Sequence Analysis of Different Domains of Plasmodium vivax Apical Membrane Antigen (PvAMA-1 gene) Locus in Iran

Background: plasmodium vivax is responsible for approximately 80 million malaria cases in the world. apical membrane antigen1 (ama-1) is a type i integral membrane protein present in all plasmodium species. ama-1 interferes in critical steps of invasion of human hepatocytes by sporozoites and red blood cells by merozoites and is one of the most immunodominant antigens for elicit- ing a protective immune response in human. it is considered as a promising antigen for inclusion in a vaccine against p. vivax. since more knowledge is needed to lighten the scope of such antigen we compared genetic variation in p. vivax ama-1from an iranian isolate with those reported from some of the other malarious countries so far. methods: p. vivax genomic dna was extracted from the whole blood of an iranian patient with pa- tent p. vivax infection. the nucleotide sequence for 446 amino acid (aa) residues (42–488 of pvama-1) was amplified by pcr and cloned in puc19 vector for sequencing. results: sequence analysis of the antigen showed a high degree of identity (99%) with strong homol- ogy to the pvama-1 gene of p. vivax s3 and sko814 isolates from india and korea (asian isolates) respectively, and 96% similarity with p. vivax sal-1 ama-1 gene from el salvador. conclusions: we cloned and characterized three domains of pvama-1 gene from an iranian patient. predicted protein sequence of this gene showed some discrepancies in corresponding protein in comparing with similar genes reported from other malarious countries.