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Membrane and Soluble Adenylyl Cyclases Generate Discrete cAMP Pools which Discriminate between Cytoskeletal Binding Proteins to Regulate Endothelial Barrier
Author(s) -
Sayner Sarah L.,
Prasain Nutan,
Balczon Ron,
Stevens Troy
Publication year - 2009
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.23.1_supplement.965.16
Subject(s) - adenylyl cyclase , microbiology and biotechnology , adcy10 , filamin , cytosol , cytoskeleton , forskolin , chemistry , phosphorylation , adcy9 , biology , biochemistry , biophysics , signal transduction , cell , receptor , enzyme
Transmembrane adenylyl cyclases generate a cAMP pool restricted to the sub‐plasma membrane compartment, which strengthens endothelial barrier integrity. In contrast, a eukaryotic dependent bacterial adenylyl cyclase, ExoY of P. aeruginosa , generates cytosolic cAMP that disrupts the endothelial barrier. Similarly, a soluble chimeric mammalian adenlyl cyclase generates forskolin sensitive cAMP in both the subplasma membrane and bulk cytosolic compartments and disrupts the barrier. The molecular targets responsible for the diverse actions of these two distinct cAMP microdomains ‐ plasma membrane versus cytosolic ‐ are unknown. Filamin, an actin binding protein, is PKA phosphorylated at Ser2152, thus stabilizing its association with actin, which strengthens the barrier. In contrast, tau stabilizes microtubules and is PKA phosphorylated at Ser214 destabilizing microtubules sufficient to disrupt the endothelial barrier. We found that activation of transmembrane adenylyl cyclase leads to phosphorylation of filamin2152, while activation of cytosolic adenylyl cyclase induces phosphorylation of tau214. These data suggest that the barrier enhancing properties of subplasma membrane cAMP are transduced via filamin mediated stabilization of actin while barrier disruptive properties of cytosolic cAMP are transduced via tau mediated disruption of microtubules. Supported by HL66299 and F32HL091651promotes orthogonal branching of F‐actin and links microfilaments to membrane glycoprotein.