**6. Lipids remodelling: Implications of lipid rafts (DRMs) in human malaria**

Despite identifying the roles and biogenesis of specific extracellular compartments of the parasite and the discovery of the protein exporting PEXEL motif with different models of trafficking pathways proposed, the contribution of lipids in these cellular processes is poorly understood even though the exported proteins have to bypass several membrane barriers to reach their final destination. Upon merozoite invasion, there is a change in the lipid and protein compositions of the infected erythrocyte membrane indicating that the parasite also remodels micro-domains of its host cell membrane known as lipid rafts and a lipid raft-based biogenesis of the parasitophorous vacuole membrane has been proposed. In addition, lipid raft-based processes and interactions of both host and parasite origin might be crucial to maintain the stability of the vacuolar environment for the parasite growth and pathogenesis [reviewed in (Murphy *et al*., 2006)].

Lipid rafts also serve as a stage for protein assemblies, sorting and trafficking through endocytic and secretory pathways in other cell types [reviewed in (Hanzal-Bayer & Hancock, 2007)]. Do DRMs have any contributions to *P. falciparum* protein trafficking pathways in infected erythrocytes? Tamez and colleagues have described a vesicle-like membrane compartment in the infected erythrocyte cytosol, which might be implicated in the import of lipids from the erythrocyte membrane to the TVN (Tamez *et al.*, 2008). Moreover, the binding of the parasite Hsp40 co-chaperone to "J-dots", proposed to be involved in protein trafficking through the erythrocyte cytosol, was shown to be cholesterol dependent (Külzer *et al.*, 2010). Furthermore, the presentation of the parasite virulence protein PfEMP1 on the erythrocyte surface involves the final insertion of the protein into cholesterol-rich domains of the erythrocyte plasma membrane (Frankland *et al.*, 2006) and with more delivery in the presence of serum lipoproteins (Frankland *et al.*, 2007). Whether all parasite proteins exported to the host cell surface are delivered to lipid rafts needs to be further investigated.

In conclusion, elucidating and characterizing the functional roles of cholesterol rich DRMs during the intra-erythrocytic development of the *P. falciparum* parasite might shed new light on protein trafficking or host cell remodelling processes.
