chaos

 

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Function

Draw a chaos game representation plot for a nucleotide sequence

Description

chaos creates a chaos game representation (CGR) plot for a nucleotide sequence. A CGR plot represents a nucleotide sequence as a square box with an A, G, C, or T nucleotide at each corner. The box contains dots, each one representing a dinucleotide. All overlapping dinucleotides from the start to the end of the sequence are plotted. Regions which are devoid of dots (or heavily covered with dots) indicate short sequence motifs that are unusually infrequent (or frequent). CGR plots depict base composition and sequentiality and is a unique visual representation of a sequence that complements more traditional linear representations.

Algorithm

The plot is generated as follows. A box is drawn and an A, G, C, or T is drawn at each corner. Starting from the middle, move half way to the corner of the box representing the first base in the sequence and draw a dot. Then for each subsequent base move half way to the corresponding box corner and draw a dot. Finally display the number and percentage values of AGCT bases. The result is an image of a square sprinkled with dots.

Usage

Here is a sample session with chaos 


% chaos tembl:j01636 -graph cps 
Draw a chaos game representation plot for a nucleotide sequence

Created chaos.ps

Go to the input files for this example
Go to the output files for this example

Command line arguments 

Draw a chaos game representation plot for a nucleotide sequence
Version: EMBOSS:6.6.0.0

   Standard (Mandatory) qualifiers:
  [-sequence]          sequence   Nucleotide sequence filename and optional
                                  format, or reference (input USA)
   -graph              graph      [$EMBOSS_GRAPHICS value, or x11] Graph type
                                  (ps, hpgl, hp7470, hp7580, meta, cps, x11,
                                  tek, tekt, none, data, xterm, png, gif, pdf,
                                  svg)

   Additional (Optional) qualifiers: (none)
   Advanced (Unprompted) qualifiers: (none)
   Associated qualifiers:

   "-sequence" associated qualifiers
   -sbegin1            integer    Start of the sequence to be used
   -send1              integer    End of the sequence to be used
   -sreverse1          boolean    Reverse (if DNA)
   -sask1              boolean    Ask for begin/end/reverse
   -snucleotide1       boolean    Sequence is nucleotide
   -sprotein1          boolean    Sequence is protein
   -slower1            boolean    Make lower case
   -supper1            boolean    Make upper case
   -scircular1         boolean    Sequence is circular
   -squick1            boolean    Read id and sequence only
   -sformat1           string     Input sequence format
   -iquery1            string     Input query fields or ID list
   -ioffset1           integer    Input start position offset
   -sdbname1           string     Database name
   -sid1               string     Entryname
   -ufo1               string     UFO features
   -fformat1           string     Features format
   -fopenfile1         string     Features file name

   "-graph" associated qualifiers
   -gprompt            boolean    Graph prompting
   -gdesc              string     Graph description
   -gtitle             string     Graph title
   -gsubtitle          string     Graph subtitle
   -gxtitle            string     Graph x axis title
   -gytitle            string     Graph y axis title
   -goutfile           string     Output file for non interactive displays
   -gdirectory         string     Output directory

   General qualifiers:
   -auto               boolean    Turn off prompts
   -stdout             boolean    Write first file to standard output
   -filter             boolean    Read first file from standard input, write
                                  first file to standard output
   -options            boolean    Prompt for standard and additional values
   -debug              boolean    Write debug output to program.dbg
   -verbose            boolean    Report some/full command line options
   -help               boolean    Report command line options and exit. More
                                  information on associated and general
                                  qualifiers can be found with -help -verbose
   -warning            boolean    Report warnings
   -error              boolean    Report errors
   -fatal              boolean    Report fatal errors
   -die                boolean    Report dying program messages
   -version            boolean    Report version number and exit

