Project description:Heterochromatin is a tightly packaged form of DNA that leads to permanent or temporal gene silencing. In P. falciparum heterochromatin is formed after trimethylation of lysine 9 on histone H3 and consequent binding of heterochromatin protein 1 (HP1). Genome-wide profiling studies established that in P. falciparum blood stage schizonts heterochromatin is formed at subtelomeres and some intra-chromosomal islands. Reversible silencing of genes located in these regions has been shown to be key to, among others, antigenic variation, invasion pathway selection or commitment to gametocytogenesis. However, heterochromatic gene silencing has not been investigated in many other Plasmodium species, strains or life cycle stages, yet. Here, we used ChIP-seq to profile HP1 occupancy in asexual parasites of six different species (P. falciparum, P. knowlesi, P. vivax, P. berghei, P. yoelii, and P. chabaudi) and of four different P. falciparum strains (3D7, PF2004, NF54, NF135) as well as two different P. knowlesi clones (A1C1, A1H1). Additionally, we performed HP1 ChIP-seq on three asexual stages (ring, trophozoite and schizont stage) and two sexual stages of P. falciparum parasites. Collectively, the generated HP1 profiles provide a detailed catalog of heterochromatic genes and reveal conserved and specialized features of epigenetic control at different life cycle stages, strains and species across the genus Plasmodium.
Project description:High throughput sequencing was used to investigate the production of small RNAs from in Chlamydomonas in different strains and different stages of the life cycle. The association between these and methylation was assessed using genomic sequencing, comparing a sequenced genome with one enriched for methylated DNA sequence by immuno-precipitation.