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101.
The best-fit environments for the proliferation and differentiation of human adipose tissue-derived stromal cells (hADSCs) may require specific media and stimuli. The characteristics of hADSCs cultured in different media might be different. We evaluated the effects of growth factors on the proliferation and differentiation of hADSCs and compared the effects of these growth factors on hADSCs cultured in different serum-contained media. The effects of kinase inhibitors on the proliferation of hADSCs were also examined. The combination of insulin-transferrin-selenium (ITS) and fibroblast growth factor (FGF) induced the greatest increase in proliferation, while the combination of ITS and epidermal growth factor (EGF) showed the second-greatest effect in the human serum (HS)-contained media. By contrast, in the fetal bovine serum (FBS)-contained media, ITS had little effect while FGF had better results than the combination of ITS and EGF. The inhibitory potency of the kinase inhibitors was different in the two different media. These results suggest that hADSCs may have different characteristics according to the culture conditions, and that extrapolations of results from animal studies, using FBS media, may not correlate to findings in human studies using HS. 相似文献
102.
Previously, we reported that non-steroidal anti-inflammatory drugs (NSAIDs) suppress cellular invasion which was mediated by thrombospondin-1 (TSP-1). As the extending study of the previous observation, we investigated the effect of NSAID-induced TSP-1 on the cellular growth and its related signaling transduction of the TSP-1 production. Among diverse NSAIDs, sulindac sulfide was most potent of inducing the human TSP-1 protein expression. Functionally, induced TSP-1 expression was associated with the growth-compensatory action of NSAID. TSP-1 expression was also elevated by mitogenic signals of ERK1/2 and RhoA GTPase pathway which had also growth-promotive capability after sulindac sulfide treatment. These findings suggest the possible mechanism through which tumor cells can survive the chemopreventive action of NSAIDs or the normal epithelium can reconstitute after NSAID-mediated ulceration in a compensatory way. 相似文献
103.
Autotaxin (ATX) is a strong motogen that can increase invasiveness and angiogenesis. In the present study, we investigated the signal transduction mechanism of ATX-induced tumor cell motility. Unlike N19RhoA expressing cells, the cells expressing N17Cdc42 or N17Rac1 showed reduced motility against ATX. ATX activated Cdc42 and Rac1 and increased complex formation between these small G proteins and p21-activated kinase (PAK). Furthermore, ATX phosphorylated focal adhesion kinase (FAK) that was not shown in cells expressing dominant negative mutants of Cdc42 or Rac1. Collectively, these data strongly indicate that Cdc42 and Rac1 are essential for ATX-induced tumor cell motility in A2058 melanoma cells, and that PAK and FAK might be also involved in the process. 相似文献
104.
N-thiolated beta-lactams: novel antibacterial agents for methicillin-resistant Staphylococcus aureus
Turos E Long TE Konaklieva MI Coates C Shim JY Dickey S Lim DV Cannons A 《Bioorganic & medicinal chemistry letters》2002,12(16):2229-2231
In this report we describe a new family of N-thiolated beta-lactams that have antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). The compounds show unprecedented structure-activity features and an unusual mode of action for a beta-lactam antibiotic. 相似文献
105.
106.
A haplotype map of allohexaploid wheat reveals distinct patterns of selection on homoeologous genomes 总被引:1,自引:0,他引:1
Katherine W Jordan Shichen Wang Yanni Lun Laura-Jayne Gardiner Ron MacLachlan Pierre Hucl Krysta Wiebe Debbie Wong Kerrie L Forrest IWGS Consortium Andrew G Sharpe Christine HD Sidebottom Neil Hall Christopher Toomajian Timothy Close Jorge Dubcovsky Alina Akhunova Luther Talbert Urmil K Bansal Harbans S Bariana Matthew J Hayden Curtis Pozniak Jeffrey A Jeddeloh Anthony Hall Eduard Akhunov 《Genome biology》2015,16(1)
BackgroundBread wheat is an allopolyploid species with a large, highly repetitive genome. To investigate the impact of selection on variants distributed among homoeologous wheat genomes and to build a foundation for understanding genotype-phenotype relationships, we performed population-scale re-sequencing of a diverse panel of wheat lines.ResultsA sample of 62 diverse lines was re-sequenced using the whole exome capture and genotyping-by-sequencing approaches. We describe the allele frequency, functional significance, and chromosomal distribution of 1.57 million single nucleotide polymorphisms and 161,719 small indels. Our results suggest that duplicated homoeologous genes are under purifying selection. We find contrasting patterns of variation and inter-variant associations among wheat genomes; this, in addition to demographic factors, could be explained by differences in the effect of directional selection on duplicated homoeologs. Only a small fraction of the homoeologous regions harboring selected variants overlapped among the wheat genomes in any given wheat line. These selected regions are enriched for loci associated with agronomic traits detected in genome-wide association studies.ConclusionsEvidence suggests that directional selection in allopolyploids rarely acted on multiple parallel advantageous mutations across homoeologous regions, likely indicating that a fitness benefit could be obtained by a mutation at any one of the homoeologs. Additional advantageous variants in other homoelogs probably either contributed little benefit, or were unavailable in populations subjected to directional selection. We hypothesize that allopolyploidy may have increased the likelihood of beneficial allele recovery by broadening the set of possible selection targets.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-015-0606-4) contains supplementary material, which is available to authorized users. 相似文献107.
108.
109.
Molecular analysis of rice plants harboring an Ac/Ds transposable element-mediated gene trapping system 总被引:19,自引:0,他引:19
Hang Gyeong Chin Mi Sook Choe Sung-Ho Lee Sung Han Park Su Hyun Park Ja Choon Koo No Youl Kim Jeung Joo Lee Byeong Geun Oh Gi Hwan Yi Soon Chul Kim Hae Chune Choi Moo Je Cho Chang-deok Han 《The Plant journal : for cell and molecular biology》1999,19(5):615-623
In rice, limited efforts have been made to identify genes by the use of insertional mutagens, especially heterologous transposons such as the maize Ac/Ds. We constructed Ac and gene trap Ds vectors and introduced them into the rice genome by Agrobacterium-mediated transformation. In this report, rice plants that contained single and simple insertions of T-DNA were analysed in order to evaluate the gene-tagging efficiency. The 3' end of Ds was examined for putative splicing donor sites. As observed in maize, three splice donor sites were identified at the 3' end of the Ds in rice. Nearly 80% of Ds elements were excised from the original T-DNA sites, when Ac cDNA was expressed under a CaMV 35S promoter. Repetitive ratoon culturing was performed to induce new transpositions of Ds in new plants derived from cuttings. About 30% of the plants carried at least one Ds which underwent secondary transposition in the later cultures. Eight per cent of transposed Ds elements expressed GUS in various tissues of rice panicles. With cloned DNA adjacent to Ds, the genomic complexities of the insertion sites were examined by Southern hybridization. Half of the Ds insertion sites showed simple hybridization patterns which could be easily utilized to locate the Ds. Our data demonstrate that the Ac/Ds-mediated gene trap system could prove an excellent tool for the analysis of functions of genes in rice. We discuss genetic strategies that could be employed in a large scale mutagenesis using a heterologous Ac/Ds family in rice. 相似文献