SerpinA3

Although its physiological function is unclear, SerpinA3 can inhibit neutrophil cathepsin G and mast cell chymase, both of which can convert angiotensin-1 to the active angiotensin-2.

SerpinA3 Related Areas

Enzyme>>Protease & Regulator>>Serine Protease & Regulator>>Serpin Superfamily>>SerpinA3

Immunology>>Innate Immunity>>Acute Phase Proteins>>SerpinA3

SerpinA3 Alternative Names

SERPINA3, alpha-1-antichymotrypsin, AACT, ACT, GIG24, GIG25, MGC88254 [Homo sapiens]

Summaries for SerpinA3

Entrez Gene summary for SerpinA3:

The protein encoded by SerpinA3 gene is a plasma protease inhibitor and member of the serine protease inhibitor class. Polymorphisms in this protein appear to be tissue specific and influence protease targeting. Variations in this protein's sequence have been implicated in Alzheimer's disease, and deficiency of this protein has been associated with liver disease. Mutations have been identified in patients with Parkinson disease and chronic obstructive pulmonary disease. [provided by RefSeq, Jul 2008]

OMIM - description for SerpinA3:

Alpha-1-antichymotrypsin is a plasma protease inhibitor synthesized in the liver. It is a single glycopeptide chain of about 68,000 daltons and belongs to the class of serine protease inhibitors. In man, the normal serum level is about one-tenth that of alpha-1-antitrypsin (PI), with which it shares nucleic acid and protein sequence homology (Chandra et al., 1983). Both are major acute phase reactants; their concentrations in plasma increase in response to trauma, surgery, and infection. Antithrombin III, which also is structurally similar to alpha-1-antitrypsin, shows less sequence homology to antichymotrypsin and is not an acute phase reactant.

Wikipedia summary for SerpinA3:

SerpinA3 is an alpha globulin glycoprotein that is a member of the serpin superfamily.
It inhibits the activity of certain enzymes called proteases, such as cathepsin G that is found in neutrophils, and chymases found in mast cells, by cleaving them into a different shape or conformation. This activity protects some tissues, such as the lower respiratory tract, from damage caused by proteolytic enzymes.
This protein is produced in the liver, and is an acute phase protein that is induced during inflammation. Deficiency of this protein has been associated with liver disease. Mutations have been identified in patients with Parkinson disease and chronic obstructive pulmonary disease.
SerpinA3 is also associated with the pathogenesis of Alzheimer's disease as it enhances the formation of amyloid-fibrils in this disease.

Human SerpinA3 Protein General Information

 

• Protein names: SERPINA3
• Sequence length: 423 AA.
• Domain: The reactive center loop (RCL) extends out from the body of the protein and directs binding to the target protease. The protease cleaves the serpin at the reactive site within the RCL, establishing a covalent linkage between the carboxyl group of the serpin reactive site and the serine hydroxyl of the protease. The resulting inactive serpin-protease complex is highly stable.
• Sequence similarities: Belongs to the serpin family.
• Miscellaneous: Alpha-1-antichymotrypsin can bind DNA.
• Subunit structure: Interacts with DNAJC1.
• Subcellular location: Secreted.
• Tissue specificity: Plasma. Synthesized in the liver. Like the related alpha-1-antitrypsin, its concentration increases in the acute phase of inflammation or infection. Found in the amyloid plaques from the hippocampus of Alzheimer disease brains.
• Caution: It is uncertain whether Met-1 or Met-4 is the initiator.
• Sequence caution: The sequence AAA51543.1 differs from that shown. Reason: Frameshift at positions 101, 106, 111, 117, 123, 129 and 421.
  The sequence AAT08029.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally shortened.
  The sequence AAT08029.1 differs from that shown. Reason: Frameshift at position 4.
  The sequence BAD92297.1 differs from that shown. Reason: Erroneous initiation.
  The sequence CAA48671.1 differs from that shown. Reason: Erroneous initiation.

General information above from UniProt

Function for SerpinA3 Protein

UniProtKB:

Although its physiological function is unclear, SerpinA3 can inhibit neutrophil cathepsin G and mast cell chymase, both of which can convert angiotensin-1 to the active angiotensin-2.

Genatlas:

• SerpinA3 inhibits the activity of cathepsin G (release of neutrophil cathepsin G can destroy the vascular matrix through degradation, platelet aggregation and coagulation disorders)
• SerpinA3 is inhibitor that controls proMMP-9 activation in skin tissue

Homology for human SerpinA3

• homolog to rattus spin2c
• homolog to murine Spin2c

Phenotype Information for SerpinA3

• Gene/Locus: SERPINA3, AACT, ACT
• Phenotype: Alpha-1-antichymotrypsin deficiency
  Cerebrovascular disease, occlusive

Phenotype Information for SerpinA3 from OMIM (Online Mendelian Inheritance in Man)