Gene Summary: Adenylsuccinate lyase is involved in both de novo synthesis of purines and formation of adenosine monophosphate from inosine monophosphate. ADSL catalyzes two reactions in AMP biosynthesis: the removal of a fumarate from succinylaminoimidazole carboxamide (SAICA) ribotide to give aminoimidazole carboxamide ribotide (AICA) and removal of fumarate from adenylosuccinate to give AMP. Adenylsuccinate lyase deficiency results in succinylpurinemic autism, psychomotor retardation, and , in some cases, growth retardation associated with muscle wasting and epilepsy. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]General information above from NCBI
Catalytic activity: N(6)-(1,2-dicarboxyethyl)AMP = fumarate + AMP.
(S)-2-(5-amino-1-(5-phospho-D- ribosyl)imidazole-4-carboxamido)succinate = fumarate + 5-amino-1- (5-phospho-D-ribosyl)imidazole-4-carboxamide.
Enzyme regulation: The enzyme reaction kinetics indicate cooperativity between subunits.
Subunit structure: Homotetramer. Residues from neighboring subunits contribute catalytic and substrate-binding residues to each active site.
Tissue specificity: Ubiquitously expressed. Both isoforms are produced by all tissues. Isoform 2 is 10-fold less abundant than isoform 1.
Involvement in disease: Adenylosuccinase deficiency (ADSL deficiency) [MIM:103050]: An autosomal recessive disorder characterized by the accumulation in the body fluids of succinylaminoimidazole- carboxamide riboside (SAICA-riboside) and succinyladenosine (S- Ado). Most children display marked psychomotor delay, often accompanied by epilepsy or autistic features, or both, although some patients may be less profoundly retarded. Occasionally, growth retardation and muscular wasting are also present. Note=The disease is caused by mutations affecting the gene represented in this entry.
Sequence similarity: Belongs to the lyase 1 family. Adenylosuccinate lyase subfamily.
General information above from UniProt