Disrupting the LINC complex by AAV mediated gene transduction prevents progression of Lamin induced cardiomyopathy
Ruth Jinfen Chai, Hendrikje Werner, Peter Yiqing Li, Yin Loon Lee, Khaing Thet Nyein, Irina Solovei, Tuan Danh Anh Luu, Bhavya Sharma, Raju Navasankari, Martina Maric, Lois Yu En Sim, Ying Jie Loh, Edita Aliwarga, Jason Wen Long Cheong, Alexandre Chojnowski, Matias Autio, Haiyang Yu, Kenneth K. B. Tan, Choong Tat Keng, Shi Ling Ng, Wei Leong Chew, Michael A. Ferenczi, Brian Burke, Roger Foo, Colin L. Stewart
Abstract
Mutations in the LaminA gene are a common cause of monogenic dilated cardiomyopathy. Here we show that mice with a cardiomyocyte-specific Lmna deletion develop cardiac failure and die within 3-4 weeks after inducing the mutation. When the same Lmna mutations are induced in mice genetically deficient in the LINC complex protein SUN1, life is extended to more than one year. Disruption of SUN1's function is also accomplished by transducing and expressing a dominant-negative SUN1 miniprotein in Lmna deficient cardiomyocytes, using the cardiotrophic Adeno Associated Viral Vector 9. The SUN1 miniprotein disrupts binding between the endogenous LINC complex SUN and KASH domains, displacing the cardiomyocyte KASH complexes from the nuclear periphery, resulting in at least a fivefold extension in lifespan. Cardiomyocyte-specific expression of the SUN1 miniprotein prevents cardiomyopathy progression, potentially avoiding the necessity of developing a specific therapeutic tailored to treating each different LMNA cardiomyopathy-inducing mutation of which there are more than 450.