1
|
Valentini P, Akula S, Alvarado-Vazquez A, Hallgren J, Fu Z, Racicot B, Braasch I, Thorpe M, Hellman L. Extended Cleavage Specificity of two Hematopoietic Serine Proteases from a Ray-Finned Fish, the Spotted Gar ( Lepisosteus oculatus). Int J Mol Sci 2024; 25:1669. [PMID: 38338947 PMCID: PMC10855939 DOI: 10.3390/ijms25031669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/12/2024] Open
Abstract
The extended cleavage specificities of two hematopoietic serine proteases originating from the ray-finned fish, the spotted gar (Lepisosteus oculatus), have been characterized using substrate phage display. The preference for particular amino acids at and surrounding the cleavage site was further validated using a panel of recombinant substrates. For one of the enzymes, the gar granzyme G, a strict preference for the aromatic amino acid Tyr was observed at the cleavable P1 position. Using a set of recombinant substrates showed that the gar granzyme G had a high selectivity for Tyr but a lower activity for cleaving after Phe but not after Trp. Instead, the second enzyme, gar DDN1, showed a high preference for Leu in the P1 position of substrates. This latter enzyme also showed a high preference for Pro in the P2 position and Arg in both P4 and P5 positions. The selectivity for the two Arg residues in positions P4 and P5 suggests a highly specific substrate selectivity of this enzyme. The screening of the gar proteome with the consensus sequences obtained by substrate phage display for these two proteases resulted in a very diverse set of potential targets. Due to this diversity, a clear candidate for a specific immune function of these two enzymes cannot yet be identified. Antisera developed against the recombinant gar enzymes were used to study their tissue distribution. Tissue sections from juvenile fish showed the expression of both proteases in cells in Peyer's patch-like structures in the intestinal region, indicating they may be expressed in T or NK cells. However, due to the lack of antibodies to specific surface markers in the gar, it has not been possible to specify the exact cellular origin. A marked difference in abundance was observed for the two proteases where gar DDN1 was expressed at higher levels than gar granzyme G. However, both appear to be expressed in the same or similar cells, having a lymphocyte-like appearance.
Collapse
Affiliation(s)
- Paolo Valentini
- Department of Cell and Molecular Biology, Uppsala University, P.O. Box 596, SE-751 24 Uppsala, Sweden; (P.V.); (S.A.); (Z.F.); (M.T.)
| | - Srinivas Akula
- Department of Cell and Molecular Biology, Uppsala University, P.O. Box 596, SE-751 24 Uppsala, Sweden; (P.V.); (S.A.); (Z.F.); (M.T.)
| | - Abigail Alvarado-Vazquez
- Department of Medical Biochemistry and Microbiology, Uppsala University Biomedical Centre (BMC), P.O. Box 582, SE-751 23 Uppsala, Sweden; (A.A.-V.); (J.H.)
| | - Jenny Hallgren
- Department of Medical Biochemistry and Microbiology, Uppsala University Biomedical Centre (BMC), P.O. Box 582, SE-751 23 Uppsala, Sweden; (A.A.-V.); (J.H.)
| | - Zhirong Fu
- Department of Cell and Molecular Biology, Uppsala University, P.O. Box 596, SE-751 24 Uppsala, Sweden; (P.V.); (S.A.); (Z.F.); (M.T.)
| | - Brett Racicot
- Department of Integrative Biology, Michigan State University, East Lansing, MI 48825, USA; (B.R.); (I.B.)
| | - Ingo Braasch
- Department of Integrative Biology, Michigan State University, East Lansing, MI 48825, USA; (B.R.); (I.B.)
- Ecology, Evolution and Behavior Program, Michigan State University, East Lansing, MI 48825, USA
| | - Michael Thorpe
- Department of Cell and Molecular Biology, Uppsala University, P.O. Box 596, SE-751 24 Uppsala, Sweden; (P.V.); (S.A.); (Z.F.); (M.T.)
| | - Lars Hellman
- Department of Cell and Molecular Biology, Uppsala University, P.O. Box 596, SE-751 24 Uppsala, Sweden; (P.V.); (S.A.); (Z.F.); (M.T.)
| |
Collapse
|
2
|
Thorpe M, Akula S, Fu Z, Hellman L. The Extended Cleavage Specificity of Channel Catfish Granzyme-like II, A Highly Specific Elastase, Expressed by Natural Killer-like Cells. Int J Mol Sci 2023; 25:356. [PMID: 38203526 PMCID: PMC10778636 DOI: 10.3390/ijms25010356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/20/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024] Open
Abstract
The extended cleavage specificity of catfish granzyme-like II has been characterized using substrate phage display. The preference for particular amino acids at and surrounding the cleavage site was further validated by using a panel of recombinant substrates. This serine protease, which has previously been isolated as cDNA from a catfish natural killer-like cell line showed a preference for Ala in the P1 position of the substrate, and for multiple basic amino acids N-terminally of the cleavage site. A closely related zebrafish serine protease (zebrafish esterase-like) showed a very similar cleavage specificity, indicating an evolutionary conservation of this protease specificity among various fish species. Two catfish serine proteases, originating from NK-like cells, have now been isolated and characterized. One of them is highly specific met-ase with similar characteristics as the mammalian granzyme M. This enzyme may be involved in the induction of apoptosis in virus-infected cells, with a potential target in (catfish) caspase 6. In contrast to catfish granzyme-like I, the second enzyme analyzed here does not seem to have a direct counterpart in mammalian NK cells, and its role in the immune function of catfish NK cells is, therefore, still not known. However, this enzyme seems to be able to cleave a number of cytoskeletal proteins, indicating a separate strategy to induce apoptosis in target cells. Both of these enzymes are very interesting targets for further studies of their roles in catfish immunity, as enzymes with similar specificities have also been identified in zebrafish.
Collapse
Affiliation(s)
| | | | | | - Lars Hellman
- Department of Cell and Molecular Biology, Uppsala University, Box 596, SE-751 24 Uppsala, Sweden; (M.T.); (S.A.); (Z.F.)
| |
Collapse
|