Qualifier Type Description Allowed values Default
Standard (Mandatory) qualifiers
[-sequence]
(Parameter 1)		 sequence Nucleotide sequence filename and optional format, or reference (input USA) Readable sequence Required
-graph graph Graph type EMBOSS has a list of known devices, including ps, hpgl, hp7470, hp7580, meta, cps, x11, tek, tekt, none, data, xterm, png, gif, pdf, svg EMBOSS_GRAPHICS value, or x11
Additional (Optional) qualifiers
(none)
Advanced (Unprompted) qualifiers
(none)
Associated qualifiers
"-sequence" associated sequence qualifiers
-sbegin1
-sbegin_sequence		 integer Start of the sequence to be used Any integer value 0
-send1
-send_sequence		 integer End of the sequence to be used Any integer value 0
-sreverse1
-sreverse_sequence		 boolean Reverse (if DNA) Boolean value Yes/No N
-sask1
-sask_sequence		 boolean Ask for begin/end/reverse Boolean value Yes/No N
-snucleotide1
-snucleotide_sequence		 boolean Sequence is nucleotide Boolean value Yes/No N
-sprotein1
-sprotein_sequence		 boolean Sequence is protein Boolean value Yes/No N
-slower1
-slower_sequence		 boolean Make lower case Boolean value Yes/No N
-supper1
-supper_sequence		 boolean Make upper case Boolean value Yes/No N
-scircular1
-scircular_sequence		 boolean Sequence is circular Boolean value Yes/No N
-squick1
-squick_sequence		 boolean Read id and sequence only Boolean value Yes/No N
-sformat1
-sformat_sequence		 string Input sequence format Any string  
-iquery1
-iquery_sequence		 string Input query fields or ID list Any string  
-ioffset1
-ioffset_sequence		 integer Input start position offset Any integer value 0
-sdbname1
-sdbname_sequence		 string Database name Any string  
-sid1
-sid_sequence		 string Entryname Any string  
-ufo1
-ufo_sequence		 string UFO features Any string  
-fformat1
-fformat_sequence		 string Features format Any string  
-fopenfile1
-fopenfile_sequence		 string Features file name Any string  
"-graph" associated graph qualifiers
-gprompt boolean Graph prompting Boolean value Yes/No N
-gdesc string Graph description Any string Chaos game representation
-gtitle string Graph title Any string  
-gsubtitle string Graph subtitle Any string  
-gxtitle string Graph x axis title Any string  
-gytitle string Graph y axis title Any string  
-goutfile string Output file for non interactive displays Any string  
-gdirectory string Output directory Any string  
General qualifiers
-auto boolean Turn off prompts Boolean value Yes/No N
-stdout boolean Write first file to standard output Boolean value Yes/No N
-filter boolean Read first file from standard input, write first file to standard output Boolean value Yes/No N
-options boolean Prompt for standard and additional values Boolean value Yes/No N
-debug boolean Write debug output to program.dbg Boolean value Yes/No N
-verbose boolean Report some/full command line options Boolean value Yes/No Y
-help boolean Report command line options and exit. More information on associated and general qualifiers can be found with -help -verbose Boolean value Yes/No N
-warning boolean Report warnings Boolean value Yes/No Y
-error boolean Report errors Boolean value Yes/No Y
-fatal boolean Report fatal errors Boolean value Yes/No Y
-die boolean Report dying program messages Boolean value Yes/No Y
-version boolean Report version number and exit Boolean value Yes/No N

Input file format

chaos reads a single nucleotide sequence.

The input is a standard EMBOSS sequence query (also known as a 'USA').

Major sequence database sources defined as standard in EMBOSS installations include srs:embl, srs:uniprot and ensembl

Data can also be read from sequence output in any supported format written by an EMBOSS or third-party application.

The input format can be specified by using the command-line qualifier -sformat xxx, where 'xxx' is replaced by the name of the required format. The available format names are: gff (gff3), gff2, embl (em), genbank (gb, refseq), ddbj, refseqp, pir (nbrf), swissprot (swiss, sw), dasgff and debug.

See: http://emboss.sf.net/docs/themes/SequenceFormats.html for further information on sequence formats.

Input files for usage example

'tembl:j01636' is a sequence entry in the example nucleic acid database 'tembl'

