TgChromo1 participates to the nuclear organisation of the nucleus.

<p>TgChromo1 participates in the functional organisation of the nucleus. The schematic represents the chromosomes in the nucleus with the centromere and telomere clusters occupied by TgChromo1 and their position at the periphery of the nucleus.</p

TgChromo1 expression is cell cycle regulated.

<p><b>A:</b> IFA of TgChromo1-HA (green) and IMC1 (red), a marker of the inner membrane complex, throughout the cell cycle. Parasites representative of interphase (G1) and mitosis are presented. Parasite nuclei are labelled with DAPI. <b>B:</b> Comparison of the intensity of the signal produced by IFA of TgChromo1-HA in interphase (G1) and during budding (Budding, B). IMC1, a marker of the inner membrane complex, is used to identify emerging daughter cells during the budding. Parasites during budding (B) are arrowed. Parasite nuclei are labelled with DAPI. <b>C:</b> TgChromo1 is concentrated in foci of different intensity. IFA was performed using an anti-HA antibody and the IMC1 antibody. Parasites nuclei are labelled with DAPI. Foci of lesser intensity are arrowed.</p

Subtelomeric repeats occupy the same nucleus territory as TgChromo1.

<p>FISH/IFA of TgChromo1-HA (green) and chromosome IX telomeric repeats (red). Parasite nuclei are labelled with DAPI (blue). Colocalising signals from FISH and IFA are arrowed.</p

TgChromo1 binds to peri-centromeric heterochromatin.

<p>ChIP on chip was performed with the TgChromo1 antibody (anti-CHD1, red) or the anti-HA antibody (HA, black) and hybridized on a genome-wide tiling microarray. The regions of enrichment for H3K9me3 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032671#pone.0032671-Brooks1" target="_blank">[12]</a> are represented in blue. A snapshot of the 12 chromosomes where a centromere was identified <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032671#pone.0032671-Brooks1" target="_blank">[12]</a> is presented. ChIP on chip signals are represented as a log2 ratio of the signal given by the immunoprecipitated DNA over the input and plotted according to the genomic position of the oligonucleotide.</p

Colocalisation of TgChromo1 and peri-centromeric sequences and identification of a missing centromere on chromosome IV.

<p><b>A:</b> Genomic localisation of the FISH probes. Fish probes (red rectangles) approximate locations are plotted against the signal of the TgChromo1-HA ChIP on chip. <b>B:</b> FISH/IFA of TgChromo1-HA (green) and chromosome IX peri-centromeric repeats (red). Parasite nuclei are labelled with DAPI (blue). <b>C:</b> FISH/IFA of TgChromo1-HA (green) and chromosome IV putative peri-centromeric repeats (red). Parasites nuclei are labelled with DAPI (blue). <b>D:</b> Quantification of the overlap coefficient between the signals of FISH and IFA. The coefficient is expressed as a ratio of the number of pixel overlapping in IFA over FISH in a given area.</p

TgChromo1 is maintained near the centrosome and the centrocone throughout the cell cycle.

<p><b>A:</b> IFA of TgChromo1-HA (green) and centrin1 (red), a marker of the centrosome. Parasite nuclei are labelled with DAPI (blue) at the interphase (G1), mitosis and the beginning of budding. <b>B:</b> IFA of TgChromo1-HA (green) and MORN1 (red), a marker of the centrocone. Parasite nuclei are labelled with DAPI (blue) at the interphase (G1), mitosis and the beginning of budding.</p