Researchers screen 700 molecules by RNAi to identify host factors involved in malaria infection

The researchers of the Malaria Unit at Instituto de Medicina Molecular (IMM, Lisbon, Portugal) publish in the peer reviewed journal PLoS Pathogens the results of a large scale screening of more than 700 genes to identify host factors involved in the liver stage of malaria infection.

The study is based on the application of RNA interference technology (RNAi technology), which allows the repression of specific genes, and in the use of fluorescence microscopy to monitor the effect of the gene repression on the liver stage of malaria infection.

The study was developed by Miguel Prudêncio, Cristina Rodrigues and colleagues at the IMM Malaria Unit, directed by Maria Mota. Part of the study was conducted at the biotech company Cenyx (Dresden, Germany), a worldwide leader in RNAi technology.

The large scale screening focused on genes involved in signaling pathways (which allow cells to receive, and respond to, external stimuli), and led to the identification of at least 5 proteins whose inhibition causes reduction of malaria infection at the liver stage. The liver stage of malaria infection is the initial step of host invasion by the malaria parasite and is determinant to the replication of the parasite, preceding the appearance of the symptoms of the disease.

"The idea now is to unravel how these host proteins influence the malaria infection, to understand in which molecular mechanisms they participate", says Miguel Prudencio.  "The screening is, in itself, an important step in malaria research , but is also the beginning of further research", says Cristina D. Rodrigues. The characterization of the molecular mechanisms of infection in which the proteins now identified participate is presently one of the research lines of IMM Malaria Unit.

The present study highlights the competitiveness of the IMM Malaria Unit, which has been able to attract important international funding. "This study was possible only with the substantial funding of the European Science Foundation, which contributed substantially to the funding of our research team through the EURY programme", says Maria Mota. "This publication is the result of an enormous research and financial effort from our laboratory", continues Maria Mota.