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Yang S, Min X, Hu L, Zheng M, Lu S, Zhao M, Jia S. RFX1 regulates foam cell formation and atherosclerosis by mediating CD36 expression. Int Immunopharmacol 2024; 130:111751. [PMID: 38402833 DOI: 10.1016/j.intimp.2024.111751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 02/06/2024] [Accepted: 02/21/2024] [Indexed: 02/27/2024]
Abstract
BACKGROUND AND AIMS Atherosclerosis (AS) is a continuously low-grade inflammatory disease, and monocyte-derived macrophages play a vital role in AS pathogenesis. Regulatory factor X1 (RFX1) has been reported to participate in differentiation of various cells. Our previous report showed that RFX1 expression in CD14+ monocytes from AS patients was decreased and closely related to AS development. Macrophages mostly derive from monocytes and play an important role in AS plaque formation and stability. However, the functions of RFX1 in the formation of macrophage-derived foam cells and consequent AS development are unclear. METHODS We explored the effects of RFX1 on oxidation low lipoprotein (ox-LDL)-stimulated foam cell formation and CD36 expression by increasing or silencing Rfx1 expression in mouse peritoneal macrophages (PMAs). The ApoE-/-Rfx1f/f or ApoE-/-Rfx1f/f Lyz2-Cre mice fed a high-fat diet for 24 weeks were used to further examine the effect of RFX1 on AS pathogenesis. We then performed dual luciferase reporter assays to study the regulation of RFX1 for CD36 transcription. RESULTS Our results demonstrate that RFX1 expression was significantly reduced in ox-LDL induced foam cells and negatively correlated with lipid uptake in macrophages. Besides, Rfx1 deficiency in myeloid cells aggravated atherosclerotic lesions in ApoE-/- mice. Mechanistically, RFX1 inhibited CD36 expression by directly regulating CD36 transcription in macrophages. CONCLUSIONS The reduction of RFX1 expression in macrophages is a vital determinant for foam cell formation and the initiation of AS, proving a potential novel approach for the treatment of AS disease.
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Affiliation(s)
- Shuang Yang
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha 410011, China
| | - Xiaoli Min
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China; Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Chinese Academy of Medical Sciences, Nanjing, China
| | - Longyuan Hu
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha 410011, China
| | - Meiling Zheng
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha 410011, China
| | - Shuang Lu
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha 410011, China
| | - Ming Zhao
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha 410011, China; Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China; Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Chinese Academy of Medical Sciences, Nanjing, China
| | - Sujie Jia
- Department of Pharmacy, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China.
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Yang S, Du P, Cui H, Zheng M, He W, Gao X, Hu Z, Jia S, Lu Q, Zhao M. Regulatory factor X1 induces macrophage M1 polarization by promoting DNA demethylation in autoimmune inflammation. JCI Insight 2023; 8:e165546. [PMID: 37733446 PMCID: PMC10619507 DOI: 10.1172/jci.insight.165546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 09/06/2023] [Indexed: 09/23/2023] Open
Abstract
Abnormal macrophage polarization is generally present in autoimmune diseases. Overwhelming M1 macrophage activation promotes the continuous progression of inflammation, which is one of the reasons for the development of autoimmune diseases. However, the underlying mechanism is still unclear. Here we explore the function of Regulatory factor X1 (RFX1) in macrophage polarization by constructing colitis and lupus-like mouse models. Both in vivo and in vitro experiments confirmed that RFX1 can promote M1 and inhibit M2 macrophage polarization. Furthermore, we found that RFX1 promoted DNA demethylation of macrophage polarization-related genes by increasing APOBEC3A/Apobec3 expression. We identified a potential RFX1 inhibitor, adenosine diphosphate (ADP), providing a potential strategy for treating autoimmune diseases.