Database entry: tembl:j01636

ID   J01636; SV 1; linear; genomic DNA; STD; PRO; 7477 BP.
XX
AC   J01636; J01637; K01483; K01793;
XX
DT   30-NOV-1990 (Rel. 26, Created)
DT   09-SEP-2004 (Rel. 81, Last updated, Version 8)
XX
DE   E.coli lactose operon with lacI, lacZ, lacY and lacA genes.
XX
KW   acetyltransferase; beta-D-galactosidase; galactosidase; lac operon;
KW   lac repressor protein; lacA gene; lacI gene; lactose permease; lacY gene;
KW   lacZ gene; mutagenesis; palindrome; promoter region;
KW   thiogalactoside acetyltransferase.
XX
OS   Escherichia coli
OC   Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacteriales;
OC   Enterobacteriaceae; Escherichia.
XX
RN   [1]
RP   1243-1266
RX   DOI; 10.1073/pnas.70.12.3581.
RX   PUBMED; 4587255.
RA   Gilbert W., Maxam A.;
RT   "The nucleotide sequence of the lac operator";
RL   Proc. Natl. Acad. Sci. U.S.A. 70(12):3581-3584(1973).
XX
RN   [2]
RP   1246-1308
RX   DOI; 10.1073/pnas.70.12.3585.
RX   PUBMED; 4587256.
RA   Maizels N.M.;
RT   "The nucleotide sequence of the lactose messenger ribonucleic acid
RT   transcribed from the UV5 promoter mutant of Escherichia coli";
RL   Proc. Natl. Acad. Sci. U.S.A. 70(12):3585-3589(1973).
XX
RN   [3]
RX   PUBMED; 4598642.
RA   Gilbert W., Maizels N., Maxam A.;
RT   "Sequences of controlling regions of the lactose operon";
RL   Cold Spring Harb. Symp. Quant. Biol. 38:845-855(1974).
XX
RN   [4]
RA   Gilbert W., Gralla J., Majors A.J., Maxam A.;
RT   "Lactose operator sequences and the action of lac repressor";
RL   (in) Sund H., Blauer G. (Eds.);
RL   PROTEIN-LIGAND INTERACTIONS:193-207;
RL   Walter de Gruyter, New York (1975)
XX
RN   [5]
RP   1146-1282


  [Part of this file has been deleted for brevity]

     cgatttggct acatgacatc aaccatatca gcaaaagtga tacgggtatt atttttgccg      4560
     ctatttctct gttctcgcta ttattccaac cgctgtttgg tctgctttct gacaaactcg      4620
     ggctgcgcaa atacctgctg tggattatta ccggcatgtt agtgatgttt gcgccgttct      4680
     ttatttttat cttcgggcca ctgttacaat acaacatttt agtaggatcg attgttggtg      4740
     gtatttatct aggcttttgt tttaacgccg gtgcgccagc agtagaggca tttattgaga      4800
     aagtcagccg tcgcagtaat ttcgaatttg gtcgcgcgcg gatgtttggc tgtgttggct      4860
     gggcgctgtg tgcctcgatt gtcggcatca tgttcaccat caataatcag tttgttttct      4920
     ggctgggctc tggctgtgca ctcatcctcg ccgttttact ctttttcgcc aaaacggatg      4980
     cgccctcttc tgccacggtt gccaatgcgg taggtgccaa ccattcggca tttagcctta      5040
     agctggcact ggaactgttc agacagccaa aactgtggtt tttgtcactg tatgttattg      5100
     gcgtttcctg cacctacgat gtttttgacc aacagtttgc taatttcttt acttcgttct      5160
     ttgctaccgg tgaacagggt acgcgggtat ttggctacgt aacgacaatg ggcgaattac      5220
     ttaacgcctc gattatgttc tttgcgccac tgatcattaa tcgcatcggt gggaaaaacg      5280
     ccctgctgct ggctggcact attatgtctg tacgtattat tggctcatcg ttcgccacct      5340
     cagcgctgga agtggttatt ctgaaaacgc tgcatatgtt tgaagtaccg ttcctgctgg      5400
     tgggctgctt taaatatatt accagccagt ttgaagtgcg tttttcagcg acgatttatc      5460
     tggtctgttt ctgcttcttt aagcaactgg cgatgatttt tatgtctgta ctggcgggca      5520
     atatgtatga aagcatcggt ttccagggcg cttatctggt gctgggtctg gtggcgctgg      5580
     gcttcacctt aatttccgtg ttcacgctta gcggccccgg cccgctttcc ctgctgcgtc      5640
     gtcaggtgaa tgaagtcgct taagcaatca atgtcggatg cggcgcgacg cttatccgac      5700
     caacatatca taacggagtg atcgcattga acatgccaat gaccgaaaga ataagagcag      5760
     gcaagctatt taccgatatg tgcgaaggct taccggaaaa aagacttcgt gggaaaacgt      5820
     taatgtatga gtttaatcac tcgcatccat cagaagttga aaaaagagaa agcctgatta      5880
     aagaaatgtt tgccacggta ggggaaaacg cctgggtaga accgcctgtc tatttctctt      5940
     acggttccaa catccatata ggccgcaatt tttatgcaaa tttcaattta accattgtcg      6000
     atgactacac ggtaacaatc ggtgataacg tactgattgc acccaacgtt actctttccg      6060
     ttacgggaca ccctgtacac catgaattga gaaaaaacgg cgagatgtac tcttttccga      6120
     taacgattgg caataacgtc tggatcggaa gtcatgtggt tattaatcca ggcgtcacca      6180
     tcggggataa ttctgttatt ggcgcgggta gtatcgtcac aaaagacatt ccaccaaacg      6240
     tcgtggcggc tggcgttcct tgtcgggtta ttcgcgaaat aaacgaccgg gataagcact      6300
     attatttcaa agattataaa gttgaatcgt cagtttaaat tataaaaatt gcctgatacg      6360
     ctgcgcttat caggcctaca agttcagcga tctacattag ccgcatccgg catgaacaaa      6420
     gcgcaggaac aagcgtcgca tcatgcctct ttgacccaca gctgcggaaa acgtactggt      6480
     gcaaaacgca gggttatgat catcagccca acgacgcaca gcgcatgaaa tgcccagtcc      6540
     atcaggtaat tgccgctgat actacgcagc acgccagaaa accacggggc aagcccggcg      6600
     atgataaaac cgattccctg cataaacgcc accagcttgc cagcaatagc cggttgcaca      6660
     gagtgatcga gcgccagcag caaacagagc ggaaacgcgc cgcccagacc taacccacac      6720
     accatcgccc acaataccgg caattgcatc ggcagccaga taaagccgca gaaccccacc      6780
     agttgtaaca ccagcgccag cattaacagt ttgcgccgat cctgatggcg agccatagca      6840
     ggcatcagca aagctcctgc ggcttgccca agcgtcatca atgccagtaa ggaaccgctg      6900
     tactgcgcgc tggcaccaat ctcaatatag aaagcgggta accaggcaat caggctggcg      6960
     taaccgccgt taatcagacc gaagtaaaca cccagcgtcc acgcgcgggg agtgaatacc      7020
     acgcgaaccg gagtggttgt tgtcttgtgg gaagaggcga cctcgcgggc gctttgccac      7080
     caccaggcaa agagcgcaac aacggcaggc agcgccacca ggcgagtgtt tgataccagg      7140
     tttcgctatg ttgaactaac cagggcgtta tggcggcacc aagcccaccg ccgcccatca      7200
     gagccgcgga ccacagcccc atcaccagtg gcgtgcgctg ctgaaaccgc cgtttaatca      7260
     ccgaagcatc accgcctgaa tgatgccgat ccccacccca ccaagcagtg cgctgctaag      7320
     cagcagcgca ctttgcgggt aaagctcacg catcaatgca ccgacggcaa tcagcaacag      7380
     actgatggcg acactgcgac gttcgctgac atgctgatga agccagcttc cggccagcgc      7440
     cagcccgccc atggtaacca ccggcagagc ggtcgac                               7477
//

