| CHGA | |||||||||||||||||||||||||||||||||||||||||||||||||||
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| Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
| Aliases | CHGA, CGA, chromogranin A, Chromogranin A, PHES, PHE5 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| External IDs | OMIM: 118910 MGI: 88394 HomoloGene: 976 GeneCards: CHGA | ||||||||||||||||||||||||||||||||||||||||||||||||||
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| Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Chromogranin A or parathyroid secretory protein 1 (gene name CHGA) is a member of the granin family of neuroendocrine secretory proteins. As such, it is located in secretory vesicles of neurons and endocrine cells such as islet beta cell secretory granules in the pancreas. In humans, chromogranin A protein is encoded by the CHGA gene.
Tissue distribution
Examples of cells producing chromogranin A (ChgA) are chromaffin cells of the adrenal medulla, paraganglia, enterochromaffin-like cells and beta cells of the pancreas. It is present in islet beta cell secretory granules. chromogranin-A (CgA)+ Pulmonary neuroendocrine cells account for 0.41% of all epithelial cells in the conducting airway, but are absent from the alveoli.
Function
Chromogranin A is the precursor to several functional peptides including vasostatin-1, vasostatin-2, pancreastatin, catestatin and parastatin. These peptides negatively modulate the neuroendocrine function of the releasing cell (autocrine) or nearby cells (paracrine).
Chromogranin A induces and promotes the generation of secretory granules such as those containing insulin in pancreatic islet beta cells.
Clinical significance
Chromogranin A is elevated in pheochromocytomas. It has been identified as autoantigen in type 1 diabetes. A peptide fragment of ChgA located in the Vasostatin-1, namely ChgA29-42 has been identified as the antigenic epitope recognized by diabetogenic BDC2.5 T cells from type 1 diabetes prone NOD mice.
It is used as an indicator for pancreas and prostate cancer and in carcinoid syndrome. It might play a role in early neoplasic progression. Chromogranin A is cleaved by an endogenous prohormone convertase to produce several peptide fragments. See chromogranin A GeneRIFs for references. In immunohistochemistry it can be used to identify a range of neuroendocrine tumours and is highly specific for both benign and malignant cells of this type.
Mass spec data shows that several peptides originating from CHGA (163-194; 194–214; 272–295;) are significantly lower in samples from ulcerative colitis patients compared to control biopsies.
There are considerable differences in the amino acid composition between different species' chromogranin A . Commercial assays for measuring human CGA can usually not be used for measuring CGA in samples from other animals. Some specific parts of the molecule have a higher degree of amino acid homology and methods where the antibodies are directed against specific epitopes can be used to measure samples from different animals. Region-specific assays measuring defined parts of CGA, CGB and SG2 can be used for measurements in samples from cats and dogs. In dogs, the catestatin concentration showed weak negative associations with left atrial and ventricular sizes and the catestatin concentration showed weak positive associations with blood pressure.
Variants
Variants exist for pancreastatin in various populations of the world. The variant Glycine297Serine has been shown to be more potent in inhibiting insulin-induced glucose uptake, resulting in higher risk of insulin resistance and diabetes among carriers of this variant. A team of researchers led by the Indian Institute of Technology Madras has found that the Glycine297Serine variation was present in approximately 15 percent of Indian and other South Asian populations.
Further reading
- Hendy GN, Bevan S, Mattei MG, Mouland AJ (February 1995). "Chromogranin A". Clinical and Investigative Medicine. 18 (1): 47–65. PMID 7768066.
- Iacangelo AL, Eiden LE (August 1995). "Chromogranin A: current status as a precursor for bioactive peptides and a granulogenic/sorting factor in the regulated secretory pathway". Regulatory Peptides. 58 (3): 65–88. doi:10.1016/0167-0115(95)00069-N. PMID 8577930. S2CID 23202363.
- Curry WJ, Barkatullah SC, Johansson AN, Quinn JG, Norlen P, Connolly CK, et al. (October 2002). "WE-14, a chromogranin a-derived neuropeptide". Annals of the New York Academy of Sciences. 971 (1): 311–6. Bibcode:2002NYASA.971..311C. doi:10.1111/j.1749-6632.2002.tb04485.x. PMID 12438141. S2CID 22565635.
- Curry WJ, Shaw C, Johnston CF, Thim L, Buchanan KD (April 1992). "Isolation and primary structure of a novel chromogranin A-derived peptide, WE-14, from a human midgut carcinoid tumour". FEBS Letters. 301 (3): 319–21. doi:10.1016/0014-5793(92)80266-J. PMID 1577173. S2CID 11191027.
- Tamamura H, Ohta M, Yoshizawa K, Ono Y, Funakoshi A, Miyasaka K, et al. (July 1990). "Isolation and characterization of a tumor-derived human protein related to chromogranin A and its in vitro conversion to human pancreastatin-48". European Journal of Biochemistry. 191 (1): 33–9. doi:10.1111/j.1432-1033.1990.tb19090.x. PMID 2165909.
