A 'guilt by association' test can correctly pinpoint the function of proteins, reports a team led by Elizabeth Winzeler of the Scripps Research Institute in La Jolla, California. An algorithm the researchers wrote found that the malaria-causing parasite Plasmodium falciparum expresses a gene encoding CDPK1 — a protein with an unknown role — at the same time as some other genes involved in cell invasion and movement. These all become active as the parasite prepares for its sexual stage.
The authors then screened a chemical library for compounds that block CDPK1. One of these inhibited the protein and also prevented P. falciparum from entering its sexual stage, indicating that the bioinformatics algorithm had provided accurate clues to CDPK1's role.