Leishmania: overexpression and comparative structural analysis of the stage-regulated meta 1 gene

The meta 1 gene of Leishmania major is upregulated in metacyclic promastigotes and encodes an 11.5-kDa protein with no significant similarities to other proteins in the existing databases. In this paper, we characterize the homologous meta 1 genes in L. amazonensis and L. donovani. Proteins encoded by this gene in all three species present a high degree of identity. The meta 1 gene cannot be replaced by gene targeting in L. major, suggesting an essential role for the protein, at least in promastigotes. Overexpression of the meta 1 protein in L. amazonensis generates parasites that are more virulent than wild-type organisms in vivo.