Angiogenin (ANG) is a secreted ribonuclease originally identified as a potent angiogenic factor, but subsequently found to have critical functions in neuronal survival, stress response, and protein homeostasis. The protein is encoded by the ANG gene on chromosome 14q11.2 and is a member of the pancreatic ribonuclease family. While primarily studied in the context of cancer and angiogenesis, mutations in ANG have been strongly linked to amyotrophic lateral sclerosis (ALS) and [Parkinson's disease](/diseases/parkinsons-disease).
The 147-amino acid secreted protein has evolved additional functions beyond its angiogenic activity, including neuroprotection, modulation of rRNA transcription, and stress granule formation. These functions are particularly relevant to neurodegenerative diseases where cellular stress responses are compromised.[@strydom1998]
Angiogenin (ANG) is a secreted ribonuclease originally identified as a potent angiogenic factor, but subsequently found to have critical functions in neuronal survival, stress response, and protein homeostasis. The protein is encoded by the ANG gene on chromosome 14q11.2 and is a member of the pancreatic ribonuclease family. While primarily studied in the context of cancer and angiogenesis, mutations in ANG have been strongly linked to amyotrophic lateral sclerosis (ALS) and [Parkinson's disease](/diseases/parkinsons-disease).
The 147-amino acid secreted protein has evolved additional functions beyond its angiogenic activity, including neuroprotection, modulation of rRNA transcription, and stress granule formation. These functions are particularly relevant to neurodegenerative diseases where cellular stress responses are compromised.[@strydom1998]
Protein Name: ANG - Angiogenin, Ribonuclease 5
UniProt ID: P03950
Gene: [ANG](/proteins/ang-protein)
Molecular Weight: ~14 kDa (147 amino acids)
Protein Class: Secreted ribonuclease, Growth factor
Three conserved disulfide bonds: Stabilize structure
Despite having only ~35% sequence identity with RNase A, angiogenin retains catalytic activity, though with different substrate specificity and lower activity than pancreatic RNases.[@acharya1994]
Stress response: Incorporated into stress granules under stress
Neuroprotection: Supports neuronal survival under stress
Cell proliferation and differentiation: Multiple cellular effects
The neuroprotective functions of angiogenin are mediated through its ability to maintain protein synthesis capacity during stress and promote cell survival pathways.[@li2014]
Role in Neurodegeneration
Amyotrophic Lateral Sclerosis (ALS)
ALS gene: ANG mutations cause ~1-2% of familial ALS
Loss of function: Mutant angiogenin has reduced activity