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Okawa K, Tabata E, Kida Y, Uno K, Suzuki H, Kamaya M, Bauer PO, Oyama F. Irreversible evolutionary loss of chitin-degrading ability in the chitinase-like protein Ym1 under positive selection in rodents. Protein Sci 2023; 32:e4620. [PMID: 36883357 PMCID: PMC10031810 DOI: 10.1002/pro.4620] [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: 10/28/2022] [Revised: 02/27/2023] [Accepted: 03/02/2023] [Indexed: 03/09/2023]
Abstract
Ym1 (chitinase-like 3, Chil3) expressed in mice is a nonenzymatic chitinase-like protein, which shows 67% identity with mouse acidic chitinase (Chia). Similar to Chia, Ym1 is overexpressed in asthma and parasitic infections in mouse lungs. Due to the lack of chitin-degrading activity, the biomedical role of Ym1 under these pathophysiological conditions remains to be determined. In this study, we investigated what region and amino acid changes in Ym1 resulted in the loss of enzymatic activity. Replacing two amino acids at the catalytic motif to obtain a Chia-like sequence (N136D and Q140E; MT-Ym1) did not activate the protein. We conducted a comparative study of Ym1 and Chia. We found that three protein segments-(i) the catalytic motif residues, (ii) exons 6 and 7, and (iii) exon 10-are responsible for chitinase activity loss in Ym1. We show that replacing each of these three segments in Chia that are also involved in substrate recognition and binding by the Ym1 sequence can fully abolish the enzymatic activity. In addition, we show that there have been extensive gene duplication events at the Ym1 locus specific to the rodent lineages. Consistent with this result, Ym1 orthologs from the rodent genome were under positive selection when analyzed through the CODEML program. These data suggest that numerous amino acid substitutions in the regions involved in the chitin recognition, binding, and degradation ability of the ancestor Ym1 molecule lead to the irreversible inactivation of the protein.
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Affiliation(s)
- Kazuaki Okawa
- Department of Chemistry and Life ScienceKogakuin UniversityTokyoJapan
| | - Eri Tabata
- Department of Chemistry and Life ScienceKogakuin UniversityTokyoJapan
- Japan Society for the Promotion of Science (PD)TokyoJapan
| | - Yuta Kida
- Department of Chemistry and Life ScienceKogakuin UniversityTokyoJapan
| | - Kyohei Uno
- Department of Chemistry and Life ScienceKogakuin UniversityTokyoJapan
| | - Hidetoshi Suzuki
- Department of Chemistry and Life ScienceKogakuin UniversityTokyoJapan
| | - Minori Kamaya
- Department of Applied ChemistryKogakuin UniversityTokyoJapan
| | | | - Fumitaka Oyama
- Department of Chemistry and Life ScienceKogakuin UniversityTokyoJapan
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Kang Q, Li L, Pang Y, Zhu W, Meng L. An update on Ym1 and its immunoregulatory role in diseases. Front Immunol 2022; 13:891220. [PMID: 35967383 PMCID: PMC9366555 DOI: 10.3389/fimmu.2022.891220] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 07/06/2022] [Indexed: 11/23/2022] Open
Abstract
Ym1 is a rodent-specific chitinase-like protein (CLP) lacking catalytic activity, whose cellular origins are mainly macrophages, neutrophils and other cells. Although the detailed function of Ym1 remains poorly understood, Ym1 has been generally recognized as a fundamental feature of alternative activation of macrophages in mice and hence one of the prevalent detecting targets in macrophage phenotype distinguishment. Studies have pointed out that Ym1 may have regulatory effects, which are multifaceted and even contradictory, far more than just a mere marker. Allergic lung inflammation, parasite infection, autoimmune diseases, and central nervous system diseases have been found associations with Ym1 to varying degrees. Thus, insights into Ym1’s role in diseases would help us understand the pathogenesis of different diseases and clarify the genuine roles of CLPs in mammals. This review summarizes the information on Ym1 from the gene to its expression and regulation and focuses on the association between Ym1 and diseases.
