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991.
992.
Adult-derived stem cells and their potential for use in tissue repair and molecular medicine 总被引:3,自引:0,他引:3
Young HE Duplaa C Katz R Thompson T Hawkins KC Boev AN Henson NL Heaton M Sood R Ashley D Stout C Morgan JH Uchakin PN Rimando M Long GF Thomas C Yoon JI Park JE Hunt DJ Walsh NM Davis JC Lightner JE Hutchings AM Murphy ML Boswell E McAbee JA Gray BM Piskurich J Blake L Collins JA Moreau C Hixson D Bowyer FP Black AC 《Journal of cellular and molecular medicine》2005,9(3):753-769
This report reviews three categories of precursor cells present within adults. The first category of precursor cell, the epiblast-like stem cell, has the potential of forming cells from all three embryonic germ layer lineages, e.g., ectoderm, mesoderm, and endoderm. The second category of precursor cell, the germ layer lineage stem cell, consists of three separate cells. Each of the three cells is committed to form cells limited to a specific embryonic germ layer lineage. Thus the second category consists of germ layer lineage ectodermal stem cells, germ layer lineage mesodermal stem cells, and germ layer lineage endodermal stem cells. The third category of precursor cells, progenitor cells, contains a multitude of cells. These cells are committed to form specific cell and tissue types and are the immediate precursors to the differentiated cells and tissues of the adult. The three categories of precursor cells can be readily isolated from adult tissues. They can be distinguished from each other based on their size, growth in cell culture, expressed genes, cell surface markers, and potential for differentiation. This report also discusses new findings. These findings include the karyotypic analysis of germ layer lineage stem cells; the appearance of dopaminergic neurons after implantation of naive adult pluripotent stem cells into a 6-hydroxydopamine-lesioned Parkinson's model; and the use of adult stem cells as transport mechanisms for exogenous genetic material. We conclude by discussing the potential roles of adult-derived precursor cells as building blocks for tissue repair and as delivery vehicles for molecular medicine. 相似文献
993.
Fragrant Volatile Sesquiterpenoids Isolated from the Essential Oil of Laggera pterodonta by Using Olfactory‐Guided Fractionation 下载免费PDF全文
Chemical composition of the essential oil from Laggera pterodonta (Compositae) was inverstigated. GC/MS Analyses led to the identification of 68 components, representing more than 96% of the total oil. By focusing on the woody note fraction of the essential oil, one new bisabolane‐type sesquiterpenoid, bisabola‐2,7(14),11‐trien‐10‐ol ( 1 ), together with ten known compounds, bisabolol oxide B ( 2 ), ylangenol ( 3 ), copaborneol ( 4 ), guai‐11‐en‐10‐ol ( 5 ), spathulenol ( 6 ), aromadendran‐10‐ol ( 7 ), caryophyllenol ( 8 ), 5α,7α‐eudesm‐11(13)‐en‐4α‐ol ( 9 ), γ‐costic acid ( 10 ), and eudesma‐4(15),11(13)‐diene‐12,5β‐olide ( 11 ), were isolated by using olfactory‐guided fractionation. The structures of the eleven compounds were determined by NMR and MS analyses. All the volatile compounds reported here were isolated for the first time from this plant. On the basis of preliminary odor assessment, the odor of the woody‐note fractions of the essential oil was assumed to be due to these isolated sesquiterpenoids. 相似文献
994.
Abstract The single locus complementary sex determination (sl‐csd) gene is the primary gene determining the gender of honey bees (Apis spp.). While the csd gene has been well studied in the Western honey bee (Apis mellifera), and comparable data exist in both the Eastern honey bee (Apis cerana) and the giant honey bee (Apis dorsata), no studies have been conducted in the red dwarf honey bee, Apis florea. In this study we cloned the genomic region 3 of the A. florea csd gene from 60 workers, and identified 12 csd alleles. Analysis showed that similar to A. mellifera, region 3 of the csd gene contains a RS domain at the N terminal, a proline‐rich domain at the C terminal, and a hypervariable region in the middle. However, the A. florea csd gene possessed a much higher level of nucleotide diversity, compared to A. mellifera, A. cerana and Apis dorsata. We also show that similar to the other three Apis species, in A. florea, nonsynonymous mutations in the csd gene are selectively favored in young alleles. 相似文献
995.
脂氧合酶、茉莉酸和水杨酸对猕猴桃果实后熟软化进程中乙烯生物合成的调控 总被引:12,自引:0,他引:12
20℃下后熟果实的LOX活性增加先于自由基产生和乙烯生成;JA处理对果实后熟软化启动期(采后1d)和果实快速软化期(采后5d)果实切片中的LOX活性、自由基产生和乙烯生物合成有促进作用,至果实软化后期(采后7d)这种效应消失;亚油酸只在采后1d果实切片中促使LOX活性和乙烯生成;SA处理抑制了果实后熟进程中组织切片的LOX活性、自由基产生和乙烯的生物合成;SA和JA对LOX活性和乙烯生物合成具有明显的拮抗作用。 相似文献
996.
