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Dr. C.J. Tsai

Winfred N. "Hank" Haynes Professor
Georgia Research Alliance Eminent Scholar

I am a plant biologist with a special passion for large organisms - trees! Trees are ‘large' not merely by their physical or genome size, but primarily by their longevity. Longevity depends on a perennial growth habit, which can mean added functionalities for genes, proteins, and metabolites compared to herbaceous annuals. The quest for 'what makes a tree a tree' has led to various projects ranging from gene family evolution and functional diversification to transgenic manipulation of traits important to growth and development. Needless to say, our research has industrial relevance due to the importance of forest trees as renewable feedstock. Our work is also of ecological relevance because many of the traits we investigate are important in tree interactions with herbivores and pathogens.

We use a variety of experimental approaches in our investigations, ranging from transcriptomics, metabolomics and CRISPR genome editing, to the more traditional tools of genetics, biochemistry and plant physiology. We accept technical challenges and have many times developed or adapted necessary tools to advance our research. For this reason, our lab regularly hosts visiting scholars for technical training, such as in situ hybridization, genome editing, and metabolomic analysis.

Current Graduate Students:
Ing-Gin Chen (Ph.D.), Forest Biology
Yen-Ho Chen (Ph.D.), Plant Biology
Chen Hsieh (Ph.D.), Bioinformatics
Samantha Surber (Ph.D.), Plant Biology
Trevor Tuma (Ph.D.), Forest Biology
Audrey Widmier (Ph.D.), Plant Biology

Research Staff:
Michihito Deguchi, Postdoctoral Associate
Margot Chen, Research Professional I
Makenzie Drowns, Research Technician
Brent Lieb, Research Technician
Kimberly McInnes, Research Technician
Khadijeh Mozaffari, Research Professional III, Plant Metabolomics Lab
Batbayar (Baggi) Nyamdari, Research Professional III
Maria Ortega, Senior Research Associate
Saurabh Pandey, Postdoctoral Associate
Alisa Tannirat, Research Professional II
Antt Htet Wai, Postdoctoral Associate
Daniela Weber, Research Professional 
Ran Zhou, Postdoctoral Associate

Selected Publications:

Ortega MA, Zhou R, Chen MSS, Bewg WP, Simon B, Tsai C-J (2023) In vitro floral development in poplar: insights into seed trichome regulation and trimonoecy. New Phytologist 237: 1078-1081. Reprint  

Harding SA, Tuma TT, Aulakh K, Ortega MA, Ci D, Ou Y, Tsai C-J (2022) Tonoplast sucrose trafficking modulates starch utilization and water deficit behavior in poplar leaves. Plant Cell Physiology 63: 1117–1129. Reprint

Ullah C, Schmidt A, Reichelt M, Tsai C-J, Gershenzon J (2022) Lack of antagonism between salicylic acid and jasmonate signaling pathways in poplar. New Phytologist 235: 701-717. Reprint

Bewg WP, Harding SA, Engle N, Vaidya BN, Zhou R, Reeves J, Horn TW, Joshee N, Jenkins J, Shu S, Barry KW, Yoshinaga Y, Grimwood J, Schmitz RJ, Schmutz J, Tschaplinski TJ, Tsai C-J (2022) Multiplex knockout of trichome-regulating MYB duplicates in hybrid poplar using a single gRNA. Plant Physiology 189: 516–526. Reprint

Gu X, Chen I-G, Tsai C-J (2021) How do holoparasitic plants exploit vitamin K1? Plant Signaling & Behavior 16: 11. Reprint

Gu X, Chen I-G, Harding SA, Nyamdari B, Ortega MA, Clermont K, Westwood JH, Tsai C-J (2021) Plasma membrane phylloquinone biosynthesis in nonphotosynthetic parasitic plants. Plant Physiology (2021 Focus Issue on Parasitic Plants). Full text.

Tsai C-J (2021) genome editing of woody perennial trees. In: M. Willmann (ed), Genome Editing for Precision Crop breeding. Burleigh Dodds Science Publishing, Cambridge, UK. 

Harding SA, Frost CJ, Tsai CJ (2020) Defoliation‐induced compensatory transpiration is compromised in SUT4‐RNAi Populus. Plant Direct 4: 1-13. Full text

Tsai C-J, Xu P, Xue L-J, Hu H, Nyamdari B, Naran R, Zhou X, Goeminne G, Gao R, Gjersing E, Dahlen J, Pattathil S, Hahn MG, Davis MF, Ralph J, Boerjan W, Harding SA (2020) Compensatory guaiacyl lignin biosynthesis at the expense of syringyl lignin in 4CL1-knockout poplar. Plant Physiology 183: 123-136. Full text

Ullah C, Tsai C-J, Unsicker S, Xue L-J, Reichelt M, Gershenzon J, Hammerbacher A (2019) Salicylic acid activates poplar defense against the biotrophic rust fungus Melampsora larici-populina via increased accumulation of catechin and proanthocyanidins. New Phytologist. 221: 960-975. Full text 

Harding SA, Tsai CJ (2019) Cell wall pectins in tree growth and woody biomass utilization. In: Canovas FM (ed.), Advances in Botanical Research Vol 89: Molecular Physiology and Biotechnology of Trees. Academic Press, pp. 235-256. 

