Background One mechanism that directs the action of the second messengers, cAMP and diacylglycerol, is the compartmentalization of protein kinase A (PKA) and protein kinase C (PKC). A-kinase anchoring proteins (AKAPs) can recruit both enzymes to specific subcellular locations via interactions with the various isoforms of each family of kinases. We found previously that a new class of AKAPs, dual-specific AKAPs, denoted D-AKAP1 and D-AKAP2, bind to RIα in addition to the RII subunits. Results Immunohistochemistry and confocal microscopy were used here to determine that D-AKAP1 colocalizes with RIα at the postsynaptic membrane of the vertebrate neuromuscular junction (NMJ) and the adjacent muscle, but not in the presynaptic region. The labeling pattern for RIα and D-AKAP1 overlapped with mitochondrial staining in the muscle fibers, consistent with our previous work showing D-AKAP1 association with mitochondria in cultured cells. The immunoreactivity of D-AKAP2 was distinct from that of D-AKAP1. We also report here that even though the PKA type II subunits (RIIα and RIIβ) are localized at the NMJ, their patterns are distinctive and differ from the other R and D-AKAP patterns examined. PKCβ appeared to colocalize with the AKAP, gravin, at the postsynaptic membrane. Conclusions The kinases and AKAPs investigated have distinct patterns of colocalization, which suggest a complex arrangement of signaling micro-environments. Because the labeling patterns for RIα and D-AKAP 1 are similar in the muscle fibers and at the postsynaptic membrane, it may be that this AKAP anchors RIα in these regions. Likewise, gravin may be an anchor of PKCβ at the NMJ.

The Rodent Research-3 (RR-3) mission was sponsored by the pharmaceutical company Eli Lilly and Co. and the Center for the Advancement of Science in Space to study the effectiveness of a potential countermeasure for the loss of muscle and bone mass that occurs during spaceflight. Twenty BALB/c 18-weeks old female mice (ten controls and ten treated) were flown to the ISS and housed in the AEM-X habitat for 39-42 days. Twenty mice of similar age sex and strain were used for ground controls housed in identical hardware and matching ISS environmental conditions. Basal controls were housed in standard vivarium cages. Spaceflight ground controls and basal groups had blood collected then were euthanized had one hind limb removed and finally whole carcasses were stored at -80 C until dissection. All mice in this data set received only the control/sham injection.

cell culture information with toxicity and proteomic changes. This dataset is associated with the following publication: VanEmon, J., P. Pan, and F. Van Breukelen. Effects of chlorpyrifos and trichloropyridinol on HEK 293 human embryonic kidney cells. CHEMOSPHERE. Elsevier Science Ltd, New York, NY, USA, 191: 537-547, (2018).