549-1560
DNA markers able to distinguish species or genera with high specificity are valuable in the identification of introgressed
regions in interspecific or intergeneric hybrids. Intergeneric hybridization between the genera of Lolium and Festuca, leading to the reciprocal introgression of chromosomal segments, can produce novel forage grasses with unique combinations
of characteristics. To characterize Lolium/Festuca introgressions, novel PCR-based expression sequence tag (EST) markers were developed. These markers were designed around
intronic regions which show higher polymorphism than exonic regions. Intronic regions of the grass genes were predicted from
the sequenced rice genome. Two hundred and nine primer sets were designed from Lolium/Festuca ESTs that showed high similarity to unique rice genes dispersed uniformly throughout the rice genome. We selected 61 of these
primer sets as insertion-deletion (indel)-type markers and 82 primer sets as cleaved amplified polymorphic sequence (CAPS)
markers to distinguish between Lolium perenne and Festuca pratensis. Specificity of these markers to each species was evaluated by the genotyping of four cultivars and accessions (32 individuals)
of L. perenne and F. pratensis, respectively. Evaluation using specificity indices proposed in this study suggested that many indel-type markers had high
species specificity to L. perenne and F. pratensis, including 15 markers completely specific to both species. Forty-nine of the CAPS markers completely distinguish between
the two species at bulk level. Chromosome mapping of these markers using a Lolium/Festuca substitution line revealed syntenic relationships between Lolium/Festuca and rice largely consistent with previous reports. This intron-based marker system that shows a high level of polymorphisms
between species in combination with high species specificity will consequently be a valuable tool in Festulolium breeding.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
952.
Tamaki Wada Makoto Honda Itsunari Minami Norie Tooi Yuji Amagai Norio Nakatsuji Kazuhiro Aiba 《PloS one》2009,4(8)
Background
There are no cures or efficacious treatments for severe motor neuron diseases. It is extremely difficult to obtain naïve spinal motor neurons (sMNs) from human tissues for research due to both technical and ethical reasons. Human embryonic stem cells (hESCs) are alternative sources. Several methods for MN differentiation have been reported. However, efficient production of naïve sMNs and culture cost were not taken into consideration in most of the methods.Methods/Principal Findings
We aimed to establish protocols for efficient production and enrichment of sMNs derived from pluripotent stem cells. Nestin+ neural stem cell (NSC) clusters were induced by Noggin or a small molecule inhibitor of BMP signaling. After dissociation of NSC clusters, neurospheres were formed in a floating culture containing FGF2. The number of NSCs in neurospheres could be expanded more than 30-fold via several passages. More than 33% of HB9+ sMN progenitor cells were observed after differentiation of dissociated neurospheres by all-trans retinoic acid (ATRA) and a Shh agonist for another week on monolayer culture. HB9+ sMN progenitor cells were enriched by gradient centrifugation up to 80% purity. These HB9+ cells differentiated into electrophysiologically functional cells and formed synapses with myotubes during a few weeks after ATRA/SAG treatment.Conclusions and Significance
The series of procedures we established here, namely neural induction, NSC expansion, sMN differentiation and sMN purification, can provide large quantities of naïve sMNs derived from human and monkey pluripotent stem cells. Using small molecule reagents, reduction of culture cost could be achieved. 相似文献953.
Takahiro Fujimoto Kyoko Miyasaka Midori Koyanagi Toshiyuki Tsunoda Iwai Baba Keiko Doi Minoru Ohta Norihiro Kato Takehiko Sasazuki Senji Shirasawa 《PloS one》2009,4(1)
Obesity and related metabolic disorders have become leading causes of adult morbidity and mortality. KRAP (Ki-ras-induced actin-interacting protein) is a cytoskeleton-associated protein and a ubiquitous protein among tissues, originally identified as a cancer-related molecule, however, its physiological roles remain unknown. Here we demonstrate that KRAP-deficient (KRAP−/−) mice show enhanced metabolic rate, decreased adiposity, improved glucose tolerance, hypoinsulinemia and hypoleptinemia. KRAP−/− mice are also protected against high-fat diet-induced obesity and insulin resistance despite of hyperphagia. Notably, glucose uptake in the brown adipose tissue (BAT) in KRAP−/− mice is enhanced in an insulin-independent manner, suggesting that BAT is involved in altered energy homeostasis in KRAP−/− mice, although UCP (Uncoupling protein) expressions are not altered. Of interest is the down-regulation of fatty acid metabolism-related molecules, including acetyl-CoA carboxylase (ACC)-1, ACC-2 and fatty acid synthase in the liver of KRAP
−/− mice, which could in part account for the metabolic phenotype in KRAP−/− mice. Thus, KRAP is a novel regulator in whole-body energy homeostasis and may be a therapeutic target in obesity and related diseases. 相似文献
954.
955.
The ubiquitin‐conjugation system regulates a vast range of biological phenomena by affecting protein function mostly through polyubiquitin conjugation. The type of polyubiquitin chain that is generated seems to determine how conjugated proteins are regulated, as they are recognized specifically by proteins that contain chain‐specific ubiquitin‐binding motifs. An enzyme complex that catalyses the formation of newly described linear polyubiquitin chains—known as linear ubiquitin chain‐assembly complex (LUBAC)—has recently been characterized, as has a particular ubiquitin‐binding domain that specifically recognizes linear chains. Both have been shown to have crucial roles in the canonical nuclear factor‐κB (NF‐κB)‐activation pathway. The ubiquitin system is intimately involved in regulating the NF‐κB pathway, and the regulatory roles of K63‐linked chains have been studied extensively. However, the role of linear chains in this process is only now emerging. This article discusses the possible mechanisms underlying linear polyubiquitin‐mediated activation of NF‐κB, and the different roles that K63‐linked and linear chains have in NF‐κB activation. Future directions for linear polyubiquitin research are also discussed. 相似文献
956.
