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Long-Distance Movement (long-distance + movement)
Selected AbstractsLONG-DISTANCE MOVEMENT OF A PINNIPED NEONATEMARINE MAMMAL SCIENCE, Issue 4 2007Julie K. Young First page of article [source] Soil-Borne Wheat Mosaic Virus (SBWMV) 37 kDa Protein Rescues Cell-to-Cell and Long-Distance Movement of an Immobile Tobacco Mosaic Virus Mutant in Nicotiana benthamiana, a Non-Host of SBWMVJOURNAL OF PHYTOPATHOLOGY, Issue 1 2005C. Zhang Abstract To verify the role and examine the functional range of the 37 kDa putative movement protein (MP) of soil-borne wheat mosaic virus (SBWMV), the 37 kDa gene was inserted into an infectious tobacco mosaic virus (TMV)-based expression vector (p30B), to generate p30BMP. The 30 kDa cell-to-cell MP gene of TMV was then inactivated (in p30BMP to give p30B,MP) by a frameshift mutation which removed 80 amino acids from its C-terminus. Systemic infection of Nicotiana benthamiana plants occurred following inoculation with in vitro transcripts of p30BMP or p30B,MP. Progeny viral RNAs from inoculated and systemically infected leaves were analysed by reverse transcriptase polymerase chain reaction and ApaI digestion, and by sequencing. The 30 kDa TMV MP or its truncated form were detected, respectively, in Western blots of cell wall protein extracts from p30BMP-transcript or p30B,MP-transcript inoculated or systemically infected N. benthamiana leaves. High levels of SBWMV 37 kDa MP were detected in all cases. The results suggest that the 37 kDa protein of SBWMV, a monocotyledonous-infecting furovirus, can complement both cell-to-cell and long-distance movement functions in a defective heterologous virus (TMV) in N. benthamiana, a non-host of SBWMV. [source] Inhibited Long-Distance Movement of Potato Leafroll Virus to Tubers in Potato Genotypes Expressing Combined Resistance to Infection, Virus Multiplication and AccumulationJOURNAL OF PHYTOPATHOLOGY, Issue 9 2003J. Syller Abstract Plants of two potato clones which, in preliminary greenhouse assessments, showed resistance to multiplication and accumulation of potato leafroll virus (PLRV) were graft or aphid inoculated with the virus and grown in the greenhouse; plants of a moderately susceptible cultivar were used for comparison in all experiments. A high concentration of aphid-borne inoculum was used to ensure strong infection pressure. Clone M62759 appeared to be highly resistant to PLRV infection, whereas clone PS1706 was more susceptible. Both clones expressed a high level of resistance to virus multiplication, when primary or secondary infection was assayed by enzyme-linked immunosorbent assay. Moreover, PLRV was detected in only few or none of the progeny plants of clone M62759, which thus strongly inhibited virus transport to tubers. The study on PLRV translocation from aphid-inoculated shoots to uninoculated shoots sprouted from the same tubers showed that no specific mechanisms are likely to impair PLRV movement through the tubers of the resistant genotypes. These results indicate that three valuable components of the resistance to PLRV are probably closely linked in the genotype, a combination that seems to occur rather rarely in potato clones. Nevertheless, selecting potato genotypes for the complex resistance to PLRV may prove to be a worthwhile part of breeding programmes, provided that the genetic mechanisms governing particular types of resistance are better recognized. [source] Long-distance movements of the grey-headed flying fox (Pteropus poliocephalus)JOURNAL OF ZOOLOGY, Issue 2 2004Christopher R. Tidemann Abstract The grey-headed flying fox Pteropus poliocephalus, a nationally vulnerable species, is endemic to coastal eastern Australia, from Maryborough, Queensland, through New South Wales to Melbourne, Victoria. Pteropus poliocephalus forages at night, primarily on eucalypt blossom within 50 km of traditional camps (day roosts), usually in dense, riparian vegetation. Several attempts have been made to track long-distance movements of P. poliocephalus across its extensive and climatically highly variable range, but the technology has been inadequate for tracking at the required speed and scale. Satellite tracking was used to monitor movements of a 2-year-old male P. poliocephalus, trapped at the Currie Park camp in the north of the species' range (28°48,S) from January 2000, and another from its most southerly camp, Melbourne (37°50,S), from April 2000. The first flying fox moved camp 50 km noth-east to Dallas Park, where it stayed until March, then transited at least 15 other camps between 28°12,,32°44,S, before returning to Dallas Park in September. The second flying fox remained in Melbourne until July, then transited at least six other camps to 33°44,S, before returning to Melbourne in January 2001. Both animals made round trips of at least 2000 km, traversing >4° latitude, before returning to their camps of origin, while other animals remained. The study suggests that P. poliocephalus is a partial migrant that uses winds to facilitate long-distance movements, and underlines the importance of management at a national scale. [source] Incipient speciation of Catostylus mosaicus (Scyphozoa, Rhizostomeae, Catostylidae), comparative phylogeography and biogeography in south-east AustraliaJOURNAL OF BIOGEOGRAPHY, Issue 3 2005Michael N Dawson Abstract Aim, Phylogeography provides a framework to explain and integrate patterns