Enables several functions, including ATP binding activity; lysine-tRNA ligase activity; and tRNA binding activity. Involved in several processes, including ERK1 and ERK2 cascade; diadenosine tetraphosphate biosynthetic process; and lysyl-tRNA aminoacylation. Located in cytosol and nucleus. Part of aminoacyl-tRNA synthetase multienzyme complex. Biomarker of sciatic neuropathy. Human ortholog(s) of this gene implicated in Charcot-Marie-Tooth disease recessive intermediate B and autosomal recessive nonsyndromic deafness 89. Orthologous to human KARS1 (lysyl-tRNA synthetase 1). [provided by Alliance of Genome Resources, Apr 2022]