Probable proline dehydrogenase 2 (PRODH2), also known as HSPOX1 or kidney and liver proline oxidase 1, is a 536 amino acid member of the proline oxidase family. The primary function of PRODH2 is to convert proline into delta-1-pyrroline-5-carboxylate (P5C). Proline, functioning as a source of glutamate, arginine and tricarboxylic acid cycle intermediates and taking part in shuttling redox equivalents between mitochondria and cytosol, plays a critical role in protein synthesis. P5C, with the help of ALDH4A1 (also known as 1-pyrroline-5-carboxylate dehydrogenase or P5CDH), is converted into glutamate, one of the most common neurotransmitters in the brain. The PRODH2 gene maps to chromosome 19q13.12, and mutations in this gene have been associated with increased susceptibility to schizophrenia.