Abstract
Intracellular Ca2+ plays an important role in a variety of second messenger cascades. The function of Ca2+ is mediated, in part, by Ca2+-binding proteins such as calmodulin, calretinin, calbindin, neurocalcin, recoverin, and visinin-like proteins (VILIPs). These proteins are highly expressed in rat olfactory receptor neurons (ORNs) and are localized to distinct intracellular regions. In the present study, we have identified another Ca2+-binding protein, hippocalcin, in the rat olfactory epithelium (OE). Olfactory/brain hippocalcin shows high sequence homology with hippocalcins expressed in mice and humans. Hippocalcin was predominantly localized to the olfactory cilia, the site of the initial events of olfactory signal transduction, and was found to regulate the activity of ciliary adenylate cyclases (ACs) and particulate guanylyl cyclases (GCs) in a Ca 2+-dependent manner. These data indicate that hippocalcin is expressed in rat ORNs, and is likely to regulate second messenger cascades in a Ca2+-dependent manner.
| Original language | English |
|---|---|
| Pages (from-to) | 1131-1139 |
| Number of pages | 9 |
| Journal | Biochemical and Biophysical Research Communications |
| Volume | 322 |
| Issue number | 4 |
| DOIs | |
| State | Published - 1 Oct 2004 |
Bibliographical note
Funding Information:The authors wish to thank Drs. M. Kobayashi for his kind gift of hippocalcin antibody and Andrei Alekseev for pBB131 and his technical advice. The NINDS (GVR) and NIDCD (G.V.R., J.P.S., and C.M.) and Howard Hughes Medical Institute (A.M.) supported this work. This research was also supported by NIH Grant EY09339, a grant from Research to Prevent Blindness, Inc. (RPB) to the Departments of Ophthalmology at the University of Washington, and a grant from the E.K. Bishop Foundation. K.P. is the RPB Senior Investigator.