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81.
Kota Asano Mitsumi Arito Manae S. Kurokawa Kazuki Omoteyama Kazuki Okamoto Naoya Suematsu Kazuo Yudoh Hiroshi Nakamura Moroe Beppu Tomohiro Kato 《Biochemical and biophysical research communications》2014
Layilin (LAYN) is thought to be involved in reorganization of cytoskeleton structures, interacting with merlin, radixin, and talin. Also, LAYN is known to be one of the receptors for hyaluronic acid (HA). 相似文献
82.
Miyako Kusano Atsushi Fukushima Henning Redestig Makoto Kobayashi Hitomi Otsuki Hitoshi Onouchi Satoshi Naito Masami Yokota Hirai Kazuki Saito 《Amino acids》2010,39(4):1013-1021
Methionine (Met) is an essential amino acid for all organisms. In plants, Met also functions as a precursor of plant hormones,
polyamines, and defense metabolites. The regulatory mechanism of Met biosynthesis is highly complex and, despite its great
importance, remains unclear. To investigate how accumulation of Met influences metabolism as a whole in Arabidopsis, three methionine over-accumulation (mto) mutants were examined using a gas chromatography–mass spectrometry-based metabolomics approach. Multivariate statistical
analyses of the three mto mutants (mto1, mto2, and mto3) revealed distinct metabolomic phenotypes. Orthogonal projection to latent structures–discriminant analysis highlighted discriminative
metabolites contributing to the separation of each mutant and the corresponding control samples. Though Met accumulation in
mto1 had no dramatic effect on other metabolic pathways except for the aspartate family, metabolite profiles of mto2 and mto3 indicated that several extensive pathways were affected in addition to over-accumulation of Met. The pronounced changes
in metabolic pathways in both mto2 and mto3 were associated with polyamines. The findings suggest that our metabolomics approach not only can reveal the impact of Met
over-accumulation on metabolism, but also may provide clues to identify crucial pathways for regulation of metabolism in plants. 相似文献
83.
Kazuki Oka Naotoshi Yoshiyama Koji Tojo Ryuichiro Machida Masatsugu Hatakeyama 《Development genes and evolution》2010,220(1-2):53-59
Larvae of the sawfly, Athalia rosae, have remarkable abdominal prolegs. We analyzed the morphogenesis of appendages and the expression of decapentaplegic and Distal-less genes during embryonic development to characterize the origin of prolegs. Proleg primordia in abdominal segments A1–A9 appeared shortly after the inner lobes (endites) of gnathal appendages were formed. These were located on the ventral plates, medioventral to the appendages of the other segments in light of serial homology. Nothing was seen where the main axis of the appendage should develop in abdominal segments. The primordia in A1 and A9 disappeared before larval hatching. Anal prolegs appeared separate from cerci, the main axes of appendages, which were formed temporarily in A11. The expression of decapentaplegic, which reflects the primary determination of appendages, was detected in the lateral juxtaposition with the prolegs. Distal-less was expressed in the main axes of appendages, protruding endites and the cerci, but not in prolegs and anal prolegs or the gnathal endites which do not protrude. These findings suggest a possibility that the abdominal and anal prolegs of A. rosae are outgrowths of ventral plates which derived from coxopodal elements, but not main axes of appendages. 相似文献
84.
85.
Nakazawa Y Sagane Y Kikuchi T Uchino M Nagai T Sato H Toeda K Takano K 《The protein journal》2010,29(8):598-608
We previously isolated Streptomyces racemochromogenes strain 10-3, which produces a phospholipase D (PLD) with high transphosphatidylation activity. Here, we purified and cloned
the PLD (PLD103) from the strain. PLD103 exerted the highest hydrolytic activity at a slightly alkaline pH, which is in contrast
to the majority of known Streptomyces PLDs that have a slightly acidic optimum pH. PLD103 shares only 71–76% amino acid sequence identity with other Streptomyces PLDs that have a slightly acidic optimum pH; thus, the diversity in the primary structure might explain the discrepancy observed
in the optimum pH. The purified PLD displayed high transphosphatidylation activity in the presence of glycerol, l-serine, and 2-aminoethanol hydrochloride with a conversion rate of 82–97% in a simple one-phase system, which was comparable
to the rate of other Streptomyces PLDs in a complicated biphasic system. 相似文献
86.
87.
Eri Suzuki Hiroto Okuda Kentaro Nishida Sadaki Fujimoto Kazuki Nagasawa 《Life sciences》2010,86(17-18):676-682
AimPoly(ADP-ribose) polymerase-1 (PARP-1) is a DNA repair enzyme, and its excessive activation, following ischemia, trauma, etc., depletes cellular nicotinamide adenine dinucleotide (NAD+) as a substrate and eventually leads to brain cell death. Nicotinamide, an NAD+ precursor and a PARP-1 inhibitor, is known to prevent PARP-1-triggered cell death, but there is no available information on the mechanisms involved in its transport. Here we clarified the transport characteristics of nicotinamide in primary cultured mouse astrocytes.Main methodsUptake characteristics of [14C]nicotinamide were assessed by a conventional method with primary cultured mouse astrocytes. Cell viability and PARP-1 activity were determined with intracellular LDH activity and immunocytochemical detection of PAR accumulation, respectively.Key findingsPARP-1 activation was induced by treatment of astrocytes with N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), an alkylating agent. MNNG-triggered astrocyte death and PAR accumulation were completely inhibited by treatment with nicotinamide as with DPQ (3,4-dihydro-5-(4-(1-piperidinyl)butoxy)-1(2H)-isoquinolinone), a second generation PARP inhibitor. The uptake of [14C]nicotinamide was time-, temperature-, concentration- and pH-dependent, and was inhibited and stimulated by co- and pre-treatment with N-methylnicotinamide, a representative substrate of an organic cation transport system, respectively. Co-treatment of astrocytes with nicotinamide and N-methylnicotinamide resulted in a decrease in PAR accumulation and absolute prevention of cell death.SignificanceThese findings suggest that nicotinamide has a protective effect against PARP-1-induced astrocyte death and that its transporter-mediated uptake, which is extracellular pH-sensitive and common to N-methylnicotinamide, is critical for prevention of PARP-1-triggered cell death. 相似文献
88.
We have developed a new NIR fluorescent probe based on an ytterbium(III) (E)‐1‐(pyridin‐2‐yl‐diazenyl)naphthalen‐2‐ol (PAN) complex. This probe emits near‐infrared luminescence derived from the Yb ion through excitation of the PAN moiety with visible light (λex = 530 nm, λem = 975 nm). The results support the possible utility of the probe for in vivo fluorescence molecular imaging. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
89.
Mesenchymal stem cells (MSCs) are defined as cells that undergo sustained in vitro growth and are able to give rise to multiple mesenchymal lineages. Although MSCs are already used in regenerative medicine little is known about their in vivo behavior and developmental derivation. Here, we show that the earliest wave of MSC in the embryonic trunk is generated from Sox1+ neuroepithelium but not from mesoderm. Using lineage marking by direct gfp knock-in and Cre-recombinase mediated lineage tracing, we provide evidence that Sox1+ neuroepithelium gives rise to MSCs in part through a neural crest intermediate stage. This pathway can be distinguished from the pathway through which Sox1+ cells give rise to oligodendrocytes by expression of PDGFRbeta and A2B5. MSC recruitment from this pathway, however, is transient and is replaced by MSCs from unknown sources. We conclude that MSC can be defined as a definite in vivo entity recruited from multiple developmental origins. 相似文献
90.