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Affiliation(s)
- Shuang Yang
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, China
- Research Unit of Key Technologies of Diagnosis and Treatment for Immune-related Skin Diseases, Chinese Academy of Medical Sciences, Central South University, Changsha, China
| | - Pei Du
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, China
- Research Unit of Key Technologies of Diagnosis and Treatment for Immune-related Skin Diseases, Chinese Academy of Medical Sciences, Central South University, Changsha, China
| | - Haobo Cui
- Department of Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Meiling Zheng
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, China
- Research Unit of Key Technologies of Diagnosis and Treatment for Immune-related Skin Diseases, Chinese Academy of Medical Sciences, Central South University, Changsha, China
| | - Wei He
- Department of Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Xiaofei Gao
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, China
- Research Unit of Key Technologies of Diagnosis and Treatment for Immune-related Skin Diseases, Chinese Academy of Medical Sciences, Central South University, Changsha, China
| | - Zhi Hu
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, China
- Research Unit of Key Technologies of Diagnosis and Treatment for Immune-related Skin Diseases, Chinese Academy of Medical Sciences, Central South University, Changsha, China
| | - Sujie Jia
- Department of Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Qianjin Lu
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
- Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Chinese Academy of Medical Sciences, Nanjing, China
| | - Ming Zhao
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, China
- Research Unit of Key Technologies of Diagnosis and Treatment for Immune-related Skin Diseases, Chinese Academy of Medical Sciences, Central South University, Changsha, China
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
- Key Laboratory of Basic and Translational Research on Immune-Mediated Skin Diseases, Chinese Academy of Medical Sciences, Nanjing, China
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Issac J, Raveendran PS, Kunnummal M, Angelin M, Ravindran S, Basu B, Das AV. RXR agonist, Bexarotene, effectively reduces drug resistance via regulation of RFX1 in embryonic carcinoma cells. Biochim Biophys Acta Mol Cell Res 2023; 1870:119510. [PMID: 37301270 DOI: 10.1016/j.bbamcr.2023.119510] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/16/2023] [Accepted: 06/02/2023] [Indexed: 06/12/2023]
Abstract
Aberrant expression of multidrug resistance (MDR) proteins is one of the features of cancer stem cells (CSCs) that make them escape chemotherapy. A well-orchestrated regulation of multiple MDRs by different transcription factors in cancer cells confers this drug resistance. An in silico analysis of the major MDR genes revealed a possible regulation by RFX1 and Nrf2. Previous reports also noted that Nrf2 is a positive regulator of MDR genes in NT2 cells. But we, for the first time, report that Regulatory factor X1 (RFX1), a pleiotropic transcription factor, negatively regulates the major MDR genes, Abcg2, Abcb1, Abcc1, and Abcc2, in NT2 cells. The levels of RFX1 in undifferentiated NT2 cells were found to be very low, which significantly increased upon RA-induced differentiation. Ectopic expression of RFX1 reduced the levels of transcripts corresponding to MDRs and stemness-associated genes. Interestingly, Bexarotene, an RXR agonist that acts as an inhibitor of Nrf2-ARE signaling, could increase the transcription of RFX1. Further analysis revealed that the RFX1 promoter has binding sites for RXRα, and upon Bexarotene exposure RXRα could bind and activate the RFX1 promoter. Bexarotene, alone or in combination with Cisplatin, could inhibit many cancer/CSC-associated properties in NT2 cells. Also, it significantly reduced the expression of drug resistance proteins and made the cells sensitive towards Cisplatin. Our study proves that RFX1 could be a potent molecule to target MDRs, and Bexarotene can induce RXRα-mediated RFX1 expression, therefore, would be a better chemo-assisting drug during therapy.
