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1.
Morley S. Muralitharan Reinhard F. M. Van Steveninck Stephen E Chandler 《Plant cell reports》1990,9(3):151-155
Non-selected and sodium chloride selected callus lines of Vacdnium corymbosum L.cv Blue Crop and cv. Denise Blue were grown on media supplemented with 0–100 mM NaCl. For both cultivars, fresh weight and dry weight yields were greater in selected lines on all levels of NaCl. Selected lines of Blue Crop displayed better growth than selected lines of Denise Blue at most concentrations of NaCl. Internal Na+ and Cl– concentrations in selected and non-selected lines of both cultivars increased as external concentration was raised. However, selected lines of Blue Crop and Denise Blue accumulated more Na+ and Cl– than non-selected lines. Selected lines of both cultivars maintained higher levels of K+ than non-selected lines on all external NaCl levels. Selected lines of Blue Crop had higher levels of Na+ and Cl– than that of Denise Blue. The results suggest Na+ and Cl– accumulation could be a mechanism allowing better growth in selected lines at moderate salinity levels (50–75 mM NaCl). 相似文献
2.
There are two highly homologous survival motor neuron (SMN) genes in humans but molecular defects in the SMN1 gene cause spinal muscular atrophy (SMA). More than 90% of SMA patients are shown to have a homozygous deletion of exon 7 in the SMN1 gene. Therefore, a simple test for exon 7 deletion would be very useful in the molecular diagnosis of SMA. However, limited methods are available, and most of these methods utilize expensive instruments and consumables. Here, we describe a simple allele-specific PCR test, which can be performed using standard equipment in DNA laboratories. The principle of the test is based on a single nucleotide difference (C versus T) between the exon 7 of SMN1 and SMN2 genes. Using allele-specific primers, two PCR amplifications are performed for each sample to amplify a 404-bp diagnostic fragment, and consequent electrophoresis of PCR products on agarose gel provides definitive information concerning the exon 7 deletion To rule out false negatives, a 500-bp fragment from the N-acetyltransferase gene was coamplified as an internal control in each test. We have, so far, analyzed 41 SMA samples with our method, and tested the validity of results using an independent restriction fragment length polymorphism (RFLP) method. Genotyping results obtained by both methods were in complete agreement for all of the samples analyzed. Our method can also be used to detect heterozygous deletion of exon 7 in SMN genes, if the relative intensities of the diagnostic and internal control bands are determined. 相似文献
3.
Ewa Ostrowska Morley Muralitharan Stephen Chandler Peter Volker Sandra Hetherington Robin Mitra Frank Dunshea 《In vitro cellular & developmental biology. Plant》1998,34(3):225-230
Summary
Pinus radiata is the most important softwood plantation species in Australia and New Zealand. The improtance of this species in forestry
has led to an increasing demand to improve the efficiency of selection time of the production population, which currently
takes 13 yr by traditional methods. With the application of molecular biology techniques such as random amplified polymorphic
DNA (RAPD) the selection period can be reduced to 6 yr. In this study, the conditions for RAPD were optimized and the feasibility
of this marker system was investigated with different families ofPinus radiata from Tasmania and South Australia. Best concentrations of Taq-polymerase (1 U), magnesium chloride (2 mM), and template DNA (20 ng) were selected to test different polymerase chain reaction (PCR) thermocycler profiles. Devey's
et al. (1996) program was the most effective for production of clear RAPD bands. Best conditions were investigated to screen
10–12 bp arbitrary Breasatec and Operon primers. Both types were found useful at detecting genetic variation between families.
Seventy percent and thirty percent of the selected Bresatec and Operon primers, respectively, produced polymorphic bands. 相似文献
4.
Crowley Tamsyn M. Muralitharan Morley S. Stevenson Trevor W. 《Plant Molecular Biology Reporter》2003,21(1):97-97
Genomic DNA was isolated from frozen needles of maturePinus radiata clones using a modified extraction technique incorporating cetyltrimethylammonium bromide (CTAB) for cell lysis. A high sodium
chloride concentration (2 M) was used at 2 stages of the extraction procedure to eradicate polysaccharides, yielding pure
genomic DNA suitable for restriction enzyme digestion and PCR amplification. Extractions were scaled down to suit 1.5-mL Eppendorf
tubes, allowing easier handling and enhanced sterility. 相似文献
5.
