Редактирование: HERC2

E3 ubiquitin-protein ligase HERC2 (EC 2.3.2.26) (HECT domain and RCC1-like domain-containing protein 2) (HECT-type E3 ubiquitin transferase HERC2)

==Publications==

{{medline-entry
|title=Endothelial [[SIRT1]] prevents adverse arterial remodeling by facilitating [[HERC2]]-mediated degradation of acetylated LKB1.
|pubmed-url=https://pubmed.ncbi.nlm.nih.gov/27259994
|abstract=Aims-[[SIRT1]] exerts potent activity against cellular senescence and vascular ageing. By decreasing LKB1 protein levels, it promotes the survival and regeneration of endothelial cells. The present study aims to investigate the molecular mechanisms underlying [[SIRT1]]-mediated LKB1 degradation for the prevention of vascular ageing.Methods and Results-Co-immunoprecipitation assay demonstrated that [[SIRT1]], via its amino-terminus, binds to the DOC domain of [[HERC2]] [HECT and RLD domain containing E3 ubiquitin protein ligase 2], which then ubiquitinates LKB1 in the nuclear compartment of endothelial cells. Site-directed mutagenesis revealed that acetylation at lysine (K) 64 of LKB1 triggers the formation of [[SIRT1]]/[[HERC2]]/LKB1 protein complex and subsequent proteasomal degradation. In vitro cellular studies suggested that accumulation of acetylated LKB1 in the nucleus leads to endothelial activation, in turn stimulating the proliferation of vascular smooth muscle cells and the production of extracellular matrix proteins. Chromatin immunoprecipitation quantitative PCR confirmed that acetylated LKB1 interacts with and activates TGFβ1 promoter, which is inhibited by [[SIRT1]]. Knocking down either [[SIRT1]] or [[HERC2]] results in an increased association of LKB1 with the positive regulatory elements of TGFβ1 promoter. In mice without endothelial nitric oxide synthase, selective overexpression of human [[SIRT1]] in endothelium prevents hypertension and age-related adverse arterial remodeling. Lentiviral-mediated knockdown of [[HERC2]] abolishes the beneficial effects of endothelial [[SIRT1]] on both arterial remodeling and arterial blood pressure control.Conclusion-By downregulating acetylated LKB1 protein via [[HERC2]], [[SIRT1]] fine-tunes the crosstalk between endothelial and vascular smooth muscle cells to prevent adverse arterial remodeling and maintain vascular homeostasis.
|mesh-terms=* 3T3-L1 Cells
* Acetylation
* Animals
* Arteries
* Carotid Arteries
* Cell Line, Tumor
* Endothelial Cells
* Endothelium, Vascular
* Guanine Nucleotide Exchange Factors
* Homeostasis
* Humans
* Mice
* Mice, Transgenic
* Muscle, Smooth, Vascular
* Mutagenesis, Site-Directed
* Nitric Oxide Synthase Type III
* Protein Processing, Post-Translational
* Protein-Serine-Threonine Kinases
* Sirtuin 1
* Ubiquitin
* Ubiquitin-Protein Ligases
* Vascular Remodeling
|keywords=* Gerotarget
* LKB1
* SIRT1
* blood vessel remodeling
* endothelial senescence
* hypertension
|full-text-url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5129914
}}