Alternative titles; symbols
HGNC Approved Gene Symbol: GZMA
Cytogenetic location: 5q11.2 Genomic coordinates (GRCh38): 5:55,102,646-55,110,252 (from NCBI)
Cytolytic T lymphocytes (CTLs) and natural killer (NK) cells share the remarkable ability to recognize, bind, and lyse specific target cells. They are thought to protect their host by lysing cells bearing on their surface 'nonself' antigens, usually peptides or proteins resulting from infection by intracellular pathogens, e.g., viruses. Recombinant DNA techniques have been used to select genes preferentially expressed in CTL cells. Gershenfeld and Weissman (1986) cloned a mouse CTL cDNA encoding a trypsin-like serine protease. They called the substance Hanukah factor because its nucleotide sequence bore similarities to that of blood coagulation factor IX (300746), which was named Christmas factor. This serine protease is also called granzyme A (Masson and Tschopp, 1987).
Held et al. (1990) studied the expression of the gene for granzyme A during the development of spontaneous diabetes mellitus in the mouse, where progressive destruction of the insulin-producing beta cells occurs after infiltration of the pancreas with lymphocytes.
Gershenfeld et al. (1988) obtained a cDNA clone encoding a human T cell- and natural killer cell-specific serine protease by screening a phage cDNA library from phytohemagglutinin-stimulated human peripheral blood lymphocytes with the mouse Hanukah factor cDNA clone. The nucleotide sequence of this cDNA clone predicts a serine protease of 262 amino acids with a calculated unglycosylated molecular weight of 25,820. They proposed that this trypsin-like serine protease functions in the lysis of target cells by cytotoxic T lymphocytes and natural killer cells.
GZMA induces caspase-independent apoptosis in a characteristic manner, except it causes a distinctive form of DNA damage: single-stranded DNA nicking. A target of GZMA is the SET (600960) complex, including HMGB2 (163906) and ANP32A (600832). Fan et al. (2003) showed that APEX (107748) is also present in the SET complex and binds to GZMA. GZMA cleaves APEX after lys31, destroying its known oxidative repair functions. Silencing of APEX expression by RNA interference nearly doubled specific cell lysis, with enhanced DNA nicking. Mutation analysis indicated that lys31 is crucial for GZMA cleavage of APEX and GZMA-induced cell death.
A GZMA-activated DNase (GAAD) is in an endoplasmic reticulum-associated complex containing pp32 and the GZMA substrates SET, HMG2, and APE1. Fan et al. (2003) showed that GAAD is NM23H1 (156490), a nucleoside diphosphate kinase implicated in suppression of tumor metastasis, and its specific inhibitor (IGAAD) is SET. NM23H1 bound SET and was released from inhibition by GZMA cleavage of SET. After GZMA loading or cytotoxic T lymphocyte attack, SET and NM23H1 translocated to the nucleus and SET was degraded, allowing NM23H1 to nick chromosomal DNA. GZMA-treated cells with silenced NM23H1 expression were resistant to GZMA-mediated DNA damage and cytolysis, while cells overexpressing NM23H1 were more sensitive.
Using human and mouse cells and tissues, Martinvalet et al. (2008) found that GZMA activated mitochondrial outer membrane permeabilization- and caspase-independent cell death pathways by cleaving the mitochondrial complex I component NDUFS3 (603846) after lys56. NDUFS3 cleavage generated reactive oxygen species, disrupted the mitochondrial membrane potential, and interfered with NADH oxidation and ATP synthesis. The generation of reactive oxygen species induced translocation of the SET complex from the cytosol to the nucleus, followed by GZMA-mediated activation of the SET complex DNases NM23H1 and TREX1 (606609), leading to DNA damage and cell death. SET complex translocation, DNase activation, and cell death were blocked by superoxide scavengers or by overexpression of a cleavage-resistant NDUFS3 mutant. GZMA required the cytolytic protein perforin (PRF1; 170280) for delivery to the cell cytosol, and it required the mitochondrial membrane potential to translocate to the mitochondrial matrix, possibly via the cytosolic chaperones HSP70 (see HSPA1A; 140550) or HSP90 (see HSP90AA1; 140571), with which it immunoprecipitated in vitro. Martinvalet et al. (2008) concluded that cleavage of NDUFS3 is the first step in GZMA-induced cell death.
Zhou et al. (2020) reported that natural killer cells and cytotoxic T lymphocytes kill gasdermin B (GSDMB; 611221)-positive cells through pyroptosis, a form of proinflammatory cell death executed by the gasdermin family of pore-forming proteins. Killing results from the cleavage of GSDMB by lymphocyte-derived GZMA, which unleashes its pore-forming activity. Interferon-gamma (IFNG; 147570) upregulates GSDMB expression and promotes pyroptosis. GSDMB is highly expressed in certain tissues, particularly digestive tract epithelia, including derived tumors. Introducing GZMA-cleavable GSDMB into mouse cancer cells promoted tumor clearance in mice. Zhou et al. (2020) concluded that their study established gasdermin-mediated pyroptosis as a cytotoxic lymphocyte-killing mechanism, which may enhance antitumor immunity.