Output file format

The output is to the specified graphics device.

The results can be output in one of several formats by using the command-line qualifier -graph xxx, where 'xxx' is replaced by the name of the required device. Support depends on the availability of third-party software packages.

The device names that output to a file are: ps (postscript), cps (colourps), png, gif, pdf, svg, hpgl, hp7470, hp7580, das, data.

The other available device names are: meta, x11 (xwindows), tek (tek4107t), tekt (tektronix), xterm, text.

Output can be turned off by specifying none (null).

See: http://emboss.sf.net/docs/themes/GraphicsDevices.html for further information on supported devices.

Output files for usage example

Graphics File: chaos.ps

[chaos results]

Data files

None.

Notes

Regions which are devoid of dots (or heavily covered with dots) indicate short sequence motifs that are unusually infrequent (or frequent). The sequence of such motifs can be deduced by looking to see which quarter of the square the region is in - the letter that this quarter belongs to is the first base of the motif. The quarter is then quartered again and the appropriate base letters are assigned to the corners of the quarter - the part that the region is in gives the second base of the motif.

The process continues until you have identified the 1/16th or 1/32nd, etc. of the original square containing the unusual region and you now have the sequence of the motif.

References

  1. Jeffrey (1990) Nucleic Acids Research 18: 2163-2170 "Chaos game representation of gene structure"

Warnings

None.

Diagnostic Error Messages

None.

Exit status

0 upon successful completion.

Known bugs

None.

See also

Program name Description
banana Plot bending and curvature data for B-DNA
btwisted Calculate the twisting in a B-DNA sequence
compseq Calculate the composition of unique words in sequences
dan Calculate nucleic acid melting temperature
density Draw a nucleic acid density plot
freak Generate residue/base frequency table or plot
isochore Plot isochores in DNA sequences
wordcount Count and extract unique words in molecular sequence(s)

Author(s)

Ian Longden formerly at:
Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.

Please report all bugs to the EMBOSS bug team (emboss-bug © emboss.open-bio.org) not to the original author.

History

Completed 22nd March 1999.

Target users

This program is intended to be used by everyone and everything, from naive users to embedded scripts.

Comments

None