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Kinfold(1)			       RNA			      Kinfold(1)

NAME
     Kinfold - Simulate kinetic folding of RNA secondary structures

SYNTAX
     Kinfold [OPTIONS] < input

DESCRIPTION
     The  program  Kinfold  simulates the stochastic folding kinetics of RNA se-
     quences into secondary structures. Folding trajectories are simulated using
     a Monte Carlo procedure using the formation, and dissociation of individual
     base pairs, and (optionally) the shifting of individual base pairs. For the
     energy evaluation of RNA secondary structures  Kinfold  uses routines  from
     the  Vienna RNA Package.
     Input  is	read from stdin and consists of an RNA sequence, optionally fol-
     lowed by  the  initial  structure	and  one  or  more  stop  structures  in
     dot-bracket notation.
     Output  consists  of trajecotires (written to stdout) as well as a log file
     containing summary information for each trajectory.

OPTIONS
     Move set options

     --noShift
	    turn of shift moves.

     --noLP
	    forbid structures containing isolated base-pairs

     Simulation options

     --num  Number of trajectories to compute (default=1).

     --time<tmax>
	    Set maximum length of folding trajectory. The default (500) is  very
	    short and meant for testing purposes only.

     --grow <rate>
	    Simulate folding during transcription with a chain growth event tak-
	    ing place every  rate timesteps.

     --glen <len>
	    Start a folding during transcription simulation with an inital chain
	    length of len.

     --fpt  Toggles  between  first passage time calculations that end as soon a
	    stop struicture is reached and open-ended simulations. Since the de-
	    fault is "first passage time", i.e. using the --fpt switches to open
	    ended simulation.

     --start
	    Read a start conformation from stdin, otherwise the  open  chain  is
	    used as start structures.

     --stop
	    Read  one  or  more  stop  structures  from stdin, otherwise the MFE
	    structure is used.

     --met  Use the Metropolis rule for rate between two  neighboring  conforma-
	    tions,  i.e.  k=min{1,exp(-dE/RT)}. By default Kinfold uses the sym-
	    metric Kawasaki rule k=exp(-dE/2RT).

     --seed<string>
	    Specify the random number seed for the simulation. The  seed  string
	    consists  of   three  numbers  separated  by  an  equal  sign,  e.g.
	    123=456=789. If no seed is specified it is derived from  the  system
	    clock at program start.

     Output options

     -v or --verbose
	    Print more information to stdout.

     -q or --silent
	    Do not write trajectories to stdout.

     --lmin
	    Don't print complete trajectory, but only local minimas encountered.

     --cut<energy>
	    Print only those parts of the trajectory that stays below energy.

     --log<file>
	    Set the log file to file.log. Default "kinout".

     Energy model see e.g. the Vienna RNA documentation for details

     --dangles<int>
	    Select dangling end model. Possible values "0" (none), "1" (normal),
	    "2" (simplified)

     --T, --Temp<temp>
	    Set simulation temperature to temp degrees centigrade.

     -P, --Par <filename>
	    read energy-parameters from filename.

     --logML
	    use logarithmic multiloop energies instead of linear. Default is on,
	    i.e. using --logML switches log energies off.

     Generic options

     --help
	    Output help information and exit.

     --version
	    Output version information and exit.

EXAMPLES
     default  mode:  Start structure is open chain, stop structure is MFE struc-
     ture.  The example output below is a possible trajectory for  the	sequence
     ACUGAUCGUAGUCAC.

	Kinfold --time 100000 < seq.in
	...............   0.00	    2.660
	....(......)...   4.80	    2.664
	...((......))..   0.70	    2.760
	..(((......))).   0.20	    3.407
	..((((....)))).  -0.60	    3.579 X1

     The  trajectory  lists stucture, energy, and time for each simulation step.
     The X1 signifies that the trajectory terminated in the  first  stop  struc-
     ture.   In addition the logfile kinout.log would contain information needed
     to reproduce the simulation results such as options and random seeds used.

	#Date: Tue Oct	7 10:24:27 2008
	#EnergyModel: dangle=2 Temp=37.0 logML=logarithmic Par=(null)
	#MoveSet: noShift=off noLP=off
	#Simulation: num=2 time=500.00 seed=clock fpt=on mc=Kawasaki
	#Simulation: phi=1 pbounds=0.1 0.1 2
	#Output: log=kinout silent=off lmin=off cut=20.00
	#ACUGAUCGUAGUCAC
	#............... (  0.00)
	#..((((....)))). ( -0.60) X01
	(20773	2191 29311) X01        3.579
	( 7439 25635 52414)

     Note that all times are given in internal units that can be translated into
     real time only by copmparison with experiment. Very roughly one  time  step
     corresponds to about 1e-7 seconds.

     To run a folding during transcription simulation use the --grow option. As-
     suming a transcription rate of 100 nt/sec and 1 sec about 1e7 time steps we
     could use

	Kinfold --grow 100000 --glen 10 < seq.in

AUTHORS
     Christoph Flamm <xtof@tbi.univie.ac.at>
     Ivo Hofacker <ivo@tbi.univie.ac.at>

SEE ALSO
     The Vienna RNA package http://www.tbi.univie.ac.at/~ivo/RNA

Christoph Flamm, Ivo Hofacker	       1.1			      Kinfold(1)

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