BBS proteins shown to run an export business that protects cilia

December 28, 2009

A protein complex mutated in human disease removes excess signaling molecules to prevent them from damaging cilia, say researchers from UMass Medical School. The study will be published in the December 28 issue of the Journal of Cell Biology (www.jcb.org).

Defective cilia cause a range of diseases including Bardet-Biedl syndrome (BBS), a rare, multi-tissue disorder linked to mutations in 12 different proteins. Seven of these form a complex called the BBSome, but the function of this protein assembly in cilia and flagella is unclear. In worms, the complex glues together the intraflagellar transport (IFT) machinery that assembles and maintains cilia by hauling cargo back and forth along the organelle's microtubules. But most mammalian cell types can still form cilia in the absence of BBS proteins, suggesting that the BBSome isn't essential for IFT.

Lechtreck et al. turned to the green alga Chlamydomonas, and found that BBS proteins were only present on a subset of IFT particles in each of the alga's two flagella. Strains lacking components of the BBSome showed normal rates of IFT and proper flagellar structure, but couldn't steer away from bright light like wild-type cells could. Mutant flagella accumulated several signaling-related proteins, which the researchers think may disrupt the alga's response to light.

The researchers speculate that a similar buildup of disruptive proteins causes cilia dysfunction in BBS patients; the BBSome may remove excess signaling proteins from flagella by linking them to a subset of IFT particles undergoing retrograde transport out of the cilia. Author Karl Lechtreck says that the next step is to fluorescently tag the signaling proteins and compare their movements to BBS and IFT proteins.
-end-
About the Journal of Cell Biology

Founded in 1955, the Journal of Cell Biology (JCB) is published by the Rockefeller University Press. All editorial decisions on manuscripts submitted are made by active scientists in conjunction with our in-house scientific editors. JCB content is posted to PubMed Central, where it is available to the public for free six months after publication. Authors retain copyright of their published works and third parties may reuse the content for non-commercial purposes under a creative commons license. For more information, please visit www.jcb.org.

Lechtreck, K.-F., et al. 2009. J. Cell Biol. doi:10.1083/jcb.200909183.

Rockefeller University Press

Related Proteins Articles from Brightsurf:

New understanding of how proteins operate
A ground-breaking discovery by Centenary Institute scientists has provided new understanding as to the nature of proteins and how they exist and operate in the human body.

Finding a handle to bag the right proteins
A method that lights up tags attached to selected proteins can help to purify the proteins from a mixed protein pool.

Designing vaccines from artificial proteins
EPFL scientists have developed a new computational approach to create artificial proteins, which showed promising results in vivo as functional vaccines.

New method to monitor Alzheimer's proteins
IBS-CINAP research team has reported a new method to identify the aggregation state of amyloid beta (Aβ) proteins in solution.

Composing new proteins with artificial intelligence
Scientists have long studied how to improve proteins or design new ones.

Hero proteins are here to save other proteins
Researchers at the University of Tokyo have discovered a new group of proteins, remarkable for their unusual shape and abilities to protect against protein clumps associated with neurodegenerative diseases in lab experiments.

Designer proteins
David Baker, Professor of Biochemistry at the University of Washington to speak at the AAAS 2020 session, 'Synthetic Biology: Digital Design of Living Systems.' Prof.

Gone fishin' -- for proteins
Casting lines into human cells to snag proteins, a team of Montreal researchers has solved a 20-year-old mystery of cell biology.

Coupled proteins
Researchers from Heidelberg University and Sendai University in Japan used new biotechnological methods to study how human cells react to and further process external signals.

Understanding the power of honey through its proteins
Honey is a culinary staple that can be found in kitchens around the world.

Read More: Proteins News and Proteins Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.