Ankyrin-B is required for coordinated expression of beta-2-spectrin, the Na/K-ATPase and the Na/Ca exchanger in the inner segment of rod photoreceptors.
Journal Article (Journal Article)
Rod photoreceptors are highly polarized cells whose exquisite sensitivity to light depends on precise compartmentalization of ion channels/transporters within specialized membrane domains. Here, we report evidence for an ankyrin-B based mechanism for coordinated expression of the beta-2-spectrin-based membrane skeleton, and the Na/K-ATPase and Na/Ca exchanger in the inner segment of rod photoreceptors. We first discovered that ankyrin-B localizes to the inner segments but not outer segments of rod photoreceptors in vertebrates including humans, mice, and frogs. We found that haploinsufficiency of ankyrin-B in mice is accompanied by 50% reduction in inner segments of membrane proteins, including the Na/K-ATPase and the Na/Ca exchanger, as well as beta-2-spectrin, which is a component of the spectrin-actin membrane skeleton. These results are consistent with a mechanism where ankyrin-B is required to restrict the Na/K-ATPase and Na/Ca exchanger to the inner segment of rod photoreceptors by tethering these membrane proteins to beta-2-spectrin.
Full Text
Duke Authors
Cited Authors
- Kizhatil, K; Sandhu, NK; Peachey, NS; Bennett, V
Published Date
- January 2009
Published In
Volume / Issue
- 88 / 1
Start / End Page
- 57 - 64
PubMed ID
- 19007774
Electronic International Standard Serial Number (EISSN)
- 1096-0007
Digital Object Identifier (DOI)
- 10.1016/j.exer.2008.09.022
Language
- eng
Conference Location
- England