... aprotinin, leupeptin and pepstatin, twice in kinase buffer, and used for in vitro kinase assays. In vitro kinase assaysRecombinant human protein kinase CK2 holoenzyme(0.5 U, corresponding to ... progression through the G1phase [11].Keywords atypical protein kinase; casein kinase 2substrate; cell-cycle phase-dependent degradation; protein protein interactions;Rio1 protein kinase 21CorrespondenceM. ... Protein kinase CK2 activates the atypical Rio1p kinase and promotes its cell-cycle phase-dependent degradation in yeast Michaela Angermayr1,*, Elisabeth Hochleitner2,†, Friedrich Lottspeich2and...