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Affiliation(s)
- Joby Issac
- Cancer Research Program-12, Rajiv Gandhi Centre for Biotechnology (DBT-RGCB), Thycaud. P.O. Thiruvananthapuram-14, Kerala, India
| | - Pooja S Raveendran
- Cancer Research Program-12, Rajiv Gandhi Centre for Biotechnology (DBT-RGCB), Thycaud. P.O. Thiruvananthapuram-14, Kerala, India; Manipal Academy of Higher Education, Tiger Circle Road, Madhav Nagar, Manipal, Karnataka 576104, India
| | - Midhunaraj Kunnummal
- Cancer Research Program-12, Rajiv Gandhi Centre for Biotechnology (DBT-RGCB), Thycaud. P.O. Thiruvananthapuram-14, Kerala, India; Manipal Academy of Higher Education, Tiger Circle Road, Madhav Nagar, Manipal, Karnataka 576104, India
| | - Mary Angelin
- Cancer Research Program-12, Rajiv Gandhi Centre for Biotechnology (DBT-RGCB), Thycaud. P.O. Thiruvananthapuram-14, Kerala, India
| | - Swathy Ravindran
- Cancer Research Program-12, Rajiv Gandhi Centre for Biotechnology (DBT-RGCB), Thycaud. P.O. Thiruvananthapuram-14, Kerala, India
| | - Budhaditya Basu
- Neuro Stem Cell Biology Laboratory, Neurobiology Division, Rajiv Gandhi Centre for Biotechnology (DBT-RGCB), Thiruvananthapuram, Kerala 695 014, India; Regional Centre for Biotechnology (DBT-RCB), Faridabad, Haryana 121001, India
| | - Ani V Das
- Cancer Research Program-12, Rajiv Gandhi Centre for Biotechnology (DBT-RGCB), Thycaud. P.O. Thiruvananthapuram-14, Kerala, India; Manipal Academy of Higher Education, Tiger Circle Road, Madhav Nagar, Manipal, Karnataka 576104, India.
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Mizukawa T, Nishida T, Akashi S, Kawata K, Kikuchi S, Kawaki H, Takigawa M, Kamioka H, Kubota S. RFX1-mediated CCN3 induction that may support chondrocyte survival under starved conditions. J Cell Physiol 2021; 236:6884-6896. [PMID: 33655492 DOI: 10.1002/jcp.30348] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 02/12/2021] [Accepted: 02/16/2021] [Indexed: 02/06/2023]
Abstract
Cellular communication network factor (CCN) family members are multifunctional matricellular proteins that manipulate and integrate extracellular signals. In our previous studies investigating the role of CCN family members in cellular metabolism, we found three members that might be under the regulation of energy metabolism. In this study, we confirmed that CCN2 and CCN3 are the only members that are tightly regulated by glycolysis in human chondrocytic cells. Interestingly, CCN3 was induced under a variety of impaired glycolytic conditions. This CCN3 induction was also observed in two breast cancer cell lines with a distinct phenotype, suggesting a basic role of CCN3 in cellular metabolism. Reporter gene assays indicated a transcriptional regulation mediated by an enhancer in the proximal promoter region. As a result of analyses in silico, we specified regulatory factor binding to the X-box 1 (RFX1) as a candidate that mediated the transcriptional activation by impaired glycolysis. Indeed, the inhibition of glycolysis induced the expression of RFX1, and RFX1 silencing nullified the CCN3 induction by impaired glycolysis. Subsequent experiments with an anti-CCN3 antibody indicated that CCN3 supported the survival of chondrocytes under impaired glycolysis. Consistent with these findings in vitro, abundant CCN3 production by chondrocytes in the deep zones of developing epiphysial cartilage, which are located far away from the synovial fluid, was confirmed in vivo. Our present study uncovered that RFX1 is the mediator that enables CCN3 induction upon cellular starvation, which may eventually assist chondrocytes in retaining their viability, even when there is an energy supply shortage.
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Affiliation(s)
- Tomomi Mizukawa
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Takashi Nishida
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Okayama, Japan
| | - Sho Akashi
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Department of Oral and Maxillofacial Reconstructive Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Kazumi Kawata
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Sumire Kikuchi
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Harumi Kawaki
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Department of Oral Biochemistry, Asahi University School of Dentistry, Mizuho, Japan
| | - Masaharu Takigawa
- Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Okayama, Japan
| | - Hiroshi Kamioka
- Department of Orthodontics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Satoshi Kubota
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
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Zhang Y, Zhang X, Dai Y, Song M, Zhou Y, Zhou J, Yan X, Shen Y. The decrease of intraflagellar transport impairs sensory perception and metabolism in ageing. Nat Commun 2021; 12:1789. [PMID: 33741976 PMCID: PMC7979750 DOI: 10.1038/s41467-021-22065-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 02/26/2021] [Indexed: 12/22/2022] Open
Abstract
Sensory perception and metabolic homeostasis are known to deteriorate with ageing, impairing the health of aged animals, while mechanisms underlying their deterioration remain poorly understood. The potential interplay between the declining sensory perception and the impaired metabolism during ageing is also barely explored. Here, we report that the intraflagellar transport (IFT) in the cilia of sensory neurons is impaired in the aged nematode Caenorhabditis elegans due to a daf-19/RFX-modulated decrease of IFT components. We find that the reduced IFT in sensory cilia thus impairs sensory perception with ageing. Moreover, we demonstrate that whereas the IFT-dependent decrease of sensory perception in aged worms has a mild impact on the insulin/IGF-1 signalling, it remarkably suppresses AMP-activated protein kinase (AMPK) signalling across tissues. We show that upregulating daf-19/RFX effectively enhances IFT, sensory perception, AMPK activity and autophagy, promoting metabolic homeostasis and longevity. Our study determines an ageing pathway causing IFT decay and sensory perception deterioration, which in turn disrupts metabolism and healthy ageing.
