Enables succinate dehydrogenase (ubiquinone) activity. Involved in respiratory electron transport chain and succinate metabolic process. Located in mitochondrial inner membrane. Human ortholog(s) of this gene implicated in Carney-Stratakis syndrome; gastrointestinal stromal tumor; mitochondrial complex II deficiency; paraganglioma; and pheochromocytoma. Orthologous to human SDHB (succinate dehydrogenase complex iron sulfur subunit B). [provided by Alliance of Genome Resources, Apr 2022]