a moonlighting function of plasmodium falciparum histone 3, mono-methylated at lysine 9恶性疟原虫的兼职函数组蛋白3 mono-methylated赖氨酸9.pdfVIP

A Moonlighting Function of Plasmodium falciparum Histone 3, Mono-Methylated at Lysine 9? Yen-Hoon Luah, Balbir Kaur Chaal, Eugenia Ziying Ong, Zbynek Bozdech* School of Biological Sciences, Nanyang Technological University, Singapore, Singapore Abstract Background: In the human malaria parasites Plasmodium falciparum, histone modifications have been implicated in the transcriptional regulation. The acetylation and methylation status of the histones have been linked with transcriptional regulation of the parasite surface virulence factors as well as other genes with stage specific expression. In P. falciparum as well as other eukaryotes, different histone modifications were found to be compartmentalized to distinct regions in the nuclei. This compartmentalization is believed to be one of the main prerequisites for their function in epigenetic regulation of gene expression. Methodology/Principal Findings: Here we investigate intracellular distributions of five previously uncharacterized histone modifications including histone 4 acetylation on lysine residue 5 (H4K5Ac), H4K8Ac, H3K9Ac, H4Ac4 and H3K9Me1 during the asexual developmental stages. With the exception of H3K9Me1, the modified histones were localized to the nuclear periphery. This provides a strong indication that the P. falciparum nuclear periphery is one of the most active regions in epigenetic regulation of gene expression. Interestingly, H3K9Me1 is not associated with the nuclei but instead resides in the parasitophorous vacuole (PV), the double membrane compartments surrounding the parasite cell within the host erythrocyte. In this compartment, H3K9Me1 partially co-localizes with Etramp proteins. The localization of H3K9Me1 in the PV is conserved in the other species including P. yoelii and P. vivax. Conclusions: Similar to other eukaryotes,