Enables L-malate dehydrogenase activity; malate dehydrogenase (NADP+) activity; and protein self-association. Involved in NADH metabolic process; dicarboxylic acid metabolic process; and tricarboxylic acid cycle. Located in mitochondrial matrix. Used to study brain ischemia; congestive heart failure; and myocardial infarction. Human ortholog(s) of this gene implicated in developmental and epileptic encephalopathy 51. Orthologous to human MDH2 (malate dehydrogenase 2). [provided by Alliance of Genome Resources, Apr 2022]