Latest News And Breaking Headlines

Understanding how motor proteins shape our cells

Nature Communications (2022). DOI: 10.1038/s41467-022-31794-3″ width=”685″ height=”530″/>

Structures of microtubule-unbound, microtubule-bound and bent tubulin-bound CaKip3. a) Top—Cartoon representation of catalytic intermediates of CaKip3’s motility and microtubule depolymerization cycles. Bottom view of a CaKip3-decorated microtubule (MT-CaKip3-MDC-ANP) cryo-EM map and the full CaKip3-decorated dolastatin-tubulin ring cryo-EM map. b) X-ray crystallographic density of CaKip3-MDN in the ADP state. ce) Cryo-EM maps of microtubule-bound CaKip3-MDC in the APO, AMP-PNP and ADP-AlFx nucleotide states. f) Cryo-EM maps of bent tubulin-bound CaKip3-MDC in the AMP-PNP state. Map surfaces are colored regionally according to the segment of the mounted protein model they enclose: -tubulin (cornflower blue), -tubulin (sky blue), kinesin motor core (orange), Switch I loop (forest green), Loop-11 of Switch II (magenta), neck-linker (red), nucleotide (tomato), loop-1 (yellow), loop-2 (lime green), helix-0 (dark blue). The figure was created with UCSF ChimeraX. Credit: Byron Hunter et al, nature communication (2022). DOI: 10.1038/s41467-022-31794-3

Understanding the busy networks in our cells could help researchers develop new cancer treatments and prevent dangerous fungal infections.

With help from the Canadian Light Source (CLS) at the University of Saskatchewan, a research team led by John Allingham of Queen’s University and Hernando Sosa of the Albert Einstein College of Medicine has shed light on a protein that regulates the intricate microscopic networks that give cells shape and help ship important molecules to different locations.

Using the CMCF beamline at the CLS and the cryo-EM facility at the Simons Electron Microscopy Center (SEMC) at the New York Structural Biology Center, the team found the missing pieces of an important puzzle.

In their published work, they are the first group to clearly describe the mechanism of action of a small motor protein called Kinesin-8, which enables it to control the structures of microtubule fiber networks in the cell.

“Our recent paper in nature communicationco-first author of Byron Hunter and Matthieu Benoit, shows how this particular type of kinesin motor protein evolved the ability to use microtubules as tracks for movement, directing the transport of cargo within the cell,” said Dr. John Allingham. , a professor at the Queen’s School of Medicine, “in addition to the ability to disassemble these spores, control their length and location in cells.”

The Kinesin-8 proteins ensure that a cell’s charge is in the right place during cell division and help regulate cellular networks so that the microtubules do not grow too long.

This research provides an important strategy for cancer treatment. The team is hopeful that targeting the Kinesin-8 proteins in cancer cells could contribute to anticancer treatments.

This strategy could also be used to develop a therapy for pathogenic fungal infections that threaten people with compromised immune systems.

Allingham said the CLS provides an invaluable training environment for its students, including Ph.D. candidate Byron Hunter who collected the CLS data for their recent work.

“The CLS platform was immensely valuable,” Hunter says. “The increase in the quality of the data was enormous. We were able to screen a huge number of different crystal samples in a relatively short time.”

First evidence of mechanosensitive behavior of microtubules

More information:
Byron Hunter et al, Kinesin-8-specific loop-2 regulates the motor domain dual activities according to the shape of the tubulin protofilament, nature communication (2022). DOI: 10.1038/s41467-022-31794-3

Quote: Understanding How Motor Proteins Make Our Cells (2022, Aug 9,), retrieved Aug 9, 2022 from https://phys.org/news/2022-08-motor-proteins-cells.html

This document is copyrighted. Other than fair dealing for personal study or research, nothing may be reproduced without written permission. The content is provided for informational purposes only.

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More