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Affiliation(s)
- Qi Kang
- Institute of Molecular and Translational Medicine, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, China
- Department of Clinical Medicine, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Luyao Li
- Institute of Molecular and Translational Medicine, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, China
- Department of Clinical Medicine, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Yucheng Pang
- Institute of Molecular and Translational Medicine, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, China
- Department of Clinical Medicine, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Wenhua Zhu
- Institute of Molecular and Translational Medicine, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, China
- *Correspondence: Wenhua Zhu, ; Liesu Meng,
| | - Liesu Meng
- Institute of Molecular and Translational Medicine, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
- Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, China
- National Joint Engineering Research Center of Biodiagnostics and Biotherapy, Second Affiliated Hospital, Xi’an Jiaotong University, Xi’an, China
- *Correspondence: Wenhua Zhu, ; Liesu Meng,
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Therajaran P, Hamilton JA, O'Brien TJ, Jones NC, Ali I. Microglial polarization in posttraumatic epilepsy: Potential mechanism and treatment opportunity. Epilepsia 2020; 61:203-215. [PMID: 31943156 DOI: 10.1111/epi.16424] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/17/2022]
Abstract
Owing to the complexity of the pathophysiological mechanisms driving epileptogenesis following traumatic brain injury (TBI), effective preventive treatment approaches are not yet available for posttraumatic epilepsy (PTE). Neuroinflammation appears to play a critical role in the pathogenesis of the acquired epilepsies, including PTE, but despite a large preclinical literature demonstrating the ability of anti-inflammatory treatments to suppress epileptogenesis and chronic seizures, no anti-inflammatory treatment approaches have been clinically proven to date. TBI triggers robust inflammatory cascades, suggesting that they may be relevant for the pathogenesis of PTE. A major cell type involved in such cascades is the microglial cells-brain-resident immune cells that become activated after brain injury. When activated, these cells can oscillate between different phenotypes, and such polarization states are associated with the release of various pro- and anti-inflammatory mediators that may influence brain repair processes, and also differentially contribute to the development of PTE. As the molecular mechanisms and key signaling molecules associated with microglial polarization in brain are discovered, strategies are now emerging that can modulate this polarization, promoting this as a potential therapeutic strategy for PTE. In this review, we discuss the relevant literature regarding the polarization of brain-resident immune cells following TBI and attempt to put into perspective a role in epilepsy pathogenesis. Finally, we explore potential strategies that could polarize microglia/macrophages toward a neuroprotective phenotype to mitigate PTE development.
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Affiliation(s)
- Peravina Therajaran
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
| | - John A Hamilton
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Terence J O'Brien
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia.,Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia.,Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia
| | - Nigel C Jones
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia.,Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia.,Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia
| | - Idrish Ali
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia.,Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia.,Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia
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4
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Quarta A, Le Blon D, D'aes T, Pieters Z, Hamzei Taj S, Miró-Mur F, Luyckx E, Van Breedam E, Daans J, Goossens H, Dewilde S, Hens N, Pasque V, Planas AM, Hoehn M, Berneman Z, Ponsaerts P. Murine iPSC-derived microglia and macrophage cell culture models recapitulate distinct phenotypical and functional properties of classical and alternative neuro-immune polarisation. Brain Behav Immun 2019; 82:406-421. [PMID: 31525508 DOI: 10.1016/j.bbi.2019.09.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/05/2019] [Accepted: 09/12/2019] [Indexed: 12/24/2022] Open
Abstract
The establishment and validation of reliable induced pluripotent stem cell (iPSC)-derived in vitro models to study microglia and monocyte/macrophage immune function holds great potential for fundamental and translational neuro-immunology research. In this study, we first demonstrate that ramified CX3CR1+ iPSC-microglia (cultured within a neural environment) and round-shaped CX3CR1- iPSC-macrophages can easily be differentiated from newly established murine CX3CR1eGFP/+CCR2RFP/+ iPSC lines. Furthermore, we show that obtained murine iPSC-microglia and iPSC-macrophages are distinct cell populations, even though iPSC-macrophages may upregulate CX3CR1 expression when cultured within a neural environment. Next, we characterized the phenotypical and functional properties of murine iPSC-microglia and iPSC-macrophages following classical and alternative immune polarisation. While iPSC-macrophages could easily be triggered to adopt a classically-activated or alternatively-activated phenotype following, respectively, lipopolysaccharide + interferon γ or interleukin 13 (IL13) stimulation, iPSC-microglia and iPSC-macrophages cultured within a neural environment displayed a more moderate activation profile as characterised by the absence of MHCII expression upon classical immune polarisation and the absence of Ym1 expression upon alternative immune polarisation. Finally, extending our preceding in vivo studies, this striking phenotypical divergence was also observed for resident microglia and infiltrating monocytes within highly inflammatory cortical lesions in CX3CR1eGFP/+CCR2RFP/+ mice subjected to middle cerebral arterial occlusion (MCAO) stroke and following IL13-mediated therapeutic intervention thereon. In conclusion, our study demonstrates that the applied murine iPSC-microglia and iPSC-macrophage culture models are able to recapitulate in vivo microglia and monocyte/macrophage ontogeny and corresponding phenotypical/functional properties upon classical and alternative immune polarisation, and therefore represent a valuable in vitro platform to further study and modulate microglia and (infiltrating) monocyte immune responses under neuro-inflammatory conditions within a neural environment.
