Autoregulation of the LIM kinases by their PDZ domain
Abstract LIM domain kinases (LIMK) are important regulators of actin cytoskeletal remodeling. These protein kinases phosphorylate the actin depolymerizing factor cofilin to suppress filament severing, and are key nodes between Rho GTPase cascades and actin. The two mammalian LIMKs, LIMK1 and LIMK2,...
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2023-12-01
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| Series: | Nature Communications |
| Online Access: | https://doi.org/10.1038/s41467-023-44148-4 |
| _version_ | 1797376932926455808 |
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| author | Gabriela Casanova-Sepúlveda Joel A. Sexton Benjamin E. Turk Titus J. Boggon |
| author_facet | Gabriela Casanova-Sepúlveda Joel A. Sexton Benjamin E. Turk Titus J. Boggon |
| author_sort | Gabriela Casanova-Sepúlveda |
| collection | DOAJ |
| description | Abstract LIM domain kinases (LIMK) are important regulators of actin cytoskeletal remodeling. These protein kinases phosphorylate the actin depolymerizing factor cofilin to suppress filament severing, and are key nodes between Rho GTPase cascades and actin. The two mammalian LIMKs, LIMK1 and LIMK2, contain consecutive LIM domains and a PDZ domain upstream of the C-terminal kinase domain. The roles of the N-terminal regions are not fully understood, and the function of the PDZ domain remains elusive. Here, we determine the 2.0 Å crystal structure of the PDZ domain of LIMK2 and reveal features not previously observed in PDZ domains including a core-facing arginine residue located at the second position of the ‘x-Φ-G-Φ’ motif, and that the expected peptide binding cleft is shallow and poorly conserved. We find a distal extended surface to be highly conserved, and when LIMK1 was ectopically expressed in yeast we find targeted mutagenesis of this surface decreases growth, implying increased LIMK activity. PDZ domain LIMK1 mutants expressed in yeast are hyperphosphorylated and show elevated activity in vitro. This surface in both LIMK1 and LIMK2 is critical for autoregulation independent of activation loop phosphorylation. Overall, our study demonstrates the functional importance of the PDZ domain to autoregulation of LIMKs. |
| first_indexed | 2024-03-08T19:45:44Z |
| format | Article |
| id | doaj.art-c3531119e69c4b7a96f2d5730a4cef1c |
| institution | Directory Open Access Journal |
| issn | 2041-1723 |
| language | English |
| last_indexed | 2024-03-08T19:45:44Z |
| publishDate | 2023-12-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Nature Communications |
| spelling | doaj.art-c3531119e69c4b7a96f2d5730a4cef1c2023-12-24T12:23:16ZengNature PortfolioNature Communications2041-17232023-12-0114111310.1038/s41467-023-44148-4Autoregulation of the LIM kinases by their PDZ domainGabriela Casanova-Sepúlveda0Joel A. Sexton1Benjamin E. Turk2Titus J. Boggon3Department of Molecular Biophysics and Biochemistry, Yale UniversityDepartment of Pharmacology, Yale UniversityDepartment of Pharmacology, Yale UniversityDepartment of Molecular Biophysics and Biochemistry, Yale UniversityAbstract LIM domain kinases (LIMK) are important regulators of actin cytoskeletal remodeling. These protein kinases phosphorylate the actin depolymerizing factor cofilin to suppress filament severing, and are key nodes between Rho GTPase cascades and actin. The two mammalian LIMKs, LIMK1 and LIMK2, contain consecutive LIM domains and a PDZ domain upstream of the C-terminal kinase domain. The roles of the N-terminal regions are not fully understood, and the function of the PDZ domain remains elusive. Here, we determine the 2.0 Å crystal structure of the PDZ domain of LIMK2 and reveal features not previously observed in PDZ domains including a core-facing arginine residue located at the second position of the ‘x-Φ-G-Φ’ motif, and that the expected peptide binding cleft is shallow and poorly conserved. We find a distal extended surface to be highly conserved, and when LIMK1 was ectopically expressed in yeast we find targeted mutagenesis of this surface decreases growth, implying increased LIMK activity. PDZ domain LIMK1 mutants expressed in yeast are hyperphosphorylated and show elevated activity in vitro. This surface in both LIMK1 and LIMK2 is critical for autoregulation independent of activation loop phosphorylation. Overall, our study demonstrates the functional importance of the PDZ domain to autoregulation of LIMKs.https://doi.org/10.1038/s41467-023-44148-4 |
| spellingShingle | Gabriela Casanova-Sepúlveda Joel A. Sexton Benjamin E. Turk Titus J. Boggon Autoregulation of the LIM kinases by their PDZ domain Nature Communications |
| title | Autoregulation of the LIM kinases by their PDZ domain |
| title_full | Autoregulation of the LIM kinases by their PDZ domain |
| title_fullStr | Autoregulation of the LIM kinases by their PDZ domain |
| title_full_unstemmed | Autoregulation of the LIM kinases by their PDZ domain |
| title_short | Autoregulation of the LIM kinases by their PDZ domain |
| title_sort | autoregulation of the lim kinases by their pdz domain |
| url | https://doi.org/10.1038/s41467-023-44148-4 |
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