Localization of Phosphoinositide Specific Phospholipase Cbeta Isozymes in Rat Cochlea.
- Author:
Chan PARK
1
;
Seung Hoon HAN
;
Han Kyu SUH
;
Hak Hyun JUNG
;
Soon Jae HWANG
;
Keun JUNG
;
Hyun Ho LIM
Author Information
1. Department of Otolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul, Korea. hyunho@kumc.or.kr
- Publication Type:Original Article
- Keywords:
Phospholipase C beta;
Cochlea
- MeSH:
Animals;
Antibodies;
Blotting, Western;
Cochlea*;
Collodion;
Ear, Inner;
Frozen Sections;
Gels;
Hair;
Hydrolysis;
Inositol 1,4,5-Trisphosphate;
Isoenzymes*;
Ligands;
Membranes;
Molecular Weight;
Phospholipase C beta;
Phospholipases*;
Rats*;
Receptors, Cell Surface;
Second Messenger Systems;
Signal Transduction;
Spiral Ganglion;
Stria Vascularis;
Type C Phospholipases
- From:Korean Journal of Otolaryngology - Head and Neck Surgery
1999;42(2):145-151
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND AND OBJECTIVES: Phosphoinositide specific phospholipase C (PLC) plays a pivotal role in the transmembrane signal transduction pathways by catalyzing the hydrolysis of phosphoinositide 4,5-bisphosphate (PIP2) to yield the intracellular second messengers, diacylglycerol (DG) and inositol 1,4,5-trisphosphate (IP3), in response to the interaction of various ligands with the cell surface receptors. The question arises as to the physiological roles of the phosphoinositide second messenger system in the inner ear. The purpose of this study was to determine whether PLCbeta isozymes are present at the cochlea and what portion of cochlea each PLCbeta isozymes are distributed in. MAERIALS AND METHODS: Two methods, an immunohistochemical staining and western blot for PLCbeta isozymes were used in the rat cochlea. Frozen section and surface preparation were prepared for immunohistochemical staining. The PLCbeta isozymes or proteolytic digests were separated by SDS-polyacrylamide gels and then electrophoretically transferred to nitrocellulose membranes. Rabbit polyclonal antibodies raised against four PLCbeta isozymes were used. RESULTS: Each PLCbeta isozymes showed differential expressions in the cochlea. PLCbeta1 immunoreactivity was observed in the inner and outer hair cells and the spiral ganglion cells; PLCbeta2 in the stria vascularis and PLCbeta3 mainly in the inner hair cells. PLCbeta4 was not observed in cochlea. In western blots of rat cochlea extracts, the PLCbeta isozymes stained several bands corresponding to the known molecular weight of PLCbeta monomers, which are probably proteolytic digests. CONCLUSION: These results suggest that differentially localized each PLCbeta isozymes in the cochlea may have specific roles in signal transduction pathway of auditory system.