of marine biodiversity at infra- and supra-specific levels. As originally expounded, the phylogeographic hypotheses are generalities that have limited discriminatory power; the goal of this study is to generate and test specific instances of the hypotheses, thereby better elucidating both local patterns of evolution and the conditions under which the generalities do or do not apply. Location, Coastal south-east Australia (New South Wales, Tasmania and Victoria), and south-west North America (California and Baja California). Methods, Phylogeographic hypotheses specific to coastal south-east Australia were generated a priori, principally from existing detailed distributional analyses of echinoderms and decapods. The hypotheses are tested using mitochondrial cytochrome c oxidase subunit I (COI) and nuclear internal transcribed spacer 1 (ITS1) DNA sequence data describing population variation in the jellyfish Catostylus mosaicus, integrated with comparable data from the literature. Results, Mitochondrial COI distinguished two reciprocally monophyletic clades of C. mosaicus (mean ± SD: 3.61 ± 0.40% pairwise sequence divergence) that were also differentiated by ITS1 haplotype frequency differences; the boundary between the clades was geographically proximate to a provincial zoogeographic boundary in the vicinity of Bass Strait. There was also limited evidence of another genetic inhomogeneity, of considerably smaller magnitude, in close proximity to a second hypothesized zoogeographic discontinuity near Sydney. Other coastal marine species also show genetic divergences in the vicinity of Bass Strait, although they are not closely concordant with each other or with reported biogeographic discontinuities in the region, being up to several hundreds of kilometres apart. None of the species studied to date show a strong phylogeographic discontinuity across the biogeographic transition zone near Sydney. Main conclusions, Patterns of evolution in the Bass Strait and coastal New South Wales regions differ fundamentally because of long-term differences in extrinsic factors. Since the late Pliocene, periods of cold climate and low sea-level segregated warm temperate organisms east or west of an emergent Bassian Isthmus resulting in population divergence and speciation; during subsequent periods of warmer and higher seas, sister taxa expanded into the Bass Strait region leading to weakly correlated phylogeographic and biogeographic patterns. The Sydney region, by contrast, has been more consistently favourable to shifts in species' ranges and long-distance movement, resulting in a lack of intra-specific and species-level diversification. Comparisons between the Sydney and Bass Strait regions and prior studies in North America suggest that vicariance plays a key role in generating coastal biodiversity and that dispersal explains many of the deviations from the phylogeographic hypotheses. [source] RNA commutes to work: regulation of plant gene expression by systemically transported RNA moleculesBIOESSAYS, Issue 12 2001Shoko Ueki Although long-distance movement of endogenous mRNAs in plants is well established, the functional contributions of these transported RNA molecules has remained unclear. In a recent report, Kim et al.2001 showed that systemically transported mRNA is capable of causing phenotypic change in developing tissue. Here, this finding and its significance are reviewed and discussed in detail. In addition, in order to give proper perspective, long-distance transport of other types of RNAs, e.g., RNA elicitors of post-transcriptional gene silencing and RNA genomes of plant viruses, and its possible regulation are discussed. BioEssays 23:1087,1090, 2001. © 2001 John Wiley & Sons, Inc. [source] Long-distance movements of the grey-headed flying fox (Pteropus poliocephalus)JOURNAL OF ZOOLOGY, Issue 2 2004Christopher R. Tidemann Abstract The grey-headed flying fox Pteropus poliocephalus, a nationally vulnerable species, is endemic to coastal eastern Australia, from Maryborough, Queensland, through New South Wales to Melbourne, Victoria. Pteropus poliocephalus forages at night, primarily on eucalypt blossom within 50 km of traditional camps (day roosts), usually in dense, riparian vegetation. Several attempts have been made to track long-distance movements of P. poliocephalus across its extensive and climatically highly variable range, but the technology has been inadequate for tracking at the required speed and scale. Satellite tracking was used to monitor movements of a 2-year-old male P. poliocephalus, trapped at the Currie Park camp in the north of the species' range (28°48,S) from January 2000, and another from its most southerly camp, Melbourne (37°50,S), from April 2000. The first flying fox moved camp 50 km noth-east to Dallas Park, where it stayed until March, then transited at least 15 other camps between 28°12,,32°44,S, before returning to Dallas Park in September. The second flying fox remained in Melbourne until July, then transited at least six other camps to 33°44,S, before returning to Melbourne in January 2001. Both animals made round trips of at least 2000 km, traversing >4° latitude, before returning to their camps of origin, while other animals remained. The study suggests that P. poliocephalus is a partial migrant that uses winds to facilitate long-distance movements, and underlines the importance of management at a national scale. [source] | ||||||||||