Differential distribution of the mRNA encoding two isoforms of the catalytic subunit of calcineurin in the rat brain.

The distribution of mRNAs encoding two distinct isoforms of the catalytic subunit of calmodulin-dependent protein phosphatase (calcineurin A), designated calcineurin A alpha and A beta, in the rat brain was examined by using Northern blots and in situ hybridization histochemistry. The mRNAs for calcineurin A alpha and A beta were both unevenly present in the brain and showed different distribution. The differential distribution between calcineurin A alpha and A beta messages suggests that the individual isoforms are involved in specialized neural functions.