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Affiliation(s)
- Alessandra Quarta
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Debbie Le Blon
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Tine D'aes
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Zoë Pieters
- Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium; Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Belgium; Centre for Health Economics Research and Modelling Infectious Diseases, University of Antwerp, Belgium
| | - Somayyeh Hamzei Taj
- In-vivo-NMR Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Francesc Miró-Mur
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Evi Luyckx
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium; Protein Chemistry, Proteomics and Epigenetic Signaling, University of Antwerp, Antwerp, Belgium
| | - Elise Van Breedam
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Jasmijn Daans
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Herman Goossens
- Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Sylvia Dewilde
- Protein Chemistry, Proteomics and Epigenetic Signaling, University of Antwerp, Antwerp, Belgium
| | - Niel Hens
- Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium; Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Hasselt University, Belgium; Centre for Health Economics Research and Modelling Infectious Diseases, University of Antwerp, Belgium
| | - Vincent Pasque
- Department of Development and Regeneration, Leuven Stem Cell Institute, Leuven Cancer Institute, KU Leuven - University of Leuven, Belgium
| | - Anna M Planas
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Department of Brain Ischemia and Neurodegeneration, Institut d'Investigacions Biomèdiques de Barcelona (IIBB)-Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Mathias Hoehn
- In-vivo-NMR Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany; Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Zwi Berneman
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium
| | - Peter Ponsaerts
- Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium; Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Antwerp, Belgium.
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Collmann FM, Pijnenburg R, Hamzei-Taj S, Minassian A, Folz-Donahue K, Kukat C, Aswendt M, Hoehn M. Individual in vivo Profiles of Microglia Polarization After Stroke, Represented by the Genes iNOS and Ym1. Front Immunol 2019; 10:1236. [PMID: 31214190 PMCID: PMC6558167 DOI: 10.3389/fimmu.2019.01236] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 05/15/2019] [Indexed: 12/26/2022] Open
Abstract
Microglia are the brain-innate immune cells which actively surveil their environment and mediate multiple aspects of neuroinflammation, due to their ability to acquire diverse activation states and phenotypes. Simplified, M1-like microglia are defined as pro-inflammatory cells, while the alternative M2-like cells promote neuroprotection. The modulation of microglia polarization is an appealing neurotherapeutic strategy for stroke and other brain lesions, as well as neurodegenerative diseases. However, the activation profile and change of phenotype during experimental stroke is not well understood. With a combined magnetic resonance imaging (MRI) and optical imaging approach and genetic targeting of two key genes of the M1- and M2-like phenotypes, iNOS and Ym1, we were able to monitor in vivo the dynamic adaption of the microglia phenotype in response to experimental stroke.
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Affiliation(s)
- Franziska M Collmann
- In-vivo-NMR, Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Rory Pijnenburg
- In-vivo-NMR, Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Somayyeh Hamzei-Taj
- In-vivo-NMR, Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Anuka Minassian
- In-vivo-NMR, Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Kat Folz-Donahue
- FACS & Imaging Core Facility, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Christian Kukat
- FACS & Imaging Core Facility, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Markus Aswendt
- In-vivo-NMR, Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany.,Department of Neurology, University Hospital Cologne, Cologne, Germany
| | - Mathias Hoehn
- In-vivo-NMR, Laboratory, Max Planck Institute for Metabolism Research, Cologne, Germany.,Radiology Department, Leiden University Medical Center, Leiden, Netherlands.,PERCUROS, Enschede, Netherlands
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Donnelly S, Stack CM, O'Neill SM, Sayed AA, Williams DL, Dalton JP. Helminth 2-Cys peroxiredoxin drives Th2 responses through a mechanism involving alternatively activated macrophages. FASEB J 2008; 22:4022-32. [PMID: 18708590 DOI: 10.1096/fj.08-106278] [Citation(s) in RCA: 186] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
During helminth infections, alternatively activated macrophages (AAMacs) are key to promoting Th2 responses and suppressing Th1-driven inflammatory pathology. Th2 cytokines IL-4 and/or IL-13 are believed to be important in the induction and activation of AAMacs. Using murine models for the helminth infections caused by Fasciola hepatica (Fh) and Schistosoma mansoni (Sm), we show that a secreted antioxidant, peroxiredoxin (Prx), induces alternative activation of macrophages. These activated, Ym1-expressing macrophages enhanced the secretion of IL-4, IL-5, and IL-13 from naive CD4(+) T cells. Administration of recombinant FhPrx and SmPrx to wild-type and IL-4(-/-) and IL-13(-/-) mice induced the production of AAMacs. In addition, Prx stimulated the expression of markers of AAMacs (particularly, Ym1) in vitro, and therefore can act independently of IL-4/IL-13 signaling. The immunomodulatory property of Prx is not due to its antioxidant activity, as an inactive recombinant variant with active site Cys residues replaced by Gly could also induce AAMacs and Th2 responses. Immunization of mice with recombinant Prx or passive transfer of anti-Prx antibodies prior to infection with Fh not only blocked the induction of AAMacs but also the development of parasite-specific Th2 responses. We propose that Prx activates macrophages as an initial step in the induction of Th2 responses by helminth parasites and is thereby a novel pathogen-associated molecular pattern.
