@article{blackburn_cheng_williamson_goshe_2010, title={Data-independent liquid chromatography/mass spectrometry (LC/MSE) detection and quantification of the secreted Apium graveolens pathogen defense protein mannitol dehydrogenase}, volume={24}, DOI={10.1002/rcm.4476}, abstractNote={Abstract}, number={7}, journal={Rapid Communications in Mass Spectrometry}, author={Blackburn, K. and Cheng, F. Y. and Williamson, J. D. and Goshe, M. B.}, year={2010}, pages={1009–1016} }
 @article{cheng_blackburn_lin_goshe_williamson_2009, title={Absolute Protein Quantification by LC/MSE for Global Analysis of Salicylic Acid-induced Plant Protein Secretion Responses}, volume={8}, ISSN={["1535-3907"]}, DOI={10.1021/pr800649s}, abstractNote={The plant cell wall is a dynamic cellular compartment consisting of a complex matrix of components that can change dramatically in response to environmental stresses. During pathogen attack, for instance, a wide spectrum of proteins that participate in various sequential processes involved in plant defense is secreted into the cell wall. In this study, a mass spectrometry, data-independent acquisition approach known as LC/MS (E) was used to assess temporal changes in the cell wall proteome in response to different levels of an endogenous inducer of plant disease defense responses, salicylic acid (SA). LC/MS (E) was used as a label-free method that enabled simultaneous protein identification and absolute femtomole quantification of each protein secreted into the extracellular matrix. A total of 74 secreted proteins were identified, 63 of which showed increased specific secretion in response to SA. A majority of this induced secretion occurred within 2 h of treatment, indicating that many proteins are involved in the early stages of plant defenses. We also identified a number of apparently nonclassically secreted proteins, suggesting that, as in many nonplant systems, Golgi/ER-independent mechanisms exist for plant protein secretion. These results provide new insight into plant apoplastic defense mechanisms and demonstrate that LC/MS (E) is a powerful tool for obtaining both relative and absolute proteome-scale quantification that can be applied to complex, time- and dose-dependent experimental designs.}, number={1}, journal={JOURNAL OF PROTEOME RESEARCH}, author={Cheng, Fang-yi and Blackburn, Kevin and Lin, Yu-min and Goshe, Michael B. and Williamson, John D.}, year={2009}, month={Jan}, pages={82–93} }
 @article{cheng_zamski_guo_pharr_williamson_2009, title={Salicylic acid stimulates secretion of the normally symplastic enzyme mannitol dehydrogenase: a possible defense against mannitol-secreting fungal pathogens}, volume={230}, ISSN={["1432-2048"]}, DOI={10.1007/s00425-009-1006-3}, abstractNote={The sugar alcohol mannitol is an important carbohydrate with well-documented roles in both metabolism and osmoprotection in many plants and fungi. In addition to these traditionally recognized roles, mannitol is reported to be an antioxidant and as such may play a role in host-pathogen interactions. Current research suggests that pathogenic fungi can secrete mannitol into the apoplast to suppress reactive oxygen-mediated host defenses. Immunoelectron microscopy, immunoblot, and biochemical data reported here show that the normally symplastic plant enzyme, mannitol dehydrogenase (MTD), is secreted into the apoplast after treatment with the endogenous inducer of plant defense responses salicylic acid (SA). In contrast, a cytoplasmic marker protein, hexokinase, remained cytoplasmic after SA-treatment. Secreted MTD retained activity after export to the apoplast. Given that MTD converts mannitol to the sugar mannose, MTD secretion may be an important component of plant defense against mannitol-secreting fungal pathogens such as Alternaria. After SA treatment, MTD was not detected in the Golgi apparatus, and its SA-induced secretion was resistant to brefeldin A, an inhibitor of Golgi-mediated protein transport. Together with the absence of a known extracellular targeting sequence on the MTD protein, these data suggest that a plant's response to pathogen challenge may include secretion of selected defensive proteins by as yet uncharacterized, non-Golgi mechanisms.}, number={6}, journal={PLANTA}, author={Cheng, Fang-yi and Zamski, Eli and Guo, Wei-wen and Pharr, D. Mason and Williamson, John D.}, year={2009}, month={Nov}, pages={1093–1103} }
 @article{cheng_locke_williamson_2008, title={Polyols in plants and pathogens: An integration of transport and function}, volume={9}, journal={Current Topics in Plant Biology}, author={Cheng, F.-Y and Locke, E. and Williamson, J. D.}, year={2008}, pages={101–114} }
 @article{cheng_burkey_robinson_booker_2007, title={Leaf extracellular ascorbate in relation to O(3) tolerance of two soybean cultivars}, volume={150}, ISSN={["0269-7491"]}, DOI={10.1016/j.envpol.2007.01.022}, abstractNote={Soybean [Glycine max (L.) Merr.] cultivars Essex and Forrest that exhibit differences in ozone (O3) sensitivity were used in greenhouse experiments to investigate the role of leaf extracellular antioxidants in O3 injury responses. Charcoal-filtered air and elevated O3 conditions were used to assess genetic, leaf age, and O3 effects. In both cultivars, the extracellular ascorbate pool consisted of 80–98% dehydroascorbic acid, the oxidized form of ascorbic acid (AA) that is not an antioxidant. For all combinations of genotype and O3 treatments, extracellular AA levels were low (1–30 nmol g−1 FW) and represented 3–30% of the total antioxidant capacity. Total extracellular antioxidant capacity was twofold greater in Essex compared with Forrest, consistent with greater O3 tolerance of Essex. The results suggest that extracellular antioxidant metabolites in addition to ascorbate contribute to detoxification of O3 in soybean leaves and possibly affect plant sensitivity to O3 injury.}, number={3}, journal={ENVIRONMENTAL POLLUTION}, author={Cheng, Fang-Yi and Burkey, Kent O. and Robinson, J. Michael and Booker, Fitzgerald L.}, year={2007}, month={Dec}, pages={355–362} }