Angiotensinogen

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Angiotensinogen
Properties of human protein
Mass / length primary structure 452 aa; 49.8 kDa
Identifier
Gene names AGT  ; ANHU; SERPINA8
External IDs
Occurrence
Homology family HBG004233
Parent taxon Euteleostomi
Orthologue
human mouse
Entrez 183 11606
Ensemble ENSG00000135744 ENSMUSG00000031980
UniProt P01019 Q3UTR7
Refseq (mRNA) NM_000029 NM_007428
Refseq (protein) NP_031454
Gene locus Chr 1: 228.9 - 228.92 Mb Chr 8: 124.56 - 124.57 Mb
PubMed search 183 11606

Angiotensinogen is a protein and prohormone with 452 amino acids that is converted by the enzyme renin into the ten amino acid peptide angiotensin I (so - called post - translational modification ); from this, further angiotensins can be produced, each of which has specific biological functions.

Protein synthesis

After translation by hepatocytes and transport to the liver cell membrane, the signal sequence is separated from the protein chain and the resulting angiotensinogen is released into the plasma. The angiotensinogen produced in the liver circulates in human blood plasma. During the electrophoretic separation of the serum proteins , it migrates with the α 2 -globulin fraction.

The primary structure of human angiotensinogen consists of 452 amino acids with a molecular mass of 49,761 Da . The gene is on the long arm of chromosome 1 . From this the decapeptide angiotensin I is formed by enzymatic cleavage of the ten N- terminal amino acids.

Angiotensinogen was first identified in mice in 1983 by Ohkubo et al. and in humans for the first time in 1984 by Kageyama et al. described.

Angiotensin I and Angiotensin II ( dome models )

function

Angiotensinogen is a precursor protein of the renin-angiotensin-aldosterone system (RAAS), which is important for blood pressure regulation . It delivers the peptide hormones of the angiotensins through enzymatic cleavage . Renin splits off angiotensin I. Angiotensin converting enzyme (ACE) splits angiotensin II from angiotensin I. The angiotensins III and IV can arise from I and II. ACE2 splits angiotensin II and produces angiotensin 1-7, which can also be produced from angiotensin I with the help of neprilysin . ACE2 also produces angiotensin 1-9 from angiotensin I. 

Pos.    10         20         30         40         50            480   485   Name
<—————— Signalpeptid (1-33) ———————><—————— Angiotensinogen (34-485) —————>   
MRKRAPQSEM APAGVSLRAT ILCLLAWAGL AAGDRVYIHP FHLVIHNEST ... ALHFLGRVAN PLSTA   
                                    DRVYIHP FHL                               Angiotensin I (1-10)
                                    DRVYIHP FH                                Angiotensin 1-9
                                    DRVYIHP F                                 Angiotensin II (1-8)
                                    ARVYIHP F                                 Angiotensin A
                                     RVYIHP F                                 Angiotensin III (2-8)
                                      VYIHP F                                 Angiotensin IV (3-8)
                                    DRVYIHP                                   Angiotensin 1-7

swell

  1. ↑ a b c UniProt P01019
  2. ↑ Ohkubo, H. et al. (1983): Cloning and sequence analysis of cDNA for rat angiotensinogen. In: Proc. Natl. Acad. Sci. USA Vol. 80, pp. 2196-2200. PMID 6572971
  3. ↑ Kageyama, R. et al. (1984): Primary structure of human preangiotensinogen deduced from the cloned cDNA sequence. In: Biochemistry. Vol. 23, pp. 3603-3609. PMID 6089875