RNA interference (RNAi) mediated by DNA-based expression of short hairpin RNA (shRNA) is a powerful method of sequence-specific gene knockdown. A number of vectors for expression of shRNA have been developed that feature promoters from RNA polymerase III (pol III)-transcribed genes of mouse or human origin. To advance the use of RNAi as a tool for functional genomic research and for future development of specific therapeutics in the bovine species, we have developed shRNA expression vectors that feature novel bovine RNA pol III promoters. We characterized two bovine U6 small nuclear RNA (snRNA) promoters (bU6-2 and bU6-3) and a bovine 7SK snRNA promoter (b7SK). We compared the efficiency of each of these promoters to express shRNA molecules. Promoter activity was measured in the context of RNAi by targeting and suppressing the reporter gene encoding enhanced green fluorescent protein. Results show that the b7SK promoter induced the greatest level of suppression in a range of cell lines. The comparison of these bovine promoters in shRNA expression is an important component for the future development of bovine-specific RNAi-based research. 相似文献
6.
7.
Muthukannan Satheesh Kumar Gangatharan Muralitharan Nooruddin Thajuddin 《Biotechnology letters》2009,31(12):1863-1866
Hypersaline Phormidium strains were grown in media amended with naphthalene and anthracene. Phormidium tenue was identified as tolerating and effectively degrading polycyclic aromatic hydrocarbons that may be toxic in the environment.
GC/MS analysis explained the degradation of these compounds by P. tenue. A dioxygenase enzyme system was evident by the formation of anthracene dione as the first degradation compound. This strain
could be used for bioremediation of polycyclic aromatic hydorcarbon pollution on seashores. 相似文献
8.
PCR amplification techniques viz., repetitive DNA element PCR (REP-PCR), short tandemly repeated repetitive PCR (STRR-PCR)
and arbitrarily primed PCR (RAPD-PCR) were used for the taxonomic discrimination among the strains of the unicellular cyanobacterium
Synechococcus elongatus collected across the coastal regions of the Indian subcontinent. These strains showed similar phenotypic and genotypic characteristics.
Data obtained from genomic fingerprinting were used to perform cluster analysis and demonstrated ability to differentiate
strains at intra-specific level. Polymorphisms of different PCR amplification products can serve as strain-specific molecular
fingerprints. In comparison with the STRR and RAPD, the REP primer set generates fingerprints of lower complexity, but still
the phenogram clearly differentiated the strains. In conclusion, described PCR fingerprinting methods can be considered as
promising tools for the differentiation at the strain level of cyanobacteria from the same species. 相似文献
9.
Paramasivan M Sankaran G Sethuraman N Devadoss DS Thangavelu S Gangatharan M 《Bioinformation》2011,5(10):410-415
Helicobacter pylori is the major causative agent of Gastric carcinoma. Significance of the urease accessory interaction proteins are emphasized in colonization of human gastric mucosa and efficient infection of H. pylori. Here an attempt is made to explore the structure and properties of urease accessory interaction proteins from Helicobacter pylori J 99. The proteins chosen for the study are ureH, ureI, nikR, groL and flgS based on the interaction map available from STRING database. The above mentioned proteins do not have a comprehensive three dimensional structure. Hence the models were generated using PSI-BLAST (Position Specific Iterative-Blast) and MODELLER 9V8. Physicochemical characterization encompasses pI, EC, AI, II and GRAVY. Secondary structure was predicted using PSI-PRED. Functional characterization was done by SOSUI and DISULFIND Servers and refinement of structure was done using Ramachandran plot analysis. RMS-Z values were calculated using Q-MEAN Server and CHIMERA was used for molecular simulation studies. Plant defensins from Vigna radiata are successfully docked to the modeled structures and thus interaction could be possibly prevented. These results will pave way for further selective inhibition of H. pylori colonization and in vivo survival by employing plant defensins from Vigna radiata (VrD1 & VrD2). The work will prove that plant defensins provides anticancer relief too. 相似文献
10.
Self-splicing group I introns in tRNA anticodon loops have been found in diverse groups of bacteria. In this work, we identified tRNAfMet group I introns in six strains of marine Synechococcus elongatus. Introns with sizes around 280 bp were consistently obtained in all the strains tested. In a phylogenetic analysis using the nucleotide sequence determined in this study with other cyanobacterial tRNAfMet and tRNALeu intron sequences, the Synechococcus sequence was grouped together with the sequences from other unicellular cyanobacterial strains. Interestingly, the phylogenetic tree inferred from the intronic sequences clearly separates the different tRNA introns, suggesting that each family has its own evolutionary history. 相似文献