Modification of cell wall properties in lettuce improves shelf life
Wagstaff, C., Clarkson, G. J. J., Zhang, F., Rothwell, S. D., Fry, S. C., Taylor, G. and Dixon, M. S. (2010) Modification of cell wall properties in lettuce improves shelf life. Journal of Experimental Botany, 61 (4). pp. 1239-1248. ISSN 0022-0957
To link to this article DOI: 10.1093/jxb/erq038
It is proposed that post-harvest longevity and appearance of salad crops is closely linked to pre-harvest leaf morphology (cell and leaf size) and biophysical structure (leaf strength). Transgenic lettuce plants (Lactuca sativa cv. Valeria) were produced in which the production of the cell wall-modifying enzyme xyloglucan endotransglucosylase/hydrolase (XTH) was down-regulated by antisense inhibition. Independently transformed lines were shown to have multiple members of the LsXTH gene family down-regulated in mature leaves of 6-week-old plants and during the course of shelf life. Consequently, xyloglucan endotransglucosylase (XET) enzyme activity and action were down-regulated in the cell walls of these leaves and it was established that leaf area and fresh weight were decreased while leaf strength was increased in the transgenic lines. Membrane permeability was reduced towards the end of shelf life in the transgenic lines relative to the controls and bacteria were evident inside the leaves of control plants only. Most importantly, an extended shelf-life of transgenic lines was observed relative to the non-transgenic control plants. These data illustrate the potential for engineering cell wall traits for improving quality and longevity of salad crops using either genetic modification directly, or by using markers associated with XTH genes to inform a commercial breeding programme.
Baluska F, Samaj J, Wojtaszek P, Volkmann D, Menzel D. 2003. Cytoskeleton-plasma membrane-cell wall continuum in plants. Emerging links revisited. Plant Physiology 133, 482-491. Brummell DA, Harpster MH, Civello PM, Palys JM, Bennett AB, Dunsmuir P. 1999. Modification of expansin protein abundance in tomato fruit alters softening and cell wall polymer metabolism during ripening. Plant Cell 11, 2203-2216. Clarkson GJJ. 2004. The diagnosis and manipulation of baby salad leaf processability. PhD thesis. University of Southampton, Southampton Clarkson GJJ, O’ Byrne EE, Rothwell SD, Taylor G. 2003. Identifying traits to improve postharvest processability in baby leaf salad. Postharvest Biology and Technology 30, 287-298. Clarkson GJJ, Rothwell SD, Taylor G. 2005. End of day harvest extends shelf life. Hortscience 40, 1431-1435. Curtis IS, Power JB, Blackhall NW, de Laat AMM, Davey MR. 1994. Genotype-independent transformations of lettuce using Agrobacterium tumefaciens. Journal of Experimantal Botany 45, 1441-1449. Dimmer E, Roden L, Cai D, Kingsnorth C, Mutasa-Göttgens E. 2004. Transgenic analysis of sugar beet xyloglucan endotransglucosylase/hydrolase Bv-XTH1 and BvXTH2 promoters reveals overlapping tissue-specific and wound inducible expression profiles. Plant Biotechnology Journal 2, 127-139. Fry SC, Smith RC, Renwick KF, Martin DJ, Hodge SK, Matthews KJ. 1992. Xyloglucan endotransglycosylase, a new wall-loosening enzyme activity from plants. Biochemical Journal 282, 821-828. Fry SC. 1989. Cellulases, hemicelluloses and auxin-stimulated growth – a possible relationship. Physiologia Planta 75, 532-536. Fry SC. 2004. Primary cell wall metabolism: tracking the careers of wall polymers in living plant cells. New Phytologist 161, 641-675. Henikoff S, Till BJ, Comai L. 2004. TILLING: Traditional mutagenesis meets functional genomics. Plant Physiology 135, 630-636. Humphrey TV, Bonetta DT, Goring DR. 2007. Sentinels at the wall: cell wall receptors and sensors. New Phytologist 176, 7-21. Jones JDG, Shulumukov L, Carland F, Engllish J, Scofield SR, Bishop GJ, Harrison K. 1992. Effective vectors for transformation, expression of heterologous genes, and assaying transposon excision in transgenic plants. Transgenic Research 1, 285-297. Matsui A, Yokoyama R, Seki M, Ito T, Shinozaki K, Takahashi T, Komeda Y, Nishitani K. 2005. AtXTH27 plays an essential