program: http://www.arabidopsis.org/wublast/index2.jsp to the amino acid sequence of TC117774 (MtN21) at: http://compbio. dfci.harvard.edu/tgi/cgi-bin/tgi/gireport.pl?gudb = medicago (B) Alignment of the Arabidopsis homologs of the M. truncatula MtN21 (TC114239) late nodulin gene. The alignment was done using ClustalW2 multiple sequence alignment website from the European Bioinformatics Institute (http://www.ebi.ac.uk/Tools/ clustalw2/index.html). Found at: doi:10.1371/journal.pone.0008399.s005 (0.09 MB PDF) Figure S6 Phylogenetic tree of the NPR1 protein. (A) Phylogenetic N-J tree of the M. truncatula genes that are homologous to the Arabidopsis NPR1. The tree was constructed using the Kyoto University ClustalW multiple sequence align- ment website, (http://align.genome.jp/). The right panel shows the unrooted version of the tree. Genes were selected using the BLAST program at http://compbio.dfci.harvard.edu/tgi/cgi- bin/tgi/gireport.pl?gudb = medicago. 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Molec Plant-Microbe Interact 15: 522–528. PLoS ONE | www.plosone.org 9 December 2009 | Volume 4 | Issue 12 | e8399