Fink et al. (1993) isolated a cosmid clone for the CTLA3 gene and established its complete exon-intron map of 10 kb.
Ebnet et al. (1992) demonstrated that the mouse gene consists of 5 exons and that its genomic organization is very similar to that described for granzymes B, C, and F.
By hybridization to DNA from somatic cell hybrids, Gershenfeld et al. (1988) demonstrated that the CTLA3 gene is located on chromosome 5. By fluorescence in situ hybridization to metaphase chromosomes, Fink et al. (1993) assigned the gene to 5q11-q12. By fluorescence in situ hybridization, Baker et al. (1994) also mapped the HFSP gene to 5q11-q12. Justice et al. (1990) demonstrated that the mouse homolog of CTLA3 is located on chromosome 13.
Baker, E., Sayers, T. J., Sutherland, G. R., Smyth, M. J. The genes encoding NK cell granule serine proteases, human tryptase-2 (TRYP2) and human granzyme A (HFSP), both map to chromosome 5q11-q12 and define a new locus for cytotoxic lymphocyte granule tryptases. Immunogenetics 40: 235-237, 1994. [PubMed: 8039831] [Full Text: https://doi.org/10.1007/BF00167085]
Ebnet, K., Kramer, M. D., Simon, M. M. Organization of the gene encoding the mouse T-cell-specific serine proteinase 'granzyme A'. Genomics 13: 502-508, 1992. [PubMed: 1639378] [Full Text: https://doi.org/10.1016/0888-7543(92)90117-b]
Fan, Z., Beresford, P. J., Oh, D. Y., Zhang, D., Lieberman, J. Tumor suppressor NM23-H1 is a granzyme A-activated DNase during CTL-mediated apoptosis, and the nucleosome assembly protein SET is its inhibitor. Cell 112: 659-672, 2003. Note: Erratum: Cell 115: 241 only, 2003. [PubMed: 12628186] [Full Text: https://doi.org/10.1016/s0092-8674(03)00150-8]
Fan, Z., Beresford, P. J., Zhang, D., Xu, Z., Novina, C. D., Yoshida, A., Pommier, Y., Lieberman, J. Cleaving the oxidative repair protein Ape I enhances cell death mediated by granzyme A. Nature Immun. 4: 145-153, 2003. [PubMed: 12524539] [Full Text: https://doi.org/10.1038/ni885]
Fink, T. M., Lichter, P., Wekerle, H., Zimmer, M., Jenne, D. E. The human granzyme A (HFSP, CTLA3) gene maps to 5q11-q12 and defines a new locus of the serine protease superfamily. Genomics 18: 401-403, 1993. [PubMed: 8288245] [Full Text: https://doi.org/10.1006/geno.1993.1483]
Gershenfeld, H. K., Hershberger, R. J., Shows, T. B., Weissman, I. L. Cloning and chromosomal assignment of a human cDNA encoding a T cell- and natural killer cell-specific trypsin-like serine protease. Proc. Nat. Acad. Sci. 85: 1184-1188, 1988. [PubMed: 3257574] [Full Text: https://doi.org/10.1073/pnas.85.4.1184]
Gershenfeld, H. K., Weissman, I. L. Cloning of a cDNA for a T cell-specific serine protease from a cytotoxic T lymphocyte. Science 232: 854-858, 1986. [PubMed: 2422755] [Full Text: https://doi.org/10.1126/science.2422755]
Held, W., MacDonald, H. R., Weissman, I. L., Hess, M. W., Mueller, C. Genes encoding tumor necrosis factor alpha and granzyme A are expressed during development of autoimmune diabetes. Proc. Nat. Acad. Sci. 87: 2239-2243, 1990. [PubMed: 2179951] [Full Text: https://doi.org/10.1073/pnas.87.6.2239]
Justice, M. J., Silan, C. M., Ceci, J. D., Buchberg, A. M., Copeland, N. G., Jenkins, N. A. A molecular genetic linkage map of mouse chromosome 13 anchored by the beige (bg) and satin (sa) loci. Genomics 6: 341-351, 1990. [PubMed: 2307475] [Full Text: https://doi.org/10.1016/0888-7543(90)90575-f]
Martinvalet, D., Dykxhoorn, D. M., Ferrini, R., Lieberman, J. Granzyme A cleaves a mitochondrial complex I protein to initiate caspase-independent cell death. Cell 133: 681-692, 2008. [PubMed: 18485875] [Full Text: https://doi.org/10.1016/j.cell.2008.03.032]
Masson, D., Tschopp, J. A family of serine esterases in lytic granules of cytolytic T lymphocytes. Cell 49: 679-685, 1987. [PubMed: 3555842] [Full Text: https://doi.org/10.1016/0092-8674(87)90544-7]
Zhou, Z., He, H., Wang, K., Shi, X., Wang, Y., Su, Y., Wang, Y., Li, D., Liu, W., Zhang, Y., Shen, L., Han, W., Shen, L., Ding, J., Shao, F. Granzyme A from cytotoxic lymphocytes cleaves GSDMB to trigger pyroptosis in target cells. Science 368: eaaz7548, 2020. Note: Electronic Article. [PubMed: 32299851] [Full Text: https://doi.org/10.1126/science.aaz7548]