Ser585 regulates the expression of specific genes. CTL-EN cells expressing either the wild-type βc or the βcSer585Gly mutant were stimulated with GM-CSF for the indicated times after which time total RNA was purified and subjected to Northern analysis by using ³²P-labeled cDNA probes (A). The Northern blot signals for each gene in CTL-EN cells expressing the wild-type βc (○) and βcSer585Gly mutant (Δ) were quantified by ImageQuant analysis from PhosphorImager screens and plotted as a percentage of the maximum signal observed (B).