Bewg WP, Ci D, Tsai C-J (2018) Genome editing in trees: From multiple repair pathways to long-term stability. Frontiers in Plant Science 9:1732.  Full text

Harding SA, Hu H, Nyamdari B, Xue L-J, Naran R, Tsai C-J (2018) Tubulins, rhythms and cell walls in poplar leaves: it’s all in the timing. Tree Physiology 38: 397-408.  Full text

Hu H, Gu X, Xue L-J, Swamy PS, Harding SA, Tsai C-J (2016) Tubulin C-terminal post-translational modifications do not occur in wood forming tissue of Populus. Frontiers in Plant Science 7, 1493. Full text
Xue L-J, Frost CJ, Tsai C-J, Harding SA (2016) Drought response transcriptomes are altered in poplar with reduced tonoplast sucrose transporter expression. Scientific Reports 6, 33655. Full text

Tsai C-J, Xue L-J (2015) CRISPRing into the woods. GM Crops & Food 6: 206-215. Full text

Swamy PS, Hu H, Pattathil S, Maloney VJ, Xiao H, Xue L-J, Chung J-D, Johnson VE, Zhu Y, Peter GF, Hahn MG,  Mansfield SD, Harding SA, Tsai C-J (2015) Tubulin perturbation leads to unexpected cell wall modifications and affects stomatal behavior in Populus. Journal of Experimental Botany 66: 6507-6518.  Full text

Xue L-J, Alabady MS, Mohebbi M, Tsai C-J (2015) Exploiting genome variation to improve next-generation sequencing data analysis and genome editing efficiency inPopulus tremula x alba 717-1B4.  ree Genetics & Genomes 11: 82. Full text

Xue L-J, Tsai C-J (2015) AGEseq: Analysis of genome editing by sequencing. Molecular Plant 8: 1428-1430. Full text

Zhou X, Jacobs TB, Xue L-J, Harding S, Tsai C-J (2015) Exploiting SNPs for biallelic CRISPR mutations in the outcrossing woody perennial Populus reveals 4-coumrate:CoA ligase specificity and redundancy. New Phytologist 208: 298-301. Full text

Harding SA, Xue L-J, Du L, Nyamdari B, Lindroth RL, Sykes R, Davis MF, Tsai C-J (2014) Condensed tannin biosynthesis and polymerization synergistically condition carbon use, defense, sink strength and growth in PopulusTree Physiology 34: 1240-1251Full text

Peng D, Gu X, Xue L-J, Leebens-Mack JH, Tsai C-J (2014) Bayesian phylogeny of sucrose transporters: Ancient origins, differential expansion and convergent evolution in monocots and dicots.  Frontiers in Plant Science 5: 615.  Full text

Chen H-Y, Babst BA, Nyamdari B, Sykes R, Davis MF, Harding SA, Tsai C-J (2014) Loblolly pine contains phylogenetically divergent 4-coumarate:CoA ligases that confer distinct metabolic phenotypes when over-expressed in PopulusPlant Cell Physiology 55: 1669-1678Full text

Babst BA, Chen H-Y, Wang H-Q, Payyavula RS, Thomas TP, Harding SA, Tsai C-J (2014) Stress responsive Populus hydroxycinnamate glycosyltransferase modulates phenylpropanoid homeostasis.  Journal of Experimental Botany 65: 4191-4200. Full text

Xue L-J, Guo W, Yuan Y, Anino EO, Nyamdari B, Wilson MC, Frost CJ, Chen H-Y, Babst BA, Harding SA, Tsai CJ (2013) Constitutively elevated salicylic acid levels alter photosynthesis and oxidative state but not growth in transgenic PopulusPlant Cell 25: 2714-2730.  Full text Image removed.

Current grants:

Tsai C-J, Muchero W, Ranjan P, WINTR: Winter transcriptome regulation in poplar. DOE

Buell CR, Dardick C, Parrott W, Schmitz R, Shih P, Tsai C-J, Urbanowicz B, BioPoplar: a tunable chassis for diversified bioproduct production. DOE

Tuskan GA et al., The Center for Bioenergy Innovation II. DOE Bioenergy Research Center

Yang L, Tsai C-J, Investigate the roles of endogenous salicylic acid in de novo organogenesis. NSF

Tsai C-J, Brewer MT, McGregor CE, Smith SM, van der Knaap E, Crop Genetics and Genomics II: Promoting diversity in agriscience through undergraduate mentoring in research and extension. USDA-AFRI

Tsai C-J, Donovan LA, Harding SA, Li Z, Mitchum MG, Villari C, Yang L, ultrahigh performance liquid chromatography-tandem mass spectrometry for metabolite profiling in crop and forestry research. USDA-AFRI

Research Areas:

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