Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
KINWALKER(1)			   kinwalker			  KINWALKER(1)

NAME
       kinwalker - predicts RNA	folding	trajectories

SYNOPSIS
       kinwalker   [--help]  [--verbose] [--test] [--interrupt]	[--printfront]
       [--barrier_heuristic=CHAR] [--dangle=INT] [--grouping=STRING] [--looka-
       head=INT] [--maxkeep=INT] [--nolonely=INT] [--transcribed=INT] [--tran-
       scription_rate=INT] [--windowsize=INT]

DESCRIPTION
       The Kinwalker algorithm predicts	RNA  folding  trajectories  and	 first
       passage	times by connecting the	denatured state	with the predicted na-
       tive structure through a	series of intermediate states.

       Kinwalker splits	the folding process into a series of events where each
       event can either	be a folding event or a	transcription event.  In  each
       transcription  event  one base from the RNA sequence is appended	to the
       already transcribed and (partially) folded subsequence. Kinwalker  exe-
       cutes  transcription  events at regular time intervals. In each folding
       event a subsequence of the already transcribed RNA sequence is selected
       and a new structure is formed by	combining base pairs from the  current
       structure  with	base pairs from	the mfE	structure of that subsequence.
       This is done in such a way that the new structure includes  base	 pairs
       from  both  structures in an energetically favorable manner.  Kinwalker
       estimates the waiting times for individual folding events depending  on
       the  height of the energy barrier between the current structure and the
       new structure into which	the molecule is	folded.	Folding	events between
       structures can only occur, if the energy	barrier	between	them  is  less
       than  the  maximum allowed energy barrier. As folding paths can only be
       calculated exhaustively for  short  sequences  (n>100),	heuristic  ap-
       proaches	 have  to be employed which explicitly construct a (re)folding
       path between the	two structures.	The saddle height is then estimated as
       the highest point along the path. The best known	algorithm for approxi-
       mating saddle heights between RNA  conformations	 is  the  Morgan-Higgs
       heuristic,  which tries to find a folding path from an origin secondary
       structure to a target secondary	structure  where  the  maximum	height
       along  the  path	 is minimal. The heuristic models state	transitions at
       base pair resolution.

       Uses the	ViennaRNA package (currently available at  http://www.tbi.uni-
       vie.ac.at/~ivo/RNA/)  for free energy calculations and determination of
       locally optimal substructures.

       Kinwalker reads the RNA sequence	from stdin and returns the  intermedi-
       ate  states of the predicted folding trajectories along with first pas-
       sage times and energy barriers.	 Kinwalker  terminates	when  the  mfE
       structure is reached.

OPTIONS
       Usage: ./kinwalker [OPTIONS] < SeqFile  > Outfile

	      Options without argument:

       -h,--help
	      Print usage information for ./kinwalker.

       --init_structure
	      Start with a structure other than	the open chain.

       --interrupt
	      Allow  interrupted  folding trajectories when the	barrier	is ex-
	      ceeded.

       --printfront
	      Creates PS plots	of  front  progression	with  index  i,	 named
	      front_trajectory($i).ps.

       -t,--test
	      Use test sequence.

       -v,--verbose
	      Verbose mode. Print debugging messages about program progress.

	      Options with argument:

       --barrier_heuristic=CHAR
	      'M'  Morgan-Higgs,'S'  limits small stacks,'B' Barriers,'A' all,
	      then take	minimum. Default: >M<

       --dangle=INT
	      Dangle value of 0,1,2 as in the ViennaRNA	package. Default: >0<

       --grouping=STRING
	      How barrier_heuristic 'M'	treats conflict	 groups("standard"  or
	      "regroup"). Default: >standard<

       --lookahead=INT
	      #BP that MorganHiggs forms its subpaths from. Default: >1<

       --maxkeep=INT
	      Breadth  of  breadth  first search in barrier_heuristic='B'. De-
	      fault: >1<

       --nolonely=INT
	      Value of noLonelyPairs as	in ViennaRNA. Default: >2<

       --transcribed=INT
	      #bases initially transcribed, <0 means all is  transcribed.  De-
	      fault: >1<)

       --transcription_rate=FLOAT
	      #bases transcribed per second. Default: >200<)

       --windowsize=INT
	      Max  size	 of substructures considered for folding events	during
	      transcription, 0=	all are	considered. Default: >0<)

EXAMPLE
       ./kinwalker --transcribed=50 --transcription_rate=80  --barrier_heuris-
       tic=S --interrupt --window_size=100 < hok.seq > hok.out

       Computes	 the  folding trajectory of the	sequence in hok.seq and	writes
       it to hok.out. Folding starts with 50 nucleotide	transcribed at a tran-
       scription rate of 80 nc/sec. Interrupted	trajectories are allowed,  the
       'S'  barrier  heuristic	is used	and only substructures of length up to
       100 nc are considered during transcription (windows_size).

       ./kinwalker  --printfront  < hok.seq > hok.out

       Folds the hok.seq sequence with standard	parameters, printing  interme-
       diate  states  of  the  folding	trajectory  to	successive files named
       front_trajectory1.ps, front_trajectory2.ps, etc.

FILES
       none

DEPENDENCIES
       ViennaRNA package (http://www.tbi.univie.ac.at/~ivo/RNA/)

AUTHOR
       Michael Geis <michael at	bioinf	dot  uni-leipzig  dot  de>,  Christoph
       Flamm

REFERENCES
       S.  R. Morgan and P. G. Higgs. Barrier heights between ground states in
       a model of RNA secondary	structure, J. Phys. A.:	Math. Gen., 31,	 1998,
       3153-3170.

       Christoph  Flamm	and Ivo	L. Hofacker and	Sebastian Maurer-Stroh and Pe-
       ter F. Stadler and Martin Zehl. Design of Multi-Stable  RNA  Molecules,
       RNA, 2000,7, 254-265.

Michael	Geis			      0.1			  KINWALKER(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=kinwalker&sektion=1&manpath=FreeBSD+Ports+14.3.quarterly>

home | help