📄 eprimer3.ihelp
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Standard (Mandatory) qualifiers: [-sequence] seqall The sequence from which to choose primers. The sequence must be presented 5' to 3' [-outfile] outfile [*.eprimer3] Whitehead primer3_core program output file Additional (Optional) qualifiers (* if not always prompted): -[no]primer toggle [Y] Tell EPrimer3 to pick primer(s)* -task menu [1] Tell EPrimer3 what task to perform. Legal values are 1: 'Pick PCR primers', 2: 'Pick forward primer only', 3: 'Pick reverse primer only', 4: 'No primers needed'. (Values: 1 (Pick PCR primers); 2 (Pick forward primer only); 3 (Pick reverse primer only); 4 (No primers needed)) -hybridprobe toggle [N] An 'internal oligo' is intended to be used as a hybridization probe (hyb probe) to detect the PCR product after amplification.* -oligomishyblibraryfile infile Similar to MISPRIMING-LIBRARY, except that the event we seek to avoid is hybridization of the internal oligo to sequences in this library rather than priming from them. The file must be in (a slightly restricted) FASTA format (W. B. Pearson and D.J. Lipman, PNAS 85:8 pp 2444-2448 [1988]); we briefly discuss the organization of this file below. If this parameter is specified then EPrimer3 locally aligns each candidate oligo against each library sequence and rejects those primers for which the local alignment score times a specified weight (see below) exceeds INTERNAL-OLIGO-MAX-MISHYB. (The maximum value of the weight is arbitrarily set to 12.0.) Each sequence entry in the FASTA-format file must begin with an 'id line' that starts with '>'. The contents of the id line is 'slightly restricted' in that EPrimer3 parses everything after any optional asterisk ('*') as a floating point number to use as the weight mentioned above. If the id line contains no asterisk then the weight defaults to 1.0. The alignment scoring system used is the same as for calculating complementarity among oligos (e.g. SELF-ANY). The remainder of an entry contains the sequence as lines following the id line up until a line starting with '>' or the end of the file. Whitespace and newlines are ignored. Characters 'A', 'T', 'G', 'C', 'a', 't', 'g', 'c' are retained and any other character is converted to 'N' (with the consequence that any IUB / IUPAC codes for ambiguous bases are converted to 'N'). There are no restrictions on line length. An empty value for this parameter indicates that no library should be used. -numreturn integer [5] The maximum number of primer pairs to return. Primer pairs returned are sorted by their 'quality', in other words by the value of the objective function (where a lower number indicates a better primer pair). Caution: setting this parameter to a large value will increase running time. (Integer 0 or more) -includedregion range [(full sequence)] A sub-region of the given sequence in which to pick primers. For example, often the first dozen or so bases of a sequence are vector, and should be excluded from consideration. The value for this parameter has the form (start),(end) where (start) is the index of the first base to consider, and (end) is the last in the primer-picking region. -target range [(full sequence)] If one or more Targets is specified then a legal primer pair must flank at least one of them. A Target might be a simple sequence repeat site (for example a CA repeat) or a single-base-pair polymorphism. The value should be a space-separated list of (start),(end) pairs where (start) is the index of the first base of a Target, and (end) is the last E.g. 50,51 requires primers to surround the 2 bases at positions 50 and 51. -excludedregion range [(full sequence)] Primer oligos may not overlap any region specified in this tag. The associated value must be a space-separated list of (start),(end) pairs where (start) is the index of the first base of the excluded region, and and (end) is the last. This tag is useful for tasks such as excluding regions of low sequence quality or for excluding regions containing repetitive elements such as ALUs or LINEs. E.g. 401,407 68,70 forbids selection of primers in the 7 bases starting at 401 and the 3 bases at 68. -forwardinput string The sequence of a forward primer to check and around which to design reverse primers and optional internal oligos. Must be a substring of SEQUENCE. (Any string is accepted) -reverseinput string The sequence of a reverse primer to check and around which to design forward primers and optional internal oligos. Must be a substring of the reverse strand of SEQUENCE. (Any string is accepted)* -gcclamp integer [0] Require the specified number of consecutive Gs and Cs at the 3' end of both the forward and reverse primer. (This parameter has no effect on the internal oligo if one is requested.) (Integer 0 or more)* -osize integer [20] Optimum length (in bases) of a primer oligo. EPrimer3 will attempt to pick primers close to this length. (Integer 0 or more)* -minsize integer [18] Minimum acceptable length of a primer. Must be greater than 0 and less than or equal to MAX-SIZE. (Integer 1 or more)* -maxsize integer [27] Maximum acceptable length (in bases) of a primer. Currently this parameter cannot be larger than 35. This limit is governed by the maximum oligo size for which EPrimer3's melting-temperature is valid. (Integer up to 35)* -otm float [60.0] Optimum melting temperature(Celsius) for a primer oligo. EPrimer3 will try to pick primers with melting temperatures are close to this temperature. The oligo melting temperature formula in EPrimer3 is that given in Rychlik, Spencer and Rhoads, Nucleic Acids Research, vol 18, num 12, pp 6409-6412 and Breslauer, Frank, Bloeker and Marky, Proc. Natl. Acad. Sci. USA, vol 83, pp 3746-3750. Please refer to the former paper for background discussion. (Any numeric value)* -mintm float [57.0] Minimum acceptable melting temperature(Celsius) for a primer oligo. (Any numeric value)* -maxtm float [63.0] Maximum acceptable melting temperature(Celsius) for a primer oligo. (Any numeric value)* -maxdifftm float [100.0] Maximum acceptable (unsigned) difference between the melting temperatures of the forward and reverse primers. (Any numeric value)* -ogcpercent float [50.0] Primer optimum GC percent. (Any numeric value)* -mingc float [20.0] Minimum allowable percentage of Gs and Cs in any primer. (Any numeric value)* -maxgc float [80.0] Maximum allowable percentage of Gs and Cs in any primer generated by Primer. (Any numeric value)* -saltconc float [50.0] The millimolar concentration of salt (usually KCl) in the PCR. EPrimer3 uses this argument to calculate oligo melting temperatures. (Any numeric value)* -dnaconc float [50.0] The nanomolar concentration of annealing oligos in the PCR. EPrimer3 uses this argument to calculate oligo melting temperatures. The default (50nM) works well with the standard protocol used at the Whitehead/MIT Center for Genome Research--0.5 microliters of 20 micromolar concentration for each primer oligo in a 20 microliter reaction with 10 nanograms template, 0.025 units/microliter Taq polymerase in 0.1 mM each dNTP, 1.5mM MgCl2, 50mM KCl, 10mM Tris-HCL (pH 9.3) using 35 cycles with an annealing temperature of 56 degrees Celsius. This parameter corresponds to 'c' in Rychlik, Spencer and Rhoads' equation (ii) (Nucleic Acids Research, vol 18, num 12) where a suitable value (for a lower initial concentration of template) is 'empirically determined'. The value of this parameter is less than the actual concentration of oligos in the reaction because it is the concentration of annealing oligos, which in turn depends on the amount of template (including PCR product) in a given cycle. This concentration increases a great deal during a PCR; fortunately PCR seems quite robust for a variety of oligo melting temperatures. See ADVICE FOR PICKING PRIMERS. (Any numeric
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