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Affiliation(s)
- Sheila Donnelly
- Level 6, Bldg. 4, University of Technology Sydney, Cnr. Thomas and Harris St., Ultimo, Sydney, NSW 2007, Australia
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Lee E, Yook J, Haa K, Chang HW. Induction of Ym1/2 in mouse bone marrow-derived mast cells by IL-4 and identification of Ym1/2 in connective tissue type-like mast cells derived from bone marrow cells cultured with IL-4 and stem cell factor. Immunol Cell Biol 2008; 83:468-74. [PMID: 16174095 DOI: 10.1111/j.1440-1711.2005.01352.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mast cells play an important role in allergic inflammation by releasing various bioactive mediators. The function of mast cells is enhanced by various stimuli, partly due to the induction of specific genes and their products. Although many inducible genes have been identified, a significant number of genes remain to be identified. Therefore, this study used PCR-selected cDNA subtraction to establish the profile of induced genes in the connective tissue (CT) type-like mast cells derived from bone marrow cells cultured in the presence of IL-4 and stem cell factor. Two hundred and fifty cDNA clones were obtained from the CT type-like mast cells by PCR-selected cDNA subtraction. Among them, Ym1/2, a chitinase-like protein, is one of the most abundantly induced genes. Ym1 is produced by activated macrophages in a parasitic infection, whereas its isotype, Ym2, is highly upregulated in allergic lung disease. In order to differentiate which isotype is expressed in bone marrow cells, specific primers for bone marrow-derived mast cells (BMMC), and CT type-like mast cells were used for RT-PCR. The results showed that Ym1 was constitutively expressed in bone marrow cells and gradually decreased in the presence of IL-3, whereas Ym2 was induced only in the presence of IL-4. CT type-like mast cells from bone marrow cells expressed Ym1 throughout the culture period and Ym2 was induced only by the addition of IL-4 into BMMC, indicating that IL-4 is essential for the expression of Ym1/2 genes.
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Affiliation(s)
- Eunkyung Lee
- College of Pharmacy, Yeungnam University, Gyeongsan, Korea
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Shi L, Paskewitz SM. Identification and molecular characterization of two immune-responsive chitinase-like proteins from Anopheles gambiae. INSECT MOLECULAR BIOLOGY 2004; 13:387-398. [PMID: 15271211 DOI: 10.1111/j.0962-1075.2004.00496.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Two haemolymph proteins that are processed rapidly and specifically in response to exposure to bacteria have been identified from Anopheles gambiae. Both proteins, Anopheles gambiae bacteria-responsive 1 (AgBR1) and AgBR2, are similar to chitinases but belong to a family of proteins that have lost chitinolytic activity. AgBR1 and AgBR2 are converted to smaller forms in vivo or in vitro on exposure to bacteria, and AgBR2 also can be processed on exposure to peptidoglycan alone. AgBR1 and AgBR2 do not bind to bacteria or chitin beads. The AgBR1 and AgBR2 genes are expressed in all developmental stages. In adults, AgBR1 expression is restricted to the fat body, whereas AgBR2 is expressed in many tissues.
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Affiliation(s)
- L Shi
- Department of Entomology, University of Wisconsin, Madison, WI, USA
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