- Konecki DS, Benedum UM, Gerdes HH, Huttner WB (December 1987). "The primary structure of human chromogranin A and pancreastatin". The Journal of Biological Chemistry. 262 (35): 17026–30. doi:10.1016/S0021-9258(18)45486-5. PMID 2445752.
- Sekiya K, Ghatei MA, Minamino N, Bretherton-Watt D, Matsuo H, Bloom SR (February 1988). "Isolation of human pancreastatin fragment containing the active sequence from a glucagonoma". FEBS Letters. 228 (1): 153–6. doi:10.1016/0014-5793(88)80606-9. PMID 2830133. S2CID 36547482.
- Helman LJ, Ahn TG, Levine MA, Allison A, Cohen PS, Cooper MJ, et al. (August 1988). "Molecular cloning and primary structure of human chromogranin A (secretory protein I) cDNA". The Journal of Biological Chemistry. 263 (23): 11559–63. doi:10.1016/S0021-9258(18)37995-X. PMID 3403545.
- Wilson BS, Phan SH, Lloyd RV (February 1986). "Chromogranin from normal human adrenal glands: purification by monoclonal antibody affinity chromatography and partial N-terminal amino acid sequence" (PDF). Regulatory Peptides. 13 (3–4): 207–23. doi:10.1016/0167-0115(86)90040-6. hdl:2027.42/26277. PMID 3704195. S2CID 36060758.
- Deftos LJ, Murray SS, Burton DW, Parmer RJ, O'Connor DT, Delegeane AM, Mellon PL (May 1986). "A cloned chromogranin A (CgA) cDNA detects a 2.3Kb mRNA in diverse neuroendocrine tissues". Biochemical and Biophysical Research Communications. 137 (1): 418–23. doi:10.1016/0006-291X(86)91226-X. PMID 3718511.
- Hagn C, Schmid KW, Fischer-Colbrie R, Winkler H (October 1986). "Chromogranin A, B, and C in human adrenal medulla and endocrine tissues". Laboratory Investigation; A Journal of Technical Methods and Pathology. 55 (4): 405–11. PMID 3762065.
- Murray SS, Deaven LL, Burton DW, O'Connor DI, Mellon PL, Deftos LJ (January 1987). "The gene for human chromogranin A (CgA) is located on chromosome 14". Biochemical and Biophysical Research Communications. 142 (1): 141–6. doi:10.1016/0006-291X(87)90462-1. PMID 3814131.
- Cetin Y, Aunis D, Bader MF, Galindo E, Jörns A, Bargsten G, Grube D (March 1993). "Chromostatin, a chromogranin A-derived bioactive peptide, is present in human pancreatic insulin (beta) cells". Proceedings of the National Academy of Sciences of the United States of America. 90 (6): 2360–4. Bibcode:1993PNAS...90.2360C. doi:10.1073/pnas.90.6.2360. PMC 46086. PMID 8096340.
- Mouland AJ, Bevan S, White JH, Hendy GN (March 1994). "Human chromogranin A gene. Molecular cloning, structural analysis, and neuroendocrine cell-specific expression". The Journal of Biological Chemistry. 269 (9): 6918–26. doi:10.1016/S0021-9258(17)37462-8. PMID 8120054.
- Maruyama K, Sugano S (January 1994). "Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides". Gene. 138 (1–2): 171–4. doi:10.1016/0378-1119(94)90802-8. PMID 8125298.
- Simon-Chazottes D, Wu H, Parmer RJ, Rozansky DJ, Szpirer J, Levan G, et al. (July 1993). "Assignment of the chromogranin A (Chga) locus to homologous regions on mouse chromosome 12 and rat chromosome 6". Genomics. 17 (1): 252–5. doi:10.1006/geno.1993.1316. PMID 8406464.
- Mahata SK, Kozak CA, Szpirer J, Szpirer C, Modi WS, Gerdes HH, et al. (April 1996). "Dispersion of chromogranin/secretogranin secretory protein family loci in mammalian genomes". Genomics. 33 (1): 135–9. doi:10.1006/geno.1996.0171. PMID 8617499.
- Strub JM, Goumon Y, Lugardon K, Capon C, Lopez M, Moniatte M, et al. (November 1996). "Antibacterial activity of glycosylated and phosphorylated chromogranin A-derived peptide 173-194 from bovine adrenal medullary chromaffin granules". The Journal of Biological Chemistry. 271 (45): 28533–40. doi:10.1074/jbc.271.45.28533. PMID 8910482.
External links
- chromogranin A antibody stains via Google Image [1]
- Overview of all the structural information available in the PDB for UniProt: P10645 (Chromogranin-A) at the PDBe-KB.
- Overview of all the structural information available in the PDB for UniProt: P26339 (Mouse Chromogranin-A) at the PDBe-KB.