Dr. Yang Xu

Assistant Professor
Department of Molecular and Cellular Biology
Email: 
yang.xu@uoguelph.ca
Phone number: 
54788
Office: 
SSC 4453
Lab: 
SSC 4401

I received my master’s degree in Food Science from South China University of Technology, where I worked on oil chemistry and bio-catalysis for preparing functional food, specifically functional oils. After that, I moved to Alberta to pursue my PhD in Plant Science with Dr. Randall Weselake at the University of Alberta, where I expanded my research horizons and developed research interests in plant oil synthetic biology and biotechnology. My PhD research focused on engineering enhanced performance in plant lipid biosynthetic enzymes to improve oil accumulation. After completing my doctoral studies, I joined Dr. Guanqun Chen’s laboratory at the University of Alberta as a postdoctoral fellow, where I focused on oil metabolism in microalgae and plant unusual fatty acid biosynthesis. I later moved across the border and joined the laboratory of Dr. Christoph Benning at Michigan State University as a postdoctoral research associate. There, I extended my research focus to chloroplast membrane lipid assembly in photosynthetic organisms. I won the 2021 Carl Douglas Prize from the Canadian Society of Plant Biologists (CSPB/SCBV) in recognition of the contributions to plant biology by a postdoctoral fellow. My interdisciplinary training has shaped my research interest in both fundamental and applied research in the field of plant lipids. My new research group at the University of Guelph will focus on studying lipid metabolism in plants and microalgae, and developing synthetic biology and biotechnology strategies to produce designer oils that meet our growing demand in food, fuel and renewable materials.

Postdoctoral Research Associate – Michigan State University

Postdoctoral Fellow – University of Alberta

PhD – University of Alberta

MSc – South China University of Technology

BSc – Northwest A&F University

The research in the Xu laboratory focuses on plant and microalgal lipid metabolism. By applying state-of-the-art approaches in genetics, biochemistry, cellular biology, synthetic biology and biotechnology, we aim to address both fundamental and applied questions in the field. The major research objectives in our research group are to improve our understanding of the mechanisms underlying acyl lipid assembly (e.g. triacylglycerols/oils, galactolipids/photosynthetic membrane lipids, phospholipids/membrane lipids) in photosynthetic organisms and to design lipid biosynthetic pathways to improve agriculture production and produce value-added oils for food, feed, fuel, and materials applications.

Acyl lipid assembly: Acyl lipids (i.e. lipids derived from fatty acids) are the most abundant lipids in photosynthetic organisms and have essential roles in cells, which include forming membranes, storing energy, and signaling. Photosynthetic organisms are exposed to environmental challenges, and acyl lipid remodeling plays an important role in plant adaption to adverse conditions (e.g. abiotic and biotic stresses). We are interested in identifying and characterizing players and regulators in acyl lipid assembly using an array of approaches ranging from genetics, omics, biochemistry, and cell biology to modeling in order to better understand this process.

Lipid trafficking and channeling: Plant lipid biosynthesis is highly compartmented and involves close coordination of multiple pathways in the ER and chloroplasts and an intense trafficking of lipids between them. Moreover, lipid players may form local interactomes to facilitate substrate channeling. We are exploring the mechanisms by which lipids move across the chloroplast envelope membranes and by which they are transported within the local interactomes.

Lipid synthetic biology and biotechnology: Lipids are important agricultural commodities with broad applications in food, feed, fuel and oleochemical industries. We are interested in designing plants, microalgae, and microorganisms for the production of value-added lipids. Using synthetic biology approaches, we are engineering lipid biosynthetic enzymes and pathways for the synthesis of high-value products.

