Sequence Analysis and Genotypes of Glutamate Rich Protein of Plasmodium falciparum Isolates from Different Malaria Endemic Areas in China

摘要

Objective To sequence the gene encoding glutamate rich protein (GLURP) andidentify the genotypes of geographically different Plasmodium falciparum (P. f ) isolatesfrom China. Methods The gene of R2 repeat region of GLURP was amplified by nestedpolymerase chain reaction and cloned into T-vector. The nucleotide sequence of GLURPgene was determined by automatic sequencer (Dideoxy termination method) and analyzed byDNA Star software. Results At least 7 different GLURP genotypes ranging from 600 bpto 1 500 bp were found in Yunnan and Hainan provinces. R2 region of GLURP gene consistedof several repeat units. Each repeat unit was composed of 19-20 residues which were shownto be highly conserved. GLURP gene was also size polymorphic due to differences in thenumber of repeat units, whereas the repeat sequence was conserved. Sequence analysisshowed that DNA sequences and deduced amino acid sequences were highly homologousamong the geographically dispersed isolates or various isolates from the same geographicalregion. No obvious differences were found in the GLURP gene sequences amonggeographically different isolates. Conclusion GLURP gene is highly structure conservedand size polymorphic, and so is useful in searching for malaria vaccine candidate antigen anddeveloping a genotyping method for malaria research.