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101.
Oxidative DNA damage caused by a cysteine metal-catalyzed oxidation system (Cys-MCO) comprised of Fe(3+), O(2), and a cysteine as an electron donor was enhanced by copper, zinc superoxide dismutase (CuZnSOD) in a concentration-dependent manner, as reflected by the formation of 8-hydroxy-2'-deoxyguanosine (8-OH-dG) and strand breaks. Unlike CuZnSOD, manganese SOD (MnSOD) as well as iron SOD (FeSOD) did not enhance DNA damage. The capacity of CuZnSOD to enhance damage to DNA was inhibited by a spin-trapping agent, 5, 5-dimethyl-1-pyrroline N-oxide (DMPO) and a metal chelator, diethylenetriaminepentaacetic acid (DETAPAC). The deoxyribose assay showed that hydroxyl free radicals were generated in the reaction of CuZnSOD with Cys-MCO. We found that the Cys-MCO system caused the release of free copper from CuZnSOD. CuZnSOD also caused the two-fold enhancement of a mutation in the pUC18 lacZ' gene in the presence of Cys-MCO when measured as a loss of alpha-complementation. Based on these results, we interpret the effects of CuZnSOD on Cys-MCO-induced DNA damage and mutation as due to reactive oxygen species, probably hydroxyl free radicals, formed by the reaction of free Cu(2+), released from oxidatively damaged CuZnSOD, and H(2)O(2) produced by the Cys-MCO system. 相似文献
102.
Direct gene delivery into isolated microspores of rapeseed (Brassica napus L.) and the production of fertile transgenic plants 总被引:6,自引:0,他引:6
A procedure for direct gene transfer into isolated microspores of rapeseed (Brassica napus L.) and the production of fertile transgenic plants is presented. By modifying the microspore culture method and adopting
the firefly luciferase (Luc) gene as a non-destructive marker, we could obtain stably transformed androgenetic embryos from
bombarded microspores. Luc-positive embryos were easily isolated from the large non-transformed population using a high-sensitivity
bioluminescent image analyzer. PCR and Southern blot analyses confirmed that the introduced transgene was integrated stably
into the genome of the selected embryos. Diploidized plants obtained from the haploid embryos were self-pollinated, and all
of the offspring tested were Luc-positive, indicating rapid fixation of the transgene which is characteristic of doubled haploids.
Received: 14 May 1997 / Revision received: 15 July 1997 / Accepted: 28 July 1997 相似文献
103.
Over-expression of a tobacco homeobox gene,
NTH15
, decreases the expression of a gibberellin biosynthetic gene encoding GA 20-oxidase 总被引:9,自引:3,他引:6
Miyako Tanaka-Ueguchi Hironori Itoh Naomi Oyama Masaji Koshioka Makoto Matsuoka 《The Plant journal : for cell and molecular biology》1998,15(3):391-400
Ectopic expression of the homeobox gene, NTH15 ( Nicotiana tabacum homeobox 15) in transgenic tobacco leads to abnormal leaf and flower morphology, accompanied by a decrease in the content of the active gibberellin, GA1. Quantitative analysis of intermediates in the GA biosynthetic pathway revealed that the step from GA19 to GA20 was blocked in transgenic tobacco plants overexpressing NTH15 . To investigate the relationship between the expression of NTH15 and genes involved in GA biosynthesis, we isolated three cDNA clones from tobacco encoding two types of GA 20-oxidase and a 3β-hydroxylase. RNA gel blot analysis revealed that the expression of one gene ( Ntc12 , encoding GA 20-oxidase), which in wild-type tobacco plants was abundantly expressed in leaves, was strongly suppressed in the transformants. The expression level of Ntc12 decreased with increasing severity of phenotype of transgenic tobacco leaves. The abnormal leaf morphology was largely overcome by treatment with GA20 or GA1 but not by GA19. These data strongly suggest that overexpression of NTH15 inhibits the expression of Ntc12 , resulting in reduced levels of active GA and abnormal leaf morphology in transgenic tobacco plants. In situ hybridization in wild-type tobacco revealed that expression of Ntc12 occurred mainly in the rib meristem, cells surrounding the procambium and in leaf primordia. Expression was not seen in the tunica, corpus and procambium, tissues in which NTH15 was predominantly expressed. The contrasting expression patterns of these genes may reflect their antagonistic functions in the formation of lateral organs from the shoot apical meristem. 相似文献
104.
