Disease relevance of GZMM

• We developed an in vivo model of ATL in non-obese diabetic/severe combined immunodeficient (NOD/ SCID) mice by introducing cells from an ATL patient (MET-1) into the mice [1].
• This study describes the genetic analysis of a series of skin squamous cell carcinomas, representing the primary tumor, two recurrences, and a metastatic lesion from a single patient and cell lines established therefrom (MET-1 to MET-4) [2].
• Novel carbapenem-hydrolyzing beta-lactamase (newly named MET-1) encoded on a transferable plasmid pMS390 from Shigella flexneri JS19622 was purified [3].

High impact information on GZMM

• The structure of the extra piece is as follows: Met-Pro-Gly-Ser-Arg-Thr-Ser-Leu-Leu-Ala-Phe-Ala-Leu-Leu-Cys-Leu-Pro-Trp-Leu-Gln-Glu-Ala-Gly-Ala-. Met1 is the initiator residue because only initiator [35S]Met-tRNAMet1, but not internal [35S]Met-tRNA2Met, donated NH2-terminal methionine [4].
• The ATL model was established by i.p. injection of human ATL cells (MET-1) into SCID/NOD wild-type or SCID/NOD FcRgamma-/- mice [5].
• In accord with this view, the MET-1 cells obtained from the spleens of leukemic mice did not produce IL-2, nor did they express IL-2 mRNA as assessed by reverse transcription-PCR [1].
• The MET-1 leukemic cells could be monitored by measurements of both serum soluble Tac (IL-2Ralpha) and soluble human beta2-microglobulin (beta2mu) by ELISA [1].
• The gene for the Hu-Met-1 serine protease is located on chromosome 19, which distinguishes it from any other member of the human granzyme family [6].

Biological context of GZMM

• The human Met-ase gene (GZMM): structure, sequence, and close physical linkage to the serine protease gene cluster on 19p13.3 [7].
• Using cosmid DNA as a probe for fluorescence in situ hybridization, we identified the chromosomal position of human Met-ase as 19p13 [7].
• The future creation of other granzyme gene knockout mice should elucidate whether other chymotrypsin-like granzymes (C-H) also contribute to target cell apoptosis and whether the third subfamily member, natural killer cell-specific Metase, has a distinct biological function [8].
• These subfamilies are most strikingly depicted by their distinct chromosomal loci and gene organization, dividing the granzyme family into subfamilies of the following: tryptases (human chromosome 5); chymotrypsin-like proteases (human chromosome 14); and a Metase amongst a cluster of elastase-like proteases (human chromosome 19) [8].
• Two METEX cDNA clones (Met1 and Met2) that are different in the 3' end have been isolated in a cDNA library screening [9].

Anatomical context of GZMM

• In Northern blot analysis human Met-ase (Hu-Met-1) cDNA hybridized with a 0.9-kb mRNA in two human NK leukemia cell lines, unstimulated human PBMC, and untreated purified CD3-CD56+ large granular lymphocytes [6].
• Met-ase: cloning and distinct chromosomal location of a serine protease preferentially expressed in human natural killer cells [6].
• The presence of Hu-Met-1 mRNA closely correlated with the Met-ase activity of cellular lysates prepared from these various human peripheral blood subsets and in vitro cultured cell lines [6].
• Met-ase activity detected in whole cell lysates of cytotoxic lymphocytes was associated with the cytoplasmic granules of these cells [6].
• PURPOSE: The objective of this study was to elucidate the different mechanisms of action of different excipients on the oxidation of Met1, Met122, Met127, and Met138 in granulocyte colony-stimulating factor (G-CSF) by using hydrogen peroxide as the oxidant [10].

Associations of GZMM with chemical compounds

• With granzymes, the compounds reacted with a fraction of the Met-ase, chymase, and Ser-ase activities and lacked reactivity with Asp-ase and tryptase [11].
• These kinetic studies establish that Met1, Met226, Met242, Met351, and Met358 are reactive with hydrogen peroxide at neutral pH and that each reactive methionine is oxidized in a bimolecular, rather than coupled, mechanism [12].
• The efficacy of EDTA on the rates of oxidation of the four methionine residues in G-CSF follows the order Met122 > Met127 > Met138 > Met1 [10].
• The H2O2-induced oxidation rate constants for free methionine, acetylcysteine, and glutathione at pH 4.5 were measured to be 32.07, 1.00, and 1.63 M(-1)h(-1), respectively, while the oxidation rate constant for Met1, the most readily oxidizable methionine residue in G-CSF, is 13.95 M(-1)h(-1) [13].
• Furthermore, model peptides without disulfide bond(s) could not assume a stable structure in aqueous solution, while they did have similar alpha-helical content in 50% trifluoroethanol with MET-1 [14].

Other interactions of GZMM

• We also addressed the functional integrity of these cultured cells by examining the appearance of granzyme A, serine esterase, Met-ase and perforin and correlating these with lytic activity [15].

Analytical, diagnostic and therapeutic context of GZMM

• METHODS: The oxidation of Met1, Met127, and Met138 was quantified by peptide mapping analysis [10].
• The molecular weight was determined as 26,000-28,000 by gel filtration, 30,850 +/- 1500 by sedimentation analysis and 26,930-27,410 by calculation from the amino acid composition (Lys20-21, His3, Arg9, Asp21-22, Thr13, Ser18, Pro12-13, Glu23-24, Gly30, Ala16, Cys/29, Val19, Met1, Ile10, Leu13, Tyr14, Phe6, Trp3) [16].

References