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Affiliation(s)
- Yincong Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiaona Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yumin Dai
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Mengjiao Song
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yifei Zhou
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jun Zhou
- Institute of Biomedical Sciences, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Collaborative Innovation Center of Cell Biology in Universities of Shandong, Shandong Normal University, Jinan, Shandong, China
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Xiumin Yan
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yidong Shen
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China.
- University of Chinese Academy of Sciences, Beijing, China.
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De Stasio EA, Mueller KP, Bauer RJ, Hurlburt AJ, Bice SA, Scholtz SL, Phirke P, Sugiaman-Trapman D, Stinson LA, Olson HB, Vogel SL, Ek-Vazquez Z, Esemen Y, Korzynski J, Wolfe K, Arbuckle BN, Zhang H, Lombard-Knapp G, Piasecki BP, Swoboda P. An Expanded Role for the RFX Transcription Factor DAF-19, with Dual Functions in Ciliated and Nonciliated Neurons. Genetics 2018; 208:1083-1097. [PMID: 29301909 PMCID: PMC5844324 DOI: 10.1534/genetics.117.300571] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 01/02/2017] [Indexed: 02/06/2023] Open
Abstract
Regulatory Factor X (RFX) transcription factors (TFs) are best known for activating genes required for ciliogenesis in both vertebrates and invertebrates. In humans, eight RFX TFs have a variety of tissue-specific functions, while in the worm Caenorhabditis elegans, the sole RFX gene, daf-19, encodes a set of nested isoforms. Null alleles of daf-19 confer pleiotropic effects including altered development with a dauer constitutive phenotype, complete absence of cilia and ciliary proteins, and defects in synaptic protein maintenance. We sought to identify RFX/daf-19 target genes associated with neuronal functions other than ciliogenesis using comparative transcriptome analyses at different life stages of the worm. Subsequent characterization of gene expression patterns revealed one set of genes activated in the presence of DAF-19 in ciliated sensory neurons, whose activation requires the daf-19c isoform, also required for ciliogenesis. A second set of genes is downregulated in the presence of DAF-19, primarily in nonsensory neurons. The human orthologs of some of these neuronal genes are associated with human diseases. We report the novel finding that daf-19a is directly or indirectly responsible for downregulation of these neuronal genes in C. elegans by characterizing a new mutation affecting the daf-19a isoform (tm5562) and not associated with ciliogenesis, but which confers synaptic and behavioral defects. Thus, we have identified a new regulatory role for RFX TFs in the nervous system. The new daf-19 candidate target genes we have identified by transcriptomics will serve to uncover the molecular underpinnings of the pleiotropic effects that daf-19 exerts on nervous system function.
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Affiliation(s)
| | | | - Rosemary J Bauer
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | | | - Sophie A Bice
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Sophie L Scholtz
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Prasad Phirke
- Department of Biosciences and Nutrition, Karolinska Institute, 141 83 Huddinge, Sweden
| | | | - Loraina A Stinson
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Haili B Olson
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Savannah L Vogel
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | | | - Yagmur Esemen
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Jessica Korzynski
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Kelsey Wolfe
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Bonnie N Arbuckle
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - He Zhang
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | | | - Brian P Piasecki
- Department of Biology, Lawrence University, Appleton, Wisconsin 54911
| | - Peter Swoboda
- Department of Biosciences and Nutrition, Karolinska Institute, 141 83 Huddinge, Sweden
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