Oana S Machida S Hiratsuka E Furutani Y Momma K Takao A Matsuoka R 《Biology of the cell / under the auspices of the European Cell Biology Organization》1998,90(9):605-613
We have earlier reported partial cloning of a cDNA of a chick atrial myosin heavy chain (MHC) gene, CCSV2 and its expression pattern in embryonic chick hearts (Oana et al (1995) Eur J Cell Biol 67, 42-49). In this study, five overlapping cDNA clones (including CCSV2) which together encode the entire open reading frame of the chick atrial MHC gene were characterized, and both the entire nucleotide sequence consisting of 5825 bases and the deduced amino acid sequence consisting of 1931 amino acids determined. Reinvestigation of the nucleotide sequence of the previously reported and presumably different chick atrial specific MHC cDNA clone, AMHC1 (Yutzey et al (1994) Development 120, 871-883), revealed that our clone and AMHC1 encoded the same MHC. The chick atrial MHC gene was strongly expressed in developing chick atria from a very early stage (Hamburger and Hamilton stage 9, 29-33 h) to the adult stage. This gene was also expressed, although weakly, in the ventricle, somite (the precursor to skeletal muscle) and skeletal muscle during embryonic stages but not in adults. 相似文献
105.
Sohee Shin Shinichi Demura Tsuneo Watanabe Tamotsu Yabumoto Jae-Hyun Lee Naoki Sakakibara Toshio Matsuoka 《Journal of physiological anthropology》2015,34(1)
Background
This study aims to examine age-related and obstacle height-related differences in movements while stepping over obstacles.Methods
The participants included 16 elderly and nine young women. Obstacles that were either 5 or 20 cm high were positioned at the center of a 4-m walking path. The participants were instructed to walk along the path as quickly as possible. The participants’ movements were analyzed using a three-dimensional motion analysis system that recorded their movements as they walked and stepped over the obstacles.Results and conclusions
Seven joint angles and the distances between the ground and six markers were examined in the initial contact and swing instants of the leading and trailing limbs. In the initial contact instant, the elderly women prepared for stepping with a lower toe height than the young women when stepping over the 20-cm obstacle. Trunk rotation was greater in the young women than in the elderly women. In the swing instant, the elderly women showed greater ankle dorsiflexion and hip adduction angles for the leading limb when stepping over the 20-cm obstacle. They moved the trailing limb with increased ankle dorsiflexion, knee flexion, hip flexion, and foot inversion to ensure that they did not touch the obstacle as they stepped over it. These movement patterns are characteristic of elderly individuals who cannot easily lift their lower limbs because of decreased lower-limb strength. 相似文献106.
Tetsuro Takayama Susumu Okamoto Tadakazu Hisamatsu Makoto Naganuma Katsuyoshi Matsuoka Shinta Mizuno Rieko Bessho Toshifumi Hibi Takanori Kanai 《PloS one》2015,10(6)
Cytoapheresis (CAP) therapy is widely used in ulcerative colitis (UC) patients with moderate to severe activity in Japan. The aim of this study is to predict the need of operation after CAP therapy of UC patients on an individual level using an artificial neural network system (ANN). Ninety UC patients with moderate to severe activity were treated with CAP. Data on the patients’ demographics, medication, clinical activity index (CAI) and efficacy of CAP were collected. Clinical data were divided into training data group and validation data group and analyzed using ANN to predict individual outcomes. The sensitivity and specificity of predictive expression by ANN were 0.96 and 0.97, respectively. Events of admission, operation, and use of immunomodulator, and efficacy of CAP were significantly correlated to the outcome. Requirement of operation after CAP therapy was successfully predicted by using ANN. This newly established ANN strategy would be used as powerful support of physicians in the clinical practice. 相似文献
107.
