CLONING AND STRUCTURAL-ANALYSIS OF THE GENE ENCODING THE RIBOSOMAL-PROTEIN S6 FROM THE PARASITE LEISHMANIA-INFANTUM

We have cloned the S6 ribosomal protein encoding gene from a Leishmani a infantum cDNA library. This parasite protozoon, responsible for leis hmaniasis in Europe, is able to undergo developmental changes in vitro and results a good model to study cell differentiation processes. The LiS6 protein sequence indicates its pertinence to the SE protein fami ly, related to the early mechanisms of cell division, differentiation and activation, and shows an intermediate position between the yeasts and higher eukaryotes. Thus, LiS6 protein has the same amino acid leng th as that of the higher eukaryotes and certain common features such n ucleus entrance sequences and several kinase phosphorylation sites. Ho wever, the key functional protein kinase C phosphorylation sites are a t different locations and present several threonine instead of the usu al serine residues. The gene structural analysis suggest the presence of three different encoding genes that do not present remarkable chang es along the different phases of the parasite. (C) 1998 Academic Press .