(*corresponding author)  

  1. Clews A, Ulch B, Jesionowska M, Hong J, Mullen R, Xu Y*. Variety of Plant Oils: Species-Specific Lipid Biosynthesis. Plant Cell and Physiology. 2023, in press. DOI: 10.1093/pcp/pcad147 
  2. Xu Y, Kambhampatib S, Morley S, Cook R, Froehlich J, Allen D, Benning C. Arabidopsis acyl carrier protein 4 and rhomboid like 10 act independently in chloroplast phosphatidic acid assembly. Plant Physiology. 2023, in press. DOI: 10.1093/plphys/kiad483 
  3. Xu Y*, Singer SD, Chen G*. Protein interactomes for plant lipid biosynthesis and their biotechnological applications. Plant Biotechnology Journal. 2023, in press. DOI: 10.1111/pbi.14027  
  4. Jesionowska M, Ovadia J, Hockemeyer K, Clews A, Xu Y*. Recent metabolic engineering advances of EPA and DHA synthesis in microalgae. Journal of the American Oil Chemists' Society. 2023, in press. DOI: 10.1002/aocs.12718 
  5. Xu Q, Tang Q, Xu Y, Wu J, Mao X, Li F, Wang S, Wang Y. Biotechnology in Future Food Lipids: Opportunities and challenges. Annual Review of Food Science and Technology. 2023, 14:225-246. DOI: 10.1146/annurev-food-060721-024353  
  6. Hong J, Rosental L, Xu Y (Co-1st author), … Chen G, Brotman Y, Zhang D, Shi J. Genetic architecture of seed glycerolipids in Asian cultivated rice. Plant, Cell & Environment. 2023, 46: 1278-1294. DOI: 10.1111/pce.14378  
  7. Xiao Q, Pan X, Xu Y, Singer S, Chen G. Genome-wide characterization of plant CTP:phosphocholine cytidylyltransferases through evolutionary, biochemical and structural analyses. The Plant Journal. 2023, in press. DOI: 10.1111/tpj.16264 
  8. McDonald K, Xu Y, Chen G. A simple and cost-effective direct transmethylation procedure for plant lipid analysis. Journal of the American Oil Chemists' Society. 2023, in press. DOI: 10.1002/aocs.12709 
  9. Xu Y*. Biochemistry and biotechnology of lipid accumulation in the microalga Nannochloropsis oceanica. Journal of Agricultural and Food Chemistry. 2022, 70: 11500-11509. DOI: 10.1021/acs.jafc.2c05309  
  10. Lavell A, Smith M, Xu Y, Froehlich JE, De La Mora C, Benning C. Proteins associated with the Arabidopsis thaliana plastid rhomboid‐like protein RBL10. The Plant Journal. 2021, 108: 1332-1345. DOI: 10.1111/tpj.15514  
  11. Xu Y, Pan X, Lu J, Wang J, Shan Q, Stout J, Chen G. Evolutionary and biochemical characterization of a Chromochloris zofingiensis MBOAT with wax synthase and DGAT activity. Journal of Experimental Botany. 2021, 72: 5584–5598. DOI: 10.1093/jxb/erab236  
  12. Xu Y, Caldo KMP, Singer S, Greer M, Mietkiewska E, Tian B, Dyer J, Stymne S, Smith M, Zhou XR, Qiu X, McKeon T, Weselake R, Chen G. Physaria fendleri and Ricinus communis LCAT-like phospholipases selectively cleave hydroxy acyl chains from phosphatidylcholine. The Plant Journal. 2021, 105: 182–196. DOI: 10.1111/tpj.15050  
  13. Wang J, Xu Y, Holic R, Yu X, Singer SD, Chen G. Improving the production of punicic acid in baker’s yeast by engineering genes in acyl channeling processes and adjusting precursor supply. Journal of Agricultural and Food Chemistry. 2021: 69: 9616-9624. DOI: 10.1021/acs.jafc.1c03256  
