In Arabidopsis thaliana (L.) Heynh., the nucleoporin CPR5 negatively regulates the cell cycle regulator CKI. In this short communication, it is shown that a cpr5 mutant is hypersensitive to the plant stress hormones of jasmonic acid, abscisic acid, and ethylene, whereas a cki mutant (sim smr1) is insensitive to these hormones, suggesting that the CPR5–CKI signaling pathway plays a central role in integrating stress responses.