Abstract

OBJECTIVE:

To reveal the transcription profile of PfRON4 gene in Plasmodium falciparum erythrocytic stage.

METHODS:

P. falciparum schizonts were purified by differential centrifugation on a Percoll-sorbitol gradient, after which the released merozoites were allowed to invade uninfected erythrocytes for 4 hours before the clearance of all remaining schizonts using 5% D-sorbitol. The cultured synchronous parasites were harvested for RNA assay immediately, 24 hours later, and then at every 6th hour. PfRON4 and related genes (PfAMA1 and PfRhopH2) were amplified by real-time PCR for establishing standard curves to evaluate the copy number of genes.

RESULTS:

P. falciparum parasites were well synchronized. Those quantative analyses were reliable because the R value of standard curves were more than 0.98 and the melting curve showed a single peak. When parasites were in the schizont stage, PfRON4 gene transcription reached a peak in 36-40 hours after invasion.

CONCLUSION:

The transcription of PfRON4 peaks at mature schizont stage, suggesting that the PfRON4 gene may involve in erythrocyte-invasion of P. falciparum.