#mitotic spindle

[bpod-bpod]

Early Errors

Errors in cell division to which embryos are susceptible at the earliest stages of development can occur through abnormality in the shape of the mitotic spindle – the cell's inner scaffold that pulls the cell into two daughter cells during division

Read the published research article here

Still from a video from work by Yuki Ono and colleagues

Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita, Japan

Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in Nature Communications, June 2024

You can also follow BPoD on Instagram, Twitter and Facebook

[bpod-bpod]

Orienting Division

The molecular mechanisms underlying how the spindle – the cell apparatus that aligns the chromosomes during cell division – is oriented, pulling the division into two daughter cells

Read the published research article here

Image from work by Kathryn E Neville and Tara M Finegan, and colleagues

Department of Biology, University of Rochester, Rochester, New York, USA

Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in EMBO Reports, January 2023

You can also follow BPoD on Instagram, Twitter and Facebook

[adorable-amygdala]

Dividing Chromosomes Dr David Becker Winner of the Wellcome Image Awards 1998 “A confocal micrograph showing the process of cell division (mitosis) in which the chromosomes (red), containing all the genetic information, duplicate themselves to form two identical sets and then align themselves in the centre of the nucleus. One half of each pair is then pulled to opposite sides by a network of fibres called the mitotic spindle (green).”

[micromultiverse]

Phys.org: Team probes physical forces involved in creating the mitotic spindle.

[artandsciencejournal]

Creatures of chaos

It's revision week once again, and while studying my cell bio notes I keep getting distracted by microscopy pictures. The cytoskeleton chapter especially is a personal favorite of mine. I'm constantly amazed by these tiny little cells that build us. Text books with their pretty pictures, or me even with this picture of sand dollar zygotes taken during mitosis, don't do them justice. Cells are always changing shape, producing vesicles, dividing, migrating, secreting, and they wouldn't be doing so without their fibrous skeleton which allows them to organize, stretch and move. This wonderful network itself seems fixed, but it's polymerizing and depolymerizing at all times. We are all complex creatures, able to live because we are made of chaos.

Picture credit : George von Dassow / Learn more about it

Agathe of Frontal Cortex

[frontal-cortex]

Video 8. Single and double centrosome ablations in a sand dollar embryo coexpressing ensconsin-3xGFP (cyan) and mC-H2B (yellow). Time-lapse sequence of single confocal sections (Atto CARV). Video corresponds to Fig. S5 B. Real times are indicated, and the video is encoded at 15 frames/s. Bar, 25 µm.

George von Dassow et al; Action at a distance during cytokinesis, Journal of Cell Biology, December 14, 2009, vol. 187 no. 6 831-845 

Animal cells decide where to build the cytokinetic apparatus by sensing the position of the mitotic spindle. Reflecting a long-standing presumption that a furrow-inducing stimulus travels from spindle to cortex via microtubules, debate continues about which microtubules, and in what geometry, are essential for accurate cytokinesis. 

In normal cells, the cytokinetic apparatus forms in a region of lower cortical microtubule density. Ablation of a single centrosome displaces furrows away from the remaining centrosome; ablation of both centrosomes causes broad, inefficient furrowing. 

[frontal-cortex]

The mitotic spindle in a sand dollar embryo

The mitotic spindle (orange) segregates DNA (blue) in the dividing cells of a sand dollar embryo. von Dassow et al. demonstrate that spindle microtubules don’t need to touch the cell cortex for the cleavage furrow to assemble in the right place. (JCB 187(6) TOC1)

This image is available to the public to copy, distribute, or display under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported license. Published on: December 14, 2009. Doi: 10.1083/jcb.200907090

Read the full article at: jcb.rupress.org/cgi/content/full/187/6/831