RNALFOLD(1)

NAME
RNALfold - manual page for RNALfold 2.3.1

SYNOPSIS
RNALfold [OPTIONS]...

DESCRIPTION
RNALfold 2.3.1

calculate locally stable secondary structures of RNAs

Compute locally stable RNA secondary structure with a maximal base pair span. For a sequence of length n and a base pair span of L the algorithm uses only O(n+L*L) memory and O(n*L*L) CPU time. Thus it is practical to "scan" very large genomes for short RNA structures. Output consists of a list of secondary structure components of size <= L, one entry per line. Each output line contains the predicted local structure its energy in kcal/mol and the starting position of the local structure.

-h, --help
    Print help and exit

--detailed-help
    Print help, including all details and hidden options, and exit

--full-help
    Print help, including hidden options, and exit

-V, --version
    Print version and exit

  General Options:

    Below are command line options which alter the general behavior of this program

-L, --span=INT
    Set the maximum allowed separation of a base pair to span. I.e. no pairs (i,j) with j-i>span will be allowed.

    (default=`150')

--noconv
    Do not automatically substitude nucleotide "T" with "U"

    (default=off)

-o, --outfile=<filename>
    Print output to file instead of stdout

    Specifying a file name/prefix will print the output into a file instead of stdout. If a FASTA header precedes the input sequence, the appropriate fasta ID is used as infix for the file name. Each generated file will be suffixed with the file extension '.lfold'. If a file with the same filename already exists, any output of the program will be appended to it.

-i, --infile=<filename>
    Read a file instead of reading from stdin

    The default behavior of RNALfold is to read input from stdin. Using this parameter the user can specify an input file name where data is read from.

  Algorithms:

    Select additional algorithms which should be included in the calculations. The Minimum free energy (MFE) and a structure representative are calculated in any case.

-z, --zscore[=DOUBLE]
    Activate z-score computation. An optional argument may be supplied to set the threshold Due to parsing the commandline parameters a negative value should be given immediately after "z" without spaces e.g. -z-4.9

    (default=`-2')

-g, --gquad
    Incoorporate G-Quadruplex formation into the structure prediction algorithm

    (default=off)

  Model Details:

-T, --temp=DOUBLE
    Rescale energy parameters to a temperature of temp C. Default is 37C.

-4, --noTetra
    Do not include special tabulated stabilizing energies for tri-, tetra- and hexaloop hairpins. Mostly for testing.

    (default=off)

-d, --dangles=INT
    How to treat "dangling end" energies for bases adjacent to helices in free ends and multi-loops

    (default=`2')

    With -d1 only unpaired bases can participate in at most one dangling end, this is the default for mfe folding but unsupported for the partition function folding.

    With -d2 this check is ignored, dangling energies will be added for the bases adjacent to a helix on both sides in any case; this is the default for partition function folding (-p). The option -d0 ignores dangling ends altogether (mostly for debugging). With -d3 mfe folding will allow coaxial stacking of adjacent helices in multi-loops. At the moment the implementation will not allow coaxial stacking of the two interior pairs in a loop of degree 3 and works only for mfe folding.

    Note that by default (as well as with -d1 and -d3) pf and mfe folding treat dangling ends differently. Use -d2 in addition to -p to ensure that both algorithms use the same energy model.

--noLP
    Produce structures without lonely pairs (helices of length 1).

    (default=off)

    For partition function folding this only disallows pairs that can only occur isolated. Other pairs may still occasionally occur as helices of length 1.

--noGU
    Do not allow GU pairs

    (default=off)

--noClosingGU
    Do not allow GU pairs at the end of helices

    (default=off)

-P, --paramFile=paramfile
    Read energy parameters from paramfile, instead of using the default parameter set.

    A sample parameter file should accompany your distribution. See the RNAlib documentation for details on the file format.

--nsp=STRING
    Allow other pairs in addition to the usual AU,GC,and GU pairs.

    Its argument is a comma separated list of additionally allowed pairs. If the first character is a "-" then AB will imply that AB and BA are allowed pairs. e.g. RNAfold -nsp -GA will allow GA and AG pairs. Nonstandard pairs are given 0 stacking energy.

-e, --energyModel=INT
    Rarely used option to fold sequences from the artificial ABCD... alphabet, where A pairs B, C-D etc. Use the energy parameters for GC (-e 1) or AU (-e 2) pairs.

REFERENCES
If you use this program in your work you might want to cite: R. Lorenz, S.H. Bernhart, C. Hoener zu Siederdissen, H. Tafer, C. Flamm, P.F. Stadler and I.L. Hofacker (2011), "ViennaRNA Package 2.0", Algorithms for Molecular Biology: 6:26 I.L. Hofacker, W. Fontana, P.F. Stadler, S. Bonhoeffer, M. Tacker, P. Schuster (1994), "Fast Folding and Comparison of RNA Secondary Structures", Monatshefte f. Chemie: 125, pp 167-188 I.L. Hofacker, B. Priwitzer, and P.F. Stadler (2004), "Prediction of Locally Stable RNA Secondary Structures for Genome-Wide Surveys", Bioinformatics: 20, pp 186-190 M. Zuker, P. Stiegler (1981), "Optimal computer folding of large RNA sequences using thermodynamic and auxiliary information", Nucl Acid Res: 9, pp 133-148 J.S. McCaskill (1990), "The equilibrium partition function and base pair binding probabilities for RNA secondary structures", Biopolymers: 29, pp 1105-1119 The energy parameters are taken from: D.H. Mathews, M.D. Disney, D. Matthew, J.L. Childs, S.J. Schroeder, J. Susan, M. Zuker, D.H. Turner (2004), "Incorporating chemical modification constraints into a dynamic programming algorithm for prediction of RNA secondary structure", Proc. Natl. Acad. Sci. USA: 101, pp 7287-7292 D.H Turner, D.H. Mathews (2009), "NNDB: The nearest neighbor parameter database for predicting stability of nucleic acid secondary structure", Nucleic Acids Research: 38, pp 280-282

AUTHOR
Ivo L Hofacker, Peter F Stadler, Ronny Lorenz

REPORTING BUGS
If in doubt our program is right, nature is at fault. Comments should be sent to rna@tbi.univie.ac.at.

SEE ALSO
RNAplfold(1)