Continuous phosphorylation of @entity13573 and @entity10929 by long-term @entity865 treatment in SK-N-SH @entity1 XXXX cells.

@entity1 @entity13573 @entity7131 @entity865 @entity521 @entity864 @entity493 @entity10929
Long-term treatment with @entity864 ( @entity865 ) down-regulates select @entity7131 ( @entity7131 ) isozymes and may differentially affect @entity7131 substrates. We investigated the role of @entity7131 down-regulation on phosphorylation of two @entity7131 substrates, the 43 kDa growth-associated protein ( @entity13573 ) and the myristoylated @entity493 -rich C-kinase substrate ( @entity10929 ) in SK-N-SH @entity1 @entity521 cells. Cells were treated with 70 nM @entity865 for 15 min, 17 or 72 h. Phosphorylation of @entity10929 and @entity13573 was elevated throughout 72 h of @entity865 . The magnitude and peptidic sites of phosphorylation in @entity13573 and @entity10929 were similar after all @entity865 treatments. @entity13573 , but not @entity10929 , content was increased after 17 and 72 h of @entity865 . The ratio of @entity13573 phosphorylation to content was elevated throughout 17 h but returned to control by 72 h as content increased. @entity7131 epsilon and alpha isozyme content was greatly reduced after 72 h of @entity865 but membranes retained 23% of @entity7131 activity. Only @entity7131 epsilon translocated to membranes after 15 min @entity865 . @entity13573 content after 72 h of @entity865 was increased in subcellular fractions in which significant @entity7131 epsilon isozyme concentration remained. These results demonstrate that continuous @entity865 differentially affected phosphorylation of @entity7131 substrate proteins and regulation of @entity7131 isozyme content in SK-N-SH cells.
