ReSCUE (rephosphorylation of SR proteins by Clk urgent expression), a model for homeostatic control of SR protein phosphorylation. (1 and 2) A stress induces dephosphorylation of SR proteins (1) followed by promotion of stress-responsive splicing of intron-retaining Clk1/4 RNAs (2). (3) Clk1/4 proteins translated from newly matured Clk1/4 mRNAs rephosphorylate SR proteins.