Shin-ichi Takenaka Shinjiro Kaieda Tomotaka Kawayama Masanobu Matsuoka Yoichiro Kaku Takashi Kinoshita Yuki Sakazaki Masaki Okamoto Masaki Tominaga Katsuya Kanesaki Asako Chiba Sachiko Miyake Hiroaki Ida Tomoaki Hoshino 《Biochemistry and Biophysics Reports》2015
The newly characterized cytokine IL-38 (IL-1F10) belongs to the IL-1 family of cytokines. Previous work has demonstrated that IL-38 inhibited Candida albicans-induced IL-17 production from peripheral blood mononuclear cells. However, it is still unclear whether IL-38 is an inflammatory or an anti-inflammatory cytokine. We generated anti-human IL-38 monoclonal antibodies in order to perform immunohistochemical staining and an enzyme-linked immunosorbent assay. While human recombinant IL-38 protein was not cleaved by recombinant caspase-1, chymase, or PR3 in vitro, overexpression of IL-38 cDNA produced a soluble form of IL-38 protein. Furthermore, immunohistochemical analysis showed that synovial tissues obtained from RA patients strongly expressed IL-38 protein. To investigate the biological role of IL-38, C57BL/6 IL-38 gene-deficient (?/?) mice were used in an autoantibody-induced rheumatoid arthritis (RA) mouse model. As compared with control mice, IL-38 (?/?) mice showed greater disease severity, accompanied by higher IL-1β and IL-6 gene expression in the joints. Therefore, IL-38 acts as an inhibitor of the pathogenesis of autoantibody-induced arthritis in mice and may have a role in the development or progression of RA in humans. 相似文献
108.
The function of GABA in the adrenal medulla is still controversial. We will review experimental results in vivo and in vitro
in adrenal chromaffin cells of various mammals to clarify what has been elucidated and what still remains to be settled. 相似文献
109.
Duane L. Guernsey Haiyan Jiang Karen Bedard Susan C. Evans Meghan Ferguson Makoto Matsuoka Christine Macgillivray Mathew Nightingale Scott Perry Andrea L. Rideout Andrew Orr Mark Ludman David L. Skidmore Timothy Benstead Mark E. Samuels 《PLoS genetics》2010,6(8)
Charcot-Marie-Tooth disease (CMT) represents a family of related sensorimotor neuropathies. We studied a large family from a rural eastern Canadian community, with multiple individuals suffering from a condition clinically most similar to autosomal recessive axonal CMT, or AR-CMT2. Homozygosity mapping with high-density SNP genotyping of six affected individuals from the family excluded 23 known genes for various subtypes of CMT and instead identified a single homozygous region on chromosome 9, at 122,423,730–129,841,977 Mbp, shared identical by state in all six affected individuals. A homozygous pathogenic variant was identified in the gene encoding leucine rich repeat and sterile alpha motif 1 (LRSAM1) by direct DNA sequencing of genes within the region in affected DNA samples. The single nucleotide change mutates an intronic consensus acceptor splicing site from AG to AA. Direct analysis of RNA from patient blood demonstrated aberrant splicing of the affected exon, causing an obligatory frameshift and premature truncation of the protein. Western blotting of immortalized cells from a homozygous patient showed complete absence of detectable protein, consistent with the splice site defect. LRSAM1 plays a role in membrane vesicle fusion during viral maturation and for proper adhesion of neuronal cells in culture. Other ubiquitin ligases play documented roles in neurodegenerative diseases. LRSAM1 is a strong candidate for the causal gene for the genetic disorder in our kindred. 相似文献
110.
Eiji Yamamoto Tomonori Takashi Yoichi Morinaka Shaoyang Lin Jianzhong Wu Takashi Matsumoto Hidemi Kitano Makoto Matsuoka Motoyuki Ashikari 《Molecular genetics and genomics : MGG》2010,283(4):305-315
Reproductive isolation plays an important role in speciation as it restricts gene flow and accelerates genetic divergence
between formerly interbreeding population. In rice, hybrid breakdown is a common reproductive isolation observed in both intra
and inter-specific crosses. It is a type of post-zygotic reproductive isolation in which sterility and weakness are manifested
in the F2 and later generations. In this study, the physiological and molecular basis of hybrid breakdown caused by two recessive genes,
hbd2 and hbd3, in a cross between japonica variety, Koshihikari, and indica variety, Habataki, were investigated. Fine mapping of hbd2 resulted in the identification of the causal gene as casein kinase I (CKI1). Further analysis revealed that hbd2-CKI1 allele gains its deleterious function that causes the weakness phenotype by a change of one amino acid. As for the other
gene, hbd3 was mapped to the NBS-LRR gene cluster region. It is the most common class of R-gene that triggers the immune signal in response to pathogen attack. Expression analysis of pathogen response marker genes
suggested that weakness phenotype in this hybrid breakdown can be attributed to an autoimmune response. So far, this is the
first evidence linking autoimmune response to post-zygotic isolation in rice. This finding provides a new insight in understanding
the molecular and evolutionary mechanisms establishing post-zygotic isolation in plants. 相似文献