第二代PCR引物质量评估软件:MFEprimer-2.0,可以针对全基因组数据库在1-3s内预测任意PCR引物对的特异扩增产物和非特异扩增产物: http://biocompute.bmi.ac.cn/CZlab/MFEprimer-2.0/ 该工作已发表在今年6月份的核酸研究(NAR)上,欢迎大家使用该工具,论文参考信息如下: Qu W, Zhou Y, Zhang Y, Lu Y, Wang X, Zhao D, Yang Y, Zhang C* . MFEprimer-2.0: a fast thermodynamics-based program for checking PCR primer specificity. Nucleic Acids Res . 2012 Jul;40(Web Server issue):W205-8. Epub 2012 Jun 11. QuWB 2012 MFEprimer-2.0 NAR.pdf 第一代MFEprimer于2009年发表在Bioinformatics上: Wubin Qu, Zhiyong Shen, Dongsheng Zhao, Yi Yang*, and Chenggang Zhang* . MFEprimer: multiple factor evaluation of the specificity of PCR primers, Bioinformatics , 2009, 25(2):276-278 QuWB 2009 MFEprimer Bioinformatics.pdf 这两篇论文都是由我们实验室 屈武斌 完成的,两篇论文PDF版本均见附件。
How to find the pcr product length, when the primer pairs are known by primer premier 1 F primer Ctrl V as is to get the seq NO 2 R primer Ctrl V reverse complement to get the seq NO and the length 3 the length of pcr product is seq NO(R primer)+ the length(R primer)-seq NO(F primer)
LEAF PCR PROTOCOL (Klimyuk et al., 1993, TPJ 3: 493-494) 1) Samples are harvested in 1.5 ml tubes and stored on ice. 2) 40ul of 0.25N NaOH was added and the samples boiled for 30 sec. 3) 40ul of 0.25N HCl then 20ul Tris mix was added and the samples boiled for another 2 min. -tissue samples can then be used immediatly or stored at 4 C for several weeks. -The amount of tissue used in each PCR reaction should not exceed 2mm2 or the reaction will not work. A small amount of treated material can be excised for use in a PCR reaction with a sterile Gilson tip. PCR reaction conditions are as follows: total volume= 50ul for 5.5 reactions 10X buffer 5ul 27.5uls 10mM dNTPs 1.25uls 6.875uls primer A 2.5uls 13.75uls primer B 2.5uls 13.75uls dH2O 38.75uls 213.1uls taq poly 1.0ul 5.5uls 95 C 10min 1X 95 C 30sec 55 C 30sec 72 C 45sec 30X 72 C 10min 1X run 15ul on a 2% agarose gel note: 2.5 times more primer is used and 2 times more taq polymerase in the leaf PCR protocol. If you could get by with less, Jonathan Jones would have done so! Stocks 0.25N HCl 0.25N NaOH Tris buffer: 0.5M Tris pH 8.0 0.25% Nonidet P-40 LEAF PCR ON ARABIDOPSIS TISSUE WITHOUT ALKALINE TREATMENT Preparation of Master mix: 1 x Taq-buffer 1.5 mM MgCl2 200 mM of each dNTP 1 mM each primer 0.5 ml 20 x Taq polymerase The mix is stored on ice until use. Preparation of leaf tissue: Put the leaf in a small Petri-dish. Make a hole in a leaf with the narrow end of the Pasteur pipette (a forceps might be helpful) and place the leaf in a PCR-tube, if necessary by blowing. On ice, add 50 ml the Master mix. Running the cycles: Transfer the tubes directly from ice to the prewarmed 94 C block on the Robocycler and run the following cycles: 94 C for 3 min 1 x 94 C for 30 s; Tann.* for 1 min; 72 C for 1 min-1 min 30 s 35 x 72 C for 10 min (optional) 1 x Appropriate controls: Positive Negative For screening transgenics: plasmid ColO ColO with endogenous primer-set g DNA gDNA with endogenous primer-set - DNA *The annealing temperature (Tann.) should be 2-3 C below the calculated Tann..
最近我们实验室在BMC Bioinformatics上发表了多重PCR引物设计程序MPprimer,对于提高PCR实验的效率具有一定帮助,有兴趣的朋友可以看看: http://www.biomedcentral.com/1471-2105/11/143/abstract Software MPprimer: a program for reliable multiplex PCR primer design Zhiyong Shen , Wubin Qu , Wen Wang , Yiming Lu , Yonghong Wu , Zhifeng Li , Xingyi Hang , Xiaolei Wang , Dongsheng Zhao and Chenggang Zhang BMC Bioinformatics 2010, 11 : 143 doi:10.1186/1471-2105-11-143 Published: 18March2010 Abstract (provisional) Background Multiplex PCR, defined as the simultaneous amplification of multiple regions of a DNA template or multiple DNA templates using more than one primer set (comprising a forward primer and a reverse primer) in one tube, has been widely used in diagnostic applications of clinical and environmental microbiology studies. However, primer design for multiplex PCR is still a challenging problem and several factors need to be considered. These problems include mis-priming due to nonspecific binding to non-target DNA templates, primer dimerization, and the inability to separate and purify DNA amplicons with similar electrophoretic mobility. Results A program named MPprimer was developed to help users for reliable multiplex PCR primer design. It employs the widely used primer design program Primer3 and the primer specificity evaluation program MFEprimer to design and evaluate the candidate primers based on genomic or transcript DNA database, followed by careful examination to avoid primer dimerization. The graph-expanding algorithm derived from the greedy algorithm was used to determine the optimal primer set combinations (PSCs) for multiplex PCR assay. In addition, MPprimer provides a virtual electrophotogram to help users choose the best PSC. The experimental validation from 2x to 5x plex PCR demonstrates the reliability of MPprimer. As another example, MPprimer is able to design the multiplex PCR primers for DMD (dystrophin gene which caused Duchenne Muscular Dystrophy), which has 79 exons, for 20x, 20x, 20x, 14x, and 5x plex PCR reactions in five tubes to detect underlying exon deletions. Conclusions MPprimer is a valuable tool for designing specific, non-dimerizing primer set combinations with constrained amplicons size for multiplex PCR assays.
(Text adoptedfrom www.protocol-online.org ) I often wondered, why some companies supply their PCR Ingredients with MgCl2 and some with MgSO4. Is there ANY difference between them ? -Fedex- Not much difference, won't affect normal PCR, where the key is the amount of available Mg2+. I think that SO42- might be useeful in methylation PCR, but I am not sure. -bob1- Recipes using Tris-HCl tend to use MgCl2, while recipes employing Tris-SO4/(NH4)2SO4 tend to use MgSO4. -tfitzwater-