Protein product of a human intronless calmodulinlike gene shows tissue-specific expression and reduced abundance in transformed cells. Cell Growth Differ

The recently identified NB-i mRNA is transcribed from a single intronless gene, previously thought to be an unexpressed calmodulin pseudogene. Although expression levels of the three known human calmodulin genes fluctuate only slightly in all cell types and tissues examined, NB- 1 expression is limited to certain cells of pseudostratified and stratified epithelial tissues. Like calmodulin, the protein encoded by NB-i is heat stable and binds to phenyl-Sepharose in a calcium-dependent manner. Despite the shared identity of 85 % of their 148 amino acids, however, calmodulin and NB-i protein are easily distinguished eledrophoretically and immunologically. Polyclonal antibodies prepared against recombinant NB-i protein recognize a protei