Yurika Yogo Seitaro Fujishima Takashi Inoue Fumitake Saito Takayuki Shiomi Kazuhiro Yamaguchi Akitoshi Ishizaka 《Respiratory research》2009,10(1):80
Background
Idiopathic pulmonary fibrosis (IPF) is a chronically progressive interstitial lung disease of unknown etiology. Previously, we have demonstrated the selective upregulation of the macrophage-derived chemokine CCL22 and the thymus activation-regulated chemokine CCL17 among chemokines, in a rat model of radiation pneumonitis/pulmonary fibrosis and preliminarily observed an increase in bronchoalveolar (BAL) fluid CCL22 levels of IPF patients.Methods
We examined the expression of CCR4, a specific receptor for CCL22 and CCL17, in bronchoalveolar lavage (BAL) fluid cells, as well as the levels of CCL22 and CCL17, to elucidate their pathophysiological roles in pulmonary fibrosis. We also studied their immunohistochemical localization.Results
BAL fluid CCL22 and CCL17 levels were significantly higher in patients with IPF than those with collagen vascular diseases and healthy volunteers, and there was a significant correlation between the levels of CCL22 and CCL17 in patients with IPF. CCL22 levels in the BAL fluid did not correlate with the total cell numbers, alveolar lymphocytes, or macrophages in BAL fluid. However, the CCL22 levels significantly correlated with the numbers of CCR4-expressing alveolar macrophages. By immunohistochemical and immunofluorescence analysis, localization of CCL22 and CCR4 to CD68-positive alveolar macrophages as well as that of CCL17 to hyperplastic epithelial cells were shown. Clinically, CCL22 BAL fluid levels inversely correlated with DLco/VA values in IPF patients.Conclusion
We speculated that locally overexpressed CCL22 may induce lung dysfunction through recruitment and activation of CCR4-positive alveolar macrophages. 相似文献957.
Microdissection of Shoot Meristem Functional Domains 总被引:1,自引:0,他引:1
958.
Biodegradation of diphenylarsinic acid to arsenic acid by novel soil bacteria isolated from contaminated soil 总被引:2,自引:0,他引:2
Naoki Harada Kazuhiro Takagi Koji Baba Kunihiko Fujii Akio Iwasaki 《Biodegradation》2010,21(3):491-499
Microorganisms capable of degrading diphenylarsinic acid (DPAA) were enriched from contaminated soil using the soil-charcoal
perfusion method. Two novel bacterial strains, L2406 and L2413, that can degrade DPAA in a mineral salt medium supplemented
with DPAA as the sole carbon source were isolated. Based on comparative morphology, physiology, and comparison of the 16S
rRNA gene sequences, both were presumed to be species closely related to Ensifer adhaerens. As the metabolites, phenylarsonic acid (PAA) was determined by liquid chromatography-mass spectrometry analysis as well
as three unknown peaks all of whose molecular weights were estimated to be 278. The increase of m/z = 16 from DPAA in the
unknowns suggests monohydroxylation of DPAA at the 2-, 3- and 4-positions. The ability of strains L2406 and L2413 to degrade
DPAA was suppressed in iron insufficient conditions, e.g. less than 7.2 μM iron in the culture medium. These facts strongly
suggest the following hypothesis: Monooxygenase works at the initial degradation step of DPAA degradation by the isolates;
and direct hydrolysis from DPAA to PAA is not likely to occur. In addition, release of arsenic acid from PAA by strain L2406
was confirmed by liquid chromatography-inductively coupled plasma mass spectrometry. From these results, strain L2406 was
considered to be capable of degrading DPAA to arsenic acid via PAA when DPAA was supplied as the sole carbon source. 相似文献
959.
960.
Toru Fukuda Shoichiro Kokabu Satoshi Ohte Hiroki Sasanuma Kazuhiro Kanomata Katsumi Yoneyama Hitoshi Kato Masumi Akita Hiromi Oda Takenobu Katagiri 《Differentiation; research in biological diversity》2010
Both BMPs and Wnts play important roles in the regulation of bone formation. We examined the molecular mechanism regulating cross-talk between BMPs and Wnts in the osteoblastic differentiation of C2C12 cells. Canonical Wnts (Wnt1 and Wnt3a) but not non-canonical Wnts (Wnt5a and Wnt11) synergistically stimulated ALP activity in the presence of BMP-4. Wnt3a and BMP-4 synergistically stimulated the expression of type I collagen and osteonectin. However, Wnt3a did not stimulate ALP activity that was induced by a constitutively active BMP receptor or Smad1. Noggin and Dkk-1 suppressed the synergistic effect of BMP-4 and Wnt3a, but Smad7 did not. Overexpression of β-catenin did not affect BMP-4-induced ALP activity. By contrast, inhibition or stimulation of GSK3β activity resulted in either stimulation or suppression of ALP activity, respectively, in the presence of BMP-4. Taken together, these findings suggest that BMPs and canonical Wnts may regulate osteoblastic differentiation, especially at the early stages, through a GSK3β-dependent but β-catenin-independent mechanism. 相似文献