Mitosis and cytokinesis in the binucleate intestinal parasite Giardia intestinalis must ensure that both daughters inherit one copy of each parental nucleus and a full set of the complex cytoskeletal structures required for parasite virulence. Previous work has suggested that mitosis in Giardia involves unconventional mechanisms for chromosome segregation. But, on p. 4889, Zacheus Cande and colleagues report that, although it does have several distinctive aspects, the major cytological events of Giardia mitosis (including chromosome segregation) resemble those in other organisms. The authors use 3D deconvolution light and transmission electron microscopy and conserved cytological markers to analyse mitosis and cytokinesis in Giardia. One distinctive aspect they reveal is a `semi-open' mitosis in which the two spindles are outside the nuclei and access the chromatin through openings in the nuclear membranes, which remain intact throughout mitosis. Overall, the authors propose that lateral chromosome segregation along the left-right axis and cytokinesis along the longitudinal plane (perpendicular to the spindles) ensure that Giardia progeny inherit one copy of each parental nucleus with mirror-image symmetry.
Double trouble in Giardia mitosis
Double trouble in Giardia mitosis. J Cell Sci 1 December 2006; 119 (23): e2304. doi:
Download citation file:
Advertisement
Cited by
Interviews with Biologists @ 100 conference speakers

Explore our interviews with keynote speakers from the Biologists @ 100 conference, hosted to celebrate our publisher’s 100th anniversary, where we discuss climate change and biodiversity with Hans-Otto Pörtner and Jane Francis, health and disease with Charles Swanton and emerging technologies with Manu Prakash and Jennifer Lippincott-Schwartz.
Introducing our new Associate Editors

In this Editorial, JCS Editor-in-Chief Michael Way welcomes five new Associate Editors to the JCS team. These Associate Editors will expand our support for the wider cell biology community and handle articles in immune cell biology, proteostasis, imaging and image analysis, plant cell biology, and stem cell biology and modelling.
The spatial choreography of mRNA biosynthesis

In their Review, André Ventura-Gomes and Maria Carmo-Fonseca detail the latest research progress and technological advancements that are helping to unlock how nuclear organisation underpins control of gene transcription and pre-mRNA splicing.
JCS-FocalPlane Training Grants

Early-career researchers - working in an area covered by JCS - who would like to attend a microscopy training course, please apply. Deadline dates for 2025 applications: 6 June 2025 (decision by week commencing 28 July 2025) and 5 September 2025 (decision by week commencing 20 October 2025).
The emerging roles of the endoplasmic reticulum in mechanosensing and mechanotransduction

In their Review, Jonathan Townson and Cinzia Progida highlight recently emerging evidence for a role of the endoplasmic reticulum in enabling a cell to sense and respond to changes in the extracellular mechanical environment.