Structural and functional analyses of the N-terminal domain of the A subunit of a spore germinant receptor.

Germination of spores is induced by the interaction of specific nutrient molecules with germinant receptors (GRs) localized in the spore's inner membrane. GRs typically consist of three subunits referred to as A, B, and C, although functions of individual subunits are not known. Here we present the crystal structure of the N-terminal domain (NTD) of the A subunit of the GerK GR, revealing two distinct globular subdomains bisected by a cleft, a fold with strong homology to substrate-binding proteins in bacterial ABC transporters.

Spatiotemporal regulation of PKC via interactions with AKAP7 isoforms.

The regulation of kinases by scaffolding proteins greatly contributes to the fidelity of signal transduction. In the present study, we explored an interaction between the ubiquitous enzyme PKC (protein kinase C) and the scaffolding protein AKAP7 (A-kinase-anchoring protein 7). Using protein biochemistry and surface plasmon resonance approaches, we demonstrate that both AKAP7γ and AKAP7α are capable of high-affinity interactions with multiple isoenzymes of PKC.