NMR assignment of the cAMP-binding domain A of the PKA regulatory subunit.

Yeast two-hybrid screening and deletion mapping have revealed that the deletion mutant of the PKA regulatory subunit RIa(94–244) contains the primary determinants for the interaction with the catalytic subunit (Huang et al., 1998). Furthermore H/D exchange has shown that residues (94–118) are not significantly affected by cAMP (Anand et al., 2002). The RIa(119–244) domain is thus the minimal construct that contains the key structural elements necessary to understand the allosteric activation of PKA by cAMP. We have therefore initiated the NMR investigation of RIa(119–244). A total of 1262 H, C and N assignments were made for RIa(119–244) resulting in an average of 10 assignments per residue. Specifically, more than 97% of all backbone resonances and more than 78% of all side chain resonances were identified, including the assignment of 89% of the H side chain resonances. BMRB accession number 6984. References: Huang et al. (1998) J. Biol. Chem., 273, 26739–26746; Anand et al. (2002) J. Mol. Biol., 323, 377–386.