This gene encodes the beta chain of the branched chain alpha ketoacid dehydrogenase (Bckdh) complex. The encoded protein exists in a heterotetrameric complex containing the Bckdh alpha subunit to form the E1 catalytic component of Bckdh complex. The Bckdh complex catalyzes the oxidative decarboxylation of branched chain ketoacids to their corresponding acyl-CoA esters, during the catabolism of leucine, isoleucine and valine. In humans, certain mutations in this gene cause maple syrup urine disease. Alternative splicing results in multiple transcript variants encoding different isoforms. A pseudogene for this gene has been identified. [provided by RefSeq, Apr 2015]