  14. Cui Y, Zeng X, Xiong Q, Wei D, Liao J, Xu Y, Chen, G, Zhou Y, Dong H, Wang H, Liu Z, LI J, Guo L, Jung C, He Y, Qian W. Combining QTL and co-expression analysis allowed identification of new candidates for oil accumulation in rapeseed. Journal of Experimental Botany. 2021, 72: 1649-1660. DOI: 10.1093/jxb/eraa563  
  15. Xin H, Ma T, Xu Y, Chen G, Chen Y, Villot C, Steele MA, Guan LL. Characterization of fecal branched-chain fatty acids profiles and their associations with fecal microbiota in diarrheic and healthy dairy calves. Journal of Dairy Science. 2021, 104: 2290-2301. DOI: 10.3168/jds.2020-18825  
  16. Xu Y, Mietkiewska E, Shah S, Weselake RJ, Chen G. Punicic acid production in Brassica napus. Metabolic Engineering. 2020, 62: 20–29. DOI: 10.1016/j.ymben.2020.08.011  
  17. Xu Y, Caldo KMP, Farlaz L, Jayawardhane K, Chen G. Kinetic improvement of an algal diacylglycerol acyltransferase 1 via fusion with an acyl-CoA binding protein. The Plant Journal. 2020, 102: 856–871. # Cover of the issue. DOI: 10.1111/tpj.14708  
  18. Xu Y, Singer SD, Chen G. Improving oil production in plants and microalgae by engineering performance-enhanced diacylglycerol acyltransferase 1. Inform. 2020, 31, 20–23. DOI: 10.21748/inform.06.2020.20  
  19. Falarz L, Xu Y, Caldo KMP, Garroway CJ, Singer SD, Chen G. Characterization of the diversification of phospholipid:diacylglycerol acyltransferases in the green lineage. The Plant Journal. 2020, 103: 2025-2038. DOI: 10.1111/tpj.14880  
  20. Nguyen T, Xu Y, Abdel-Hameed M, Sorensen JL, Singer SD, Chen G. Characterization of a type-2 diacylglycerol acyltransferase from Haematococcus pluvialis reveals possible allostery of the recombinant enzyme. Lipids. 2020, 55: 425-433. DOI: 10.1002/lipd.12210  
  21. Lu J, Xu Y, Wang J, Singer SD, Chen G. The role of triacylglycerol in plant stress response. Plants. 2020, 9: 472. DOI: 10.3390/plants9040472  
  22. Xin H, Xu Y, Chen Y, Chen G, Steele MA, Guan LL. Odd-chain and branched-chain fatty acids concentrations in bovine colostrum and transition milk and their stability under heating and freezing treatments. Journal of Dairy Science. 2020, 103(12): 11483-11489. DOI: 10.3168/jds.2020-18994  
  23. Xu Y, Caldo KMP, Jayawardhane K, Ozga J, Weselake R, Chen G. A transferase interactome may facilitate channeling of polyunsaturated fatty acid moieties from phosphatidylcholine into triacylglycerol. Journal of Biological Chemistry. 2019, 294:14838–14844. # Cover of the issue. DOI: 10.1074/jbc.AC119.010601  
  24. Caldo KMP, Xu Y (Co-1st author), Farlaz L, Jayawardhane K, Chen G. Arabidopsis CTP:phosphocholine cytidylyltransferase 1 is phosphorylated and inhibited by sucrose nonfermenting 1–related protein kinase 1 (SnRK1). Journal of Biological Chemistry. 2019, 294: 15862–15874. # Recommended in F1000Prime. DOI: 10.1074/jbc.RA119.008047  
  25. Xu Y, Caldo KMP, Mietkiewska E, Holic R, Ozga J, Chen G, Weselake RJ. Engineering Arabidopsis long-chain acyl-CoA synthetase 9 variants with enhanced enzyme activity. Biochemical Journal. 2019, 476 (1): 151–164. DOI: 10.1042/BCJ20180787  
  26. Xu Y, Falarz L, Chen G. Characterization of type-2 diacylglycerol acyltransferases in the green microalga Chromochloris zofingiensis. Journal of Agricultural and Food Chemistry. 2019, 67(1): 291–298. DOI: 10.1021/acs.jafc.8b05755  
