Calcium/ Calmodulin Activated Kinases in Smooth Muscle

项目概述：这个正在进行的研究项目旨在定义多功能的功能

Project Summary: This ongoing research project is aimed at defining functions of multi-functional serine/threonine Ca2+/Calmodulin-dependent protein kinase II (CaMKII) isozymes in injury- and disease- induced vascular remodeling. CaMKII is structurally complex and is expressed as a large hetero-multimeric holoenzyme with 12-14 individual kinase subunits. CAMK2 genes undergo extensive alternative splicing to produce variants that can affect holoenzyme subcellular localization and protein interactions. The central hypothesis is that cell-specific expression and activation of CaMKII isoforms and splice variants are functional determinants of integrated vascular remodeling in response to injury and disease. The first specific aim extends our expertise in CaMKII structure and function in vascular smooth muscle to the vascular endothelium, in the context of an in vivo mouse model of intraluminal arterial injury that simulates aspects of in-stent restenosis. The functions of vascular endothelial cell CaMKII isoforms in re- endothelialization following intraluminal injury are tested by conditional knockout of specific Camk2 genes in genetically engineered mice. Regulation of the CaMKII isoform by STAT3 and the role of CaMKII in mediating STAT3-dependent functions are tested in this inflammatory environment. The second specific aim capitalizes on knowledge of CaMKII variant expression in vascular smooth muscle and tests the functional significance of an alternatively spliced c-terminal amino acid sequence in CaMKIIthat mediates formation of a CaMKII/Fyn complex, and subsequent regulation of cellular processes involved in vascular smooth muscle cell motility and proliferation A novel CaMKII antisense exon-skipping oligonucleotide (ESO) approach, designed to precisely interfere with expression of this sequence has been validated in vitro. ESOs will be administered to mice prior to intraluminal arterial injury with the goal of limiting vascular smooth muscle migration to the intima and subsequent neointimal hyperplasia, without affecting vasculoprotective endothelial regeneration. The final aim investigates the function of CaMKII isoforms in promoting programmed cell death by necroptosis in vascular smooth muscle and the role of this mechanism is promoting progression of abdominal aortic aneurysm. This aim is carried out in collaboration with labs at Augusta University and the University of Wisconsin and is investigated using mouse models of aortic aneurysm and conditional knockout of specific Camk2 genes in vascular smooth muscle. Relevance: Accomplishing these aims will provide detailed information on the functional importance of specific CaMKII isoform variants in vascular injury, in stent-restenosis and aneurysmal disease. Application of antisense ESOs targeting CaMKII may provide novel therapeutic approaches to mitigate progression of vascular disease.