MOLECULAR-CLONING OF A PHOSPHOINOSITIDE-SPECIFIC PHOSPHOLIPASE-C FROMCATFISH OLFACTORY ROSETTES

A 2.7 kb clone encoding the partial (about 66%) sequence of a phosphoi nositide-specific phospholipase C (PLC) was isolated from a cDNA libra ry constructed from channel catfish (Ictalurus punctatus) olfactory ro settes. The clone, designated 30c7, was completely sequenced by automa ted DNA sequencing and was found to share significant homology with ra t and bovine PLCs of the 61 isotype. In situ hybridization showed that 30c7 transcripts were expressed in a small subpopulation of olfactory neurons, as well as in other cell types in the olfactory epithelium. Polymerase chain reaction (PCR) analysis indicated that the enzyme was also expressed in several additional tissues, including brain, gill, heart, liver and skeletal muscle. These results suggest that the PLC e ncoded by clone 30c7 is expressed in several tissues and therefore may have a role in mediating transduction events in diverse tissues as we ll as in a small group of olfactory neurons.