Phosphatases control PKA-dependent functional microdomains at the outer mitochondrial membrane
Evidence supporting the heterogeneity in cAMP and PKA signaling is rapidly accumulating and has been largely attributed to the localization or activity of adenylate cyclases, phosphodiesterases, and A-kinase–anchoring proteins in different cellular subcompartments. However, little attention has been...
| Main Authors: | , , , , , , , , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
National Academy of Sciences
2018
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| _version_ | 1797055931795636224 |
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| author | Burdyga, A Surdo, N Monterisi, S Di Benedetto, G Grisan, F Penna, E Pellegrini, L Bortolozzi, M Swietach, P Pozzan, T Lefkimmiatis, K |
| author_facet | Burdyga, A Surdo, N Monterisi, S Di Benedetto, G Grisan, F Penna, E Pellegrini, L Bortolozzi, M Swietach, P Pozzan, T Lefkimmiatis, K |
| author_sort | Burdyga, A |
| collection | OXFORD |
| description | Evidence supporting the heterogeneity in cAMP and PKA signaling is rapidly accumulating and has been largely attributed to the localization or activity of adenylate cyclases, phosphodiesterases, and A-kinase–anchoring proteins in different cellular subcompartments. However, little attention has been paid to the possibility that, despite homogeneous cAMP levels, a major heterogeneity in cAMP/PKA signaling could be generated by the spatial distribution of the final terminators of this cascade, i.e., the phosphatases. Using FRET-based sensors to monitor cAMP and PKA-dependent phosphorylation in the cytosol and outer mitochondrial membrane (OMM) of primary rat cardiomyocytes, we demonstrate that comparable cAMP increases in these two compartments evoke higher levels of PKA-dependent phosphorylation in the OMM. This difference is most evident for small, physiological increases of cAMP levels and with both OMM-located probes and endogenous OMM proteins. We demonstrate that this disparity depends on differences in the rates of phosphatase-dependent dephosphorylation of PKA targets in the two compartments. Furthermore, we show that the activity of soluble phosphatases attenuates PKA-driven activation of the cAMP response element-binding protein while concurrently enhancing PKA-dependent mitochondrial elongation. We conclude that phosphatases can sculpt functionally distinct cAMP/PKA domains even in the absence of gradients or microdomains of this messenger. We present a model that accounts for these unexpected results in which the degree of PKA-dependent phosphorylation is dictated by both the subcellular distribution of the phosphatases and the different accessibility of membrane-bound and soluble phosphorylated substrates to the cytosolic enzymes. |
| first_indexed | 2024-03-06T19:16:20Z |
| format | Journal article |
| id | oxford-uuid:18804f1a-9bc1-443b-b751-a8b4619cdbc2 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T19:16:20Z |
| publishDate | 2018 |
| publisher | National Academy of Sciences |
| record_format | dspace |
| spelling | oxford-uuid:18804f1a-9bc1-443b-b751-a8b4619cdbc22022-03-26T10:43:41ZPhosphatases control PKA-dependent functional microdomains at the outer mitochondrial membraneJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:18804f1a-9bc1-443b-b751-a8b4619cdbc2EnglishSymplectic Elements at OxfordNational Academy of Sciences2018Burdyga, ASurdo, NMonterisi, SDi Benedetto, GGrisan, FPenna, EPellegrini, LBortolozzi, MSwietach, PPozzan, TLefkimmiatis, KEvidence supporting the heterogeneity in cAMP and PKA signaling is rapidly accumulating and has been largely attributed to the localization or activity of adenylate cyclases, phosphodiesterases, and A-kinase–anchoring proteins in different cellular subcompartments. However, little attention has been paid to the possibility that, despite homogeneous cAMP levels, a major heterogeneity in cAMP/PKA signaling could be generated by the spatial distribution of the final terminators of this cascade, i.e., the phosphatases. Using FRET-based sensors to monitor cAMP and PKA-dependent phosphorylation in the cytosol and outer mitochondrial membrane (OMM) of primary rat cardiomyocytes, we demonstrate that comparable cAMP increases in these two compartments evoke higher levels of PKA-dependent phosphorylation in the OMM. This difference is most evident for small, physiological increases of cAMP levels and with both OMM-located probes and endogenous OMM proteins. We demonstrate that this disparity depends on differences in the rates of phosphatase-dependent dephosphorylation of PKA targets in the two compartments. Furthermore, we show that the activity of soluble phosphatases attenuates PKA-driven activation of the cAMP response element-binding protein while concurrently enhancing PKA-dependent mitochondrial elongation. We conclude that phosphatases can sculpt functionally distinct cAMP/PKA domains even in the absence of gradients or microdomains of this messenger. We present a model that accounts for these unexpected results in which the degree of PKA-dependent phosphorylation is dictated by both the subcellular distribution of the phosphatases and the different accessibility of membrane-bound and soluble phosphorylated substrates to the cytosolic enzymes. |
| spellingShingle | Burdyga, A Surdo, N Monterisi, S Di Benedetto, G Grisan, F Penna, E Pellegrini, L Bortolozzi, M Swietach, P Pozzan, T Lefkimmiatis, K Phosphatases control PKA-dependent functional microdomains at the outer mitochondrial membrane |
| title | Phosphatases control PKA-dependent functional microdomains at the outer mitochondrial membrane |
| title_full | Phosphatases control PKA-dependent functional microdomains at the outer mitochondrial membrane |
| title_fullStr | Phosphatases control PKA-dependent functional microdomains at the outer mitochondrial membrane |
| title_full_unstemmed | Phosphatases control PKA-dependent functional microdomains at the outer mitochondrial membrane |
| title_short | Phosphatases control PKA-dependent functional microdomains at the outer mitochondrial membrane |
| title_sort | phosphatases control pka dependent functional microdomains at the outer mitochondrial membrane |
| work_keys_str_mv | AT burdygaa phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT surdon phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT monterisis phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT dibenedettog phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT grisanf phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT pennae phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT pellegrinil phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT bortolozzim phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT swietachp phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT pozzant phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane AT lefkimmiatisk phosphatasescontrolpkadependentfunctionalmicrodomainsattheoutermitochondrialmembrane |