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Real-time dynamics of Plasmodium NDC80 reveals unusual modes of chromosome segregation during parasite proliferation.

ABSTRACT: Eukaryotic cell proliferation requires chromosome replication and precise segregation to ensure daughter cells have identical genomic copies. Species of the genus Plasmodium, the causative agents of malaria, display remarkable aspects of nuclear division throughout their life cycle to meet some peculiar and unique challenges to DNA replication and chromosome segregation. The parasite undergoes atypical endomitosis and endoreduplication with an intact nuclear membrane and intranuclear mitotic spindle. To understand these diverse modes of Plasmodium cell division, we have studied the behaviour and composition of the outer kinetochore NDC80 complex, a key part of the mitotic apparatus that attaches the centromere of chromosomes to microtubules of the mitotic spindle. Using NDC80-GFP live-cell imaging in Plasmodium berghei, we observe dynamic spatiotemporal changes during proliferation, including highly unusual kinetochore arrangements during sexual stages. We identify a very divergent candidate for the SPC24 subunit of the NDC80 complex, previously thought to be missing in Plasmodium, which completes a canonical, albeit unusual, NDC80 complex structure. Altogether, our studies reveal the kinetochore to be an ideal tool to investigate the non-canonical modes of chromosome segregation and cell division in Plasmodium.

SUBMITTER: Zeeshan M

PROVIDER: S-EPMC7340582 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Real-time dynamics of <i>Plasmodium</i> NDC80 reveals unusual modes of chromosome segregation during parasite proliferation.

Zeeshan Mohammad M Pandey Rajan R Pandey Rajan R Ferguson David J P DJP Tromer Eelco C EC Markus Robert R Abel Steven S Brady Declan D Daniel Emilie E Limenitakis Rebecca R Bottrill Andrew R AR Le Roch Karine G KG Holder Anthony A AA Waller Ross F RF Guttery David S DS Tewari Rita R

Journal of cell science 20200630 5

Eukaryotic cell proliferation requires chromosome replication and precise segregation to ensure daughter cells have identical genomic copies. Species of the genus <i>Plasmodium</i>, the causative agents of malaria, display remarkable aspects of nuclear division throughout their life cycle to meet some peculiar and unique challenges to DNA replication and chromosome segregation. The parasite undergoes atypical endomitosis and endoreduplication with an intact nuclear membrane and intranuclear mito ...[more]

PMID: 32501284

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Dataset Information

Real-time dynamics of Plasmodium NDC80 reveals unusual modes of chromosome segregation during parasite proliferation.

Publications

Real-time dynamics of <i>Plasmodium</i> NDC80 reveals unusual modes of chromosome segregation during parasite proliferation.

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