Journal
NATURE CELL BIOLOGY
Volume 3, Issue 6, Pages 544-551Publisher
MACMILLAN PUBLISHERS LTD
DOI: 10.1038/35078517
Keywords
-
Categories
Funding
- NIGMS NIH HHS [GM 34225] Funding Source: Medline
Ask authors/readers for more resources
Regulation of actin dynamics at filament ends determines the organization and turnover of actin cytoskeletal structures. In striated muscle, it is believed that tight capping of the fast-growing (barbed) ends by Cap Z and of the slow-growing (pointed) ends by tropomodulin (Tmod) stabilizes the uniform lengths of actin (thin) filaments in myofibrils. Here we demonstrate for the first time that both Cap Z and Tmod are dynamic on the basis of the rapid incorporation of microinjected rhodamine-labelled actin (rho-actin) at both barbed and pointed ends and from the photobleaching of green fluorescent protein (GFP)-labelled Tmod, Unexpectedly, the inhibition of actin dynamics at pointed ends by GFP-Tmod overexpression results in shorter thin filaments, whereas the inhibition of actin dynamics at barbed ends by cytochalasin D has no effect on length. These data demonstrate that the actin filaments in myofibrils ave relatively dynamic despite the presence of capping proteins, and that regulated actin assembly at pointed ends determines the length of thin filaments.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available