Poster #RP122
Genes of the WD-repeat protein superfamily in the protozoan Leishmania: conservation and divergence in structure and function of flagellum-related sequences
Ana Luiza Bessa de Paula Barros*, Michel Toth Kamimura*, Ana Carolina Landim Pacheco*, Marcilia Pinheiro Costa*, Cleilton Lima Rocha*, Fabiana Freire Araújo*, Allan Rodrigo Soares Maia*, Wesley Jefferson Oliveira Alcoforado*, Jõao David Lira*, Hállison Lucas Ribeiro*, George de Paulo Ferreira*, Rodrigo Maggioni*, Raimundo Bezerra Costa*, Diana Magalhães Oliveira*
*Universidade Estadual do Ceará, Fortaleza, Brazil
The WD motif (also known as the Trp-Asp or WD40 motif) is found in a multitude of eukaryotic proteins involved in a variety of cellular processes. Where studied, repeated WD motifs act as a site for protein-protein interaction, and proteins containing WD repeats are known to serve as platforms for the assembly of protein complexes or mediators of transient interplay among other proteins. We have analyzed the predicted complement of WD proteins from Leishmania spp genomes, and compared them to those from other organisms. This analysis identified 795 potential Leishmania proteins containing four or more recognizable copies of the motif. These were classified into fewer distinct families, some of which contained more than one Leishmania member. Most of these families or individual proteins showed clear homology with WD proteins from the other eukaryotes analyzed. Where conservation was found, it often extended across all organisms, suggesting that many of these proteins are linked to basic cellular mechanisms, including flagellum-related mechanisms. Our results show that most Leishmania WD proteins are strongly conserved across eukaryotes, with diversity in function conferred at least in part by divergence in upstream signaling pathways, downstream regulatory targets and /or structure outside of the WD regions.