CONICET | Buscador de Institutos y Recursos Humanos

Aquaporins (AQP) constitute a well distributed and diversified protein family of channels whose structure remain highly conserved throughout species. These channels transport mainly water but some of them also transport solutes such as glycerol, hydrogen peroxide, etc. Trypanosoma cruzi (Tc) would have different AQP variants in its genome but there are only partial functional results for one of them. Thus, structural characterization of TcAQP is key to evaluate the physiological relevance of these channels on the parasite and to get progress in the knowledge of structure-function particularities of this protein family. In this work, AQP compatible sequences were searched for within Trytripdb database for all T cruzi strains. DNA was extracted from trypomastigotes (RA strain) cultured in Vero cell line. Each AQP sequence was elucidated after cloning in T7TS vector, bacteria transformation (E coli, DH5α), plasmid purification and sequencing (Macrogen). Multiple sequence alignments of AQPs was performed using all data base Tc strains and RA strain and a Phylogenetic analysis of all Kinetoplastid AQPs was also performed. 4 TcAQP were found (α to δ) for 13 Tc strains. Protein sizes are around 230 amino acids with the exception of β (450) and key amino acids and specific transport related motifs were compatible with water specific transport (Frogger?s positions, Ar/R, NPA1 and NPA2). 3D models were built by ab initio methods (Rosetta, iTasser) and pores were characterized based on molecular dynamics results (AMBER14SB and LIPID14 force field; Hole). Conserved AQP like tetrameric structures were shown by all constructed 3D models. This work is the first step in the full characterization of all TcAQP, further functional analysis of the transport of each TcAQP in vitro is still needed.