Long Li Junfeng Huang Lixia Qin Yuying Huang Wei Zeng Yue Rao Juan Li Xuebao Li Wenliang Xu 《Physiologia plantarum》2014,152(2):367-379
Xylan is the major hemicellulosic constituent in dicot secondary cell walls. Cell wall composition of cotton fiber changes dynamically throughout development. Not only the amounts but also the molecular sizes of the hemicellulosic polysaccharides show substantial changes during cotton fiber development. However, none of the genes encoding glycosyltransferases (GTs) responsible for synthesizing xylan have been isolated and characterized in cotton fiber. In this study, we applied a bioinformatics approach and identified two putative GTs from cotton, designated GhGT43A1 and GhGT43C1, which belong to the CAZy GT43 family and are closely related to Arabidopsis IRX9 and IRX14, respectively. We show that GhGT43A1 is highly and preferentially expressed in 15 and 20 days post‐anthesis (dpa) cotton fiber, whereas GhGT43C1 is ubiquitously expressed in most organs, with especially high expression in 15 dpa fiber and hypocotyl. Complementation analysis demonstrates that GhG43A1 and GhGT43C1 are orthologs of Arabidopsis IRX9 and IRX14, respectively. Furthermore, we show that overexpression of GhGT43A1 or GhGT43C1 in Arabidopsis results in increased xylan content. We also show that overexpression of GhGT43A1 or GhGT43C1 leads to more cellulose deposition. These findings suggest that GhGT43A1 and GhGT43C1 likely participate in xylan synthesis during fiber development. 相似文献
997.
Xuan Chen Long He Miaoze Xu Jin Yang Juan Li Tianye Zhang Qiansheng Liao Hengmu Zhang Jian Yang Jianping Chen 《Molecular Plant Pathology》2021,22(11):1383-1398
The Chinese wheat mosaic virus (CWMV) genome consists of two positive-strand RNAs that are required for CWMV replication and translation. The eukaryotic translation elongation factor (eEF1A) is crucial for the elongation of protein translation in eukaryotes. Here, we show that silencing eEF1A expression in Nicotiana benthamiana plants by performing virus-induced gene silencing can greatly reduce the accumulation of CWMV genomic RNAs, whereas overexpression of eEF1A in plants increases the accumulation of CWMV genomic RNAs. In vivo and in vitro assays showed that eEF1A does not interact with CWMV RNA-dependent RNA polymerase. Electrophoretic mobility shift assays revealed that eEF1A can specifically bind to the 3ʹ-untranslated region (UTR) of CWMV genomic RNAs. By performing mutational analyses, we determined that the conserved region in the 3ʹ-UTR of CWMV genomic RNAs is necessary for CWMV replication and translation, and that the sixth stem-loop (SL-6) in the 3ʹ-UTR of CWMV genomic RNAs plays a key role in CWMV infection. We conclude that eEF1A is an essential host factor for CWMV infection. This finding should help us to develop new strategies for managing CWMV infections in host plants. 相似文献
998.
Analysis of gene-trap Ds rice populations in Korea 总被引:1,自引:0,他引:1
Park SH Jun NS Kim CM Oh TY Huang J Xuan YH Park SJ Je BI Piao HL Park SH Cha YS Ahn BO Ji HS Lee MC Suh SC Nam MH Eun MY Yi G Yun DW Han CD 《Plant molecular biology》2007,65(4):373-384
Insertional mutagen-mediated gene tagging populations have been essential resources for analyzing the function of plant genes.
In rice, maize transposable elements have been successfully utilized to produce transposant populations. However, many generations
and substantial field space are required to obtain a sufficiently sized transposant population. In rice, the japonica and
indica subspecies are phenotypically and genetically divergent. Here, callus cultures with seeds carrying Ac and Ds were used to produce 89,700 lines of Dongjin, a japonica cultivar, and 6,200 lines of MGRI079, whose genome is composed of
a mixture of the genetic backgrounds of japonica and indica. Of the more than 3,000 lines examined, 67% had Ds elements. Among the Ds-carrying lines, 81% of Dongjin and 63% of MGRI079 contained transposed Ds, with an average of around 2.0 copies. By examining more than 15,000 lines, it was found that 12% expressed the reporter
gene GUS during the early-seedling stage. GUS was expressed in root hairs and crown root initials at estimated frequencies
of 0.78% and 0.34%, respectively. The 5,271 analyzed Ds loci were found to be randomly distributed over all of the rice chromosomes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Sung Han Park, Nam Soo Jun, Chul Min Kim are contributed equally to this paper 相似文献
999.
1000.
Wang X Kang GH Campan M Weisenberger DJ Long TI Cozen W Bernstein L Wu AH Siegmund KD Shibata D Laird PW 《PloS one》2011,6(10):e25985