  27. Tian B, Lu T, Xu Y, Wang R, Chen G. Identification of genes associated with ricinoleic acid accumulation in Hiptage benghalensis via transcriptome analysis. Biotechnology for Biofuels. 2019, 12:16. DOI: 10.1186/s13068-019-1358-2  
  28. Falarz L, Xu Y, Singer SD, Chen G. A fluorescence-based assay for quantitative analysis of phospholipid:diacylglycerol acyltransferase activity. Lipids. 2019, 54(9): 571-579. DOI: 10.1002/lipd.12190  
  29. Xu Y, Caldo KMP, Pal-Nath D, Petrie J, Ozga J, Lemieux MJ, Weselake RJ, Chen G. Properties and biotechnological applications of acyl-CoA:diacylglycerol acyltransferase and phospholipid:diacylglycerol acyltransferase from terrestrial plants and microalgae. Lipids. 2018, 53(7): 663–688. DOI: 10.1002/lipd.12081  
  30. Xu Y, Holic R, Li D, Pan X, Mietkiewska E, Chen G, Ozga J, Weselake RJ. Substrate preferences of long-chain acyl-CoA synthetase and diacylglycerol acyltransferase contribute to enrichment of flax seed oil with α-linolenic acid. Biochemical Journal. 2018, 475(8):1473–1489. DOI: 10.1042/BCJ20170910  
  31. Caldo K, Shen W, Xu Y, Hanley-Bowdoin L, Chen G, Weselake R, Lemieux MJ. Diacylglycerol acyltransferase 1 is activated by phosphatidate and inhibited by SnRK 1‐catalyzed phosphorylation. The Plant Journal. 2018, 96: 287-299. DOI: 10.1111/tpj.14029  
  32. Holic R, Xu Y, Caldo K, Singer SD, Field CJ, Weselake RJ, Chen G. Bioactivity and biotechnological production of punicic acid. Applied Microbiology and Biotechnology. 2018, 102: 3537-3549. DOI: 10.1007/s00253-018-8883-y  
  33. Xu Y, Chen G, Greer M, Caldo KMP, Ramakrishnan G, Shah S, Wu L, Lemieux MJ, Ozga J, Weselake RJ. Multiple mechanisms contribute to increased neutral lipid accumulation in yeast producing recombinant variants of plant diacylglycerol acyltransferase 1. Journal of Biological Chemistry. 2017, 292: 17819–17831. DOI: 10.1074/jbc.M117.811489  
  34. Chen G, Xu Y, Rodrigo S, Clado K, Vanhercke T, EI Tahchy A, Niesner N, Chen Y, Mietkiewska E, Weselake RJ. High-performance variants of plant diacylglycerol acyltransferase 1 generated by directed evolution provide insights into structure function. The Plant Journal. 2017, 92: 167-177.  # Featured article of the issue & the subject of a Research Highlight article. DOI: 10.1111/tpj.13707  

 

Graduate Students:  

Alyssa Clews (PhD student, co-supervised with Dr. Mullen)  

Brandon Ulch (MSc student)  

 

Research Technician:   

Monika Jesionowska, MSc    

 

Research Project Students and Undergraduate Students:    

Sean Balogh (4th research project)    

Natalie Bowering (4th research project)    

 

Previous Lab Members  

Justin Ovadia (USRA, 4th research project)    

Kathryn Fletcher (4th research project)    

Hanxiao Wu (Project SOY) 

Adriana Lang (4th research project)    

Samantha Reis (URA)  

Daniel Pulcina (MBIOT student) 

  

Graduate Student Opportunities:  

We are actively recruiting motivated undergraduate and graduate (MSc and PhD) students. Please contact me (yangxu@uoguelph.ca) directly for more information.