toms@fcs260c2.ncifcrf.gov (Tom Schneider) (12/06/90)
A set of programs for analysis of aligned sequences is now available by anonymous ftp (file transfer protocol) at ncifcrf.gov in the directory 'pub/delila'. Further information is in a 'README' file, and the available files are listed in 'README.logo.Z', 'README.delila.Z' and 'README.misc.Z'. All files are comressed, except 'README'. The files are also available to people on BITNET from Dan Davison (davison@uh.edu) on "gene-server%bchs.uh.edu@CUNYVM" (many thanks to Dan for this service). The programs are part of the Delila System [1,2], and contain the Sequence Logo programs recently described in [2]. The abstract for [3], describing Sequence Logos is: A graphical method is presented for displaying the patterns in a set of aligned sequences. The characters representing the sequence are stacked on top of each other for each position in the aligned sequences. The height of each letter is made proportional to its frequency, and the letters are sorted so the most common one is on top. The height of the entire stack is then adjusted to signify the information content of the sequences at that position. From these `sequence logos', one can determine not only the consensus sequence but also the relative frequency of bases and the information content (measured in bits) at every position in a site or sequence. The logo displays both significant residues and subtle sequence patterns. Have fun! If you have any problems, please contact me. Tom Schneider National Cancer Institute Laboratory of Mathematical Biology Frederick, Maryland 21702-1201 toms@ncifcrf.gov References: [1] @article{Schneider1982, author = "T. D. Schneider and G. D. Stormo and J. S. Haemer and L. Gold", title = "A design for computer nucleic-acid sequence storage, retrieval and manipulation", journal = "Nucl. Acids Res.", volume = "10", pages = "3013-3024", year = "1982"} [2] @article{Schneider1984, author = "T. D. Schneider and G. D. Stormo and M. A. Yarus and L. Gold", title = "Delila system tools", year = "1984", journal = "Nucl. Acids Res.", volume = "12", pages = "129-140"} [3] @article{Schneider.Stephens.Logo, author = "T. D. Schneider and R. M. Stephens", title = "Sequence Logos: A New Way to Display Consensus Sequences", journal = "Nucl. Acids Res.", volume = "18", pages = "6097-6100", year = "1990"}