STAC, A NOVEL NEURON-SPECIFIC PROTEIN WITH CYSTEINE-RICH AND SH3 DOMAINS

In RLGS-M (restriction landmark genomic scanning using methylation-sen sitive endonuclease) displays of mouse brains, spot #91 is one tissue- specific gel spots whose intensity changes developmentally. The have n ow cloned the corresponding cDNA from this spot and analyzed its struc ture and expression. The deduced amino acid sequence revealed that the #91 cDNA encodes a novel protein of 403 amino acids which consists of a cysteine-rich domain and a SH3 domain. We designated this gene as S tac. Northern blotting and in situ hybridization analyses demonstrated that 2.7 kb of Stac mRNA is expressed predominantly in brain and neur ons, especially in hippocampus, cerebellum and inferior olive. Further , the gene product of 47 kDa was found by western blotting analysis in the soluble fractions of brain as well as Stac-expression vector-tran sfected NIH3T3 cells. Although the function of Stac is unknown so far, it is likely involved in a neuron-specific signal transduction. (C) 1 996 Academic Press.