Nuclear Modifier Gene Trmu Knockout Affects The Mitochondrial Function And Leads To Hair Cells Defects In Zebrafish

We established the trmuko mutant zebrafish by using the CRISPR-Cas9 system.Using this model,we explored the affect of hair cells and mitochondrial function in zebrafish.The numbers of lateral line neuromasts and hair cells in neuromasts are observably decreased in the trmuko mutant zebrafish.In addition,trmuko mutant zebrafish exhibited a decline in ATP generation and membrance potential,and the production of reactive oxygen species(ROS)decreased in mutant zebrafish.The levels of apoptosis are also decreased in adult zebrafish innear hair cells.These results shown the mitochondrial function are markedly damaged,and the numbers of hair cells are also decreased in trmuko zebrafish.Found trmu gene expressed in the inner ear,lateral line neuromasts,liver,swimming bladder,heart,by through using the ISH at 5dpf zebrafish.The mitochondria shown the abnormal structure in trmu matunt zebrafish.The numbers of mitochondria cristae are significantly decreased in the mutant zebrafish.The inner membrane begins to coalesce,followed by rarefaction(loss of density)of the matrix,and finally degradation of cristae.The wild type,heterozygous and homozygous zebrafish at 5dpf were stained with the vital dyes FM1-43FX and DASPEI at room temperature.After stained with FM1-43FX,we counted the neuromasts numbers of ALL and PLL,and also counted the numbers of hair cells in single neuromast.The numbers of neuromasts and hair cells are also decreased in mutant zebrafish;the results of DASPEI shown the hair cells are significantly damaged in mutant zebrafish.