3OF1

Crystal Structure of Bcy1, the Yeast Regulatory Subunit of PKA

Summary for 3OF1

• Entry DOI: 10.2210/pdb3of1/pdb
• Related: 1CX4 1RGS
• Descriptor: cAMP-dependent protein kinase regulatory subunit, ADENOSINE-3',5'-CYCLIC-MONOPHOSPHATE (3 entities in total)
• Functional Keywords: cyclic nucleotide binding domain, evolution, pka signaling, regulatory subunit, camp-dependent protein kinase, transferase
• Biological source: Saccharomyces cerevisiae (yeast)
• Cellular location: Cytoplasm: P07278
• Total number of polymer chains: 1
• Total formula weight: 28175.91

Authors

Rinaldi, J.,Wu, J.,Yang, J.,Ralston, C.Y.,Sankaran, B.,Moreno, S.,Taylor, S.S. (deposition date: 2010-08-13, release date: 2010-12-01, Last modification date: 2023-09-06)

Primary citation

Rinaldi, J.,Wu, J.,Yang, J.,Ralston, C.Y.,Sankaran, B.,Moreno, S.,Taylor, S.S.
Structure of Yeast Regulatory Subunit: A Glimpse into the Evolution of PKA Signaling.
Structure, 18:1471-1482, 2010

PubMed Abstract: The major cAMP receptors in eukaryotes are the regulatory (R) subunits of PKA, an allosteric enzyme conserved in fungi through mammals. While mammals have four R-subunit genes, Saccharomyces cerevisiae has only one, Bcy1. To achieve a molecular understanding of PKA activation in yeast and to explore the evolution of cyclic-nucleotide binding (CNB) domains, we solved the structure of cAMP-bound Bcy1(168-416). Surprisingly, the relative orientation of the two CNB domains in Bcy1 is very different from mammalian R-subunits. This quaternary structure is defined primarily by a fungi-specific sequence in the hinge between the αB/αC helices of the CNB-A domain. The unique interface between the two CNB domains in Bcy1 defines the allosteric mechanism for cooperative activation of PKA by cAMP. Some interface motifs are isoform-specific while others, although conserved, play surprisingly different roles in each R-subunit. Phylogenetic analysis shows that structural differences in Bcy1 are shared by fungi of the subphylum Saccharomycotina.

PubMed: 21070946
DOI: 10.1016/j.str.2010.08.013

Experimental method

X-RAY DIFFRACTION (2.21 Å)