Enolases have been characterized as highly conserved cytoplasmic glycolytic enzymes that may be involved in differentiation. Three isoenzymes have been identified, alpha enolase, beta enolase and gamma enolase. alpha enolase expression has been detected on most tissues, whereas betaenolase is expressed predominantly in muscle tissue and gamma enolase is detected only in nervous tissue. These isoforms exist as both homodimers and heterodimers, and they play a role in converting phosphoglyceric acid to phosphenolpyruvic acid in the glycolytic pathway. ENO4 (Enolase-like protein ENO4), also known as C10orf134, is a 628 amino acid protein that belongs to the Enolase family. ENO4 is expressed as two isoforms produced by alternative splicing and is encoded by a gene mapping to human chromosome 10q25.3 and murine chromosome 19 D3.