Direct evidence that the photoresponse of the Hermissenda type B photoreceptor cell is triggered directly by the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) was obtained. Neomycin and spermine, which inhibit PIP2 breakdown, suppressed light response, while injection of inositol 1,4,5-trisphosphate (IP3), guanosine 5′-(3-O-thio)triphosphate (GTPγS), guanosine 5′-(2-O-thio)diphosphate (GDPβS), cAMP, cGMP did not alter the light-induced Na+ influx underlying the photoresponse. Suppression of the photoresponse was also observed with decrease of total amount of membraneous PIP2 induced by injection of the phosphoinositides (PI) turnover inhibitors, isobutylmethylxanthine (IBMX), LiCl and R 59022.
|Number of pages||8|
|Journal||Biochemical and Biophysical Research Communications|
|Publication status||Published - 1994 Jul 15|
ASJC Scopus subject areas
- Molecular Biology