First published online April 5, 2006
Journal of Cell Science 119, 804e (2006)
© The Company of Biologists Limited
Lysosomes on the move
Organelles have unique peripheral membrane proteins that mediate interactions with the cytoskeleton and transport of vesicles between organelles. These proteins are recruited by activated GTPases or phospholipids that are specific to each type of organelle. On p. 1494, Irmgard Hofmann and Sean Munro identify the first GTPases that localize to mammalian lysosomes: two closely related human Arf-like GTPases called Arl8a and Arl8b. The authors show that, unusually, acetylation of the N-terminal methionine residue of Arl8b is required for its binding to membranes – most Arf and Arl proteins bind to membranes through an N-terminal myristoyl group. They also report that overexpression of Arl8a or Arl8b leads to microtubule-dependent redistribution of lysosomes towards the cell periphery and stimulates lysosomal motility. Hofmann and Munro therefore propose that these Arls – and probably their orthologs in other organisms – might function in some of the dynamic processes that depend on lysosomes, such as phagocytosis.
Related articles in JCS:
- An N-terminally acetylated Arf-like GTPase is localised to lysosomes and affects their motility
- Irmgard Hofmann and Sean Munro
JCS 2006 119: 1494-1503.
[Abstract]
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