G1/S cyclins interact with regulatory subunit of PKA via A-kinase anchoring protein, AKAP95

The mechanisms by which cyclins promote mammalian cell cycle progression have been a topic of intense investigation over the last decade. We previously described an interaction between D-type cyclins and A-kinase anchoring protein, AKAP95. Here, we demonstrate that AKAP95 can also bind cyclin E1. Association between AKAP95 and cyclins is displaced by CDKs. We show that these G(1)/S cyclins can interact with RII subunit of PKA alpha through AKAP95. The presence of alternate complexes cyclin-CDK and cyclin D/E-AKAP95-PKA. RII alpha suggest different roles of G(1)/S cyclins and a wider biological importance of these interactions in cells.