role in cell wall modification during the development of tracheary elements. Plant Journal 42, 525-534. McCann MC, Wells B, Roberts K. 1990. Direct visualization of cross-links in the primary plant-cell wall. Journal of Cell Science 96, 323-334. McQueen-Mason SJ, Fry SC, Durachko DM, Cosgrove DJ. 1993. The relationship between xyloglucan endotransglycosylase and in vitro cell wall extension in cucumber hypocotyls. Planta 190, 327-331. Mellersh DG, Heath MC. 2001. Plasma membrane-cell wall adhesion is required for expression of plant defense responses during fungal penetration. Plant Cell 13, 413¬-424. Newman JM, Hilton HW, Clifford SC, Smith AC. 2005. The mechanical properties of lettuce: A comparison of some agronomic and postharvest effects. J Materials Science 40, 1101-1104. Nishitani K, Tominaga T. 1992. Endo-xyloglucan transferase, a novel class of glycosyltransferase that catalyzes transfer of a segment of xyloglucan molecule to another xyloglucan molecule. J Biological Chemistry 267, 21058-21064. Nishitani K. 2005. Division of roles among members of the XTH gene family in plants. Plant Biosystems 139, 98-101. Palmer SJ, Davies WJ. 1996. An analysis of relative elemental growth rate, epidermal cell size and xyloglucan endotransglycosylase activity through the growing zone of ageing maize leaves. Journal of Experimental Botany 47, 339-347. Pilling E, Höfte H. 2003. Feedback from the wall. Current Opinions in Plant Biology 6, 611-616. Pritchard J, Hetherington PR, Fry SC, Tomos AD. 1993. Xyloglucan endotransglycosylase activity, microfibril orientation and the profiles of cell wall properties along growing regions of maize roots. Journal of Experimantal Botany 44, 1281-1289 Ramakers C, Ruijter JM, Lekanne Deprez RH, Moorman AFM. 2003. Assumption-free analysis of quantitative real-time PCR data. Neuroscience Letters 39, 62-66 Rose JKC, Braam J, Fry SC, Nishitani K. 2002. The XTH family of enzymes involved in xyloglucan endotransglucosylation and endohydrolysis: current perspectives and a new unifying nomenclature. Plant and Cell Physiology 43, 1421-1435. Smith DL, Abbott JA, Gross KC. 2002. Down-regulation of tomato beta-galactosidase 4 results in decreased fruit softening. Plant Physiology 129, 1755-1762. Street NR, Skogstrom O, Sjodin A, Tucker J, Rodriguez-Acosta M, Nilsson P, Jansson S, Tayor G. 2006. The genetics and genomics of drought response in Populus. Plant Journal, 48, 321-341. Thompson JE, Fry SC. 2001. Restructuring of wall-bound xyloglucan by transglycosylation in living plant cells. Plant Journal 26, 23-34. Vissenberg K, Fry SC, Pauly M, Höfte H, Verbelen J-P. 2005. XTH acts at the microfibril–matrix interface during cell elongation. Journal of Experimantal Botany 56, 673-683. Vissenberg K, Martinez-Vilchez IM, Verbelen J-P, Miller JG, Fry SC. 2000. In vivo co-localization of xyloglucan endotransglycosylase activity and its donor substrate in the elongation zone of Arabidopsis roots. Plant Cell 12, 1229-1238. Wagstaff C, Clarkson GJJ, Rothwell SD, Page A, Taylor G, Dixon MS. 2007. Characterisation of cell death in bagged baby salad leaves. Postharvest Biology and Technology 46, 150-159. Xu W, Purugganan MM, Polisensky DH, Antosiewicz DM, Fry SC, Braam J. 1995. Arabidopsis TCH4, regulated by hormones and the environment, encodes a xyloglucan endotransglycosylase. Plant Cell 7, 1555-1567. Xu W, Campbell P, Vargheese AK, Braam J. 1996. The Arabidopsis XET-related gene family: environmental and hormonal regulation of expression. Plant Journal 9, 879¬. Yokoyama R, Rose JKC, Nishitani K. 2004. A surprising diversity and abundance of xyloglucan endotransglucosylase/hydrolases in rice. Classification and expression analysis. Plant Physiology 134, 1088-99. Zhang FZ, Wagstaff C, Rae AM, Sihota AK, Keevil CW, Rothwell SD, Clarkson GJJ, Michelmore RW, Truco MJ, Dixon MS, Taylor G. 2007. QTL for shelf life in lettuce co-locate with those for leaf biophysical properties but not for leaf developmental traits. Journal of Experimental Botany 58, 1433-1449. Zhang FZ. 2006. The genetic basis of salad leaf processability. PhD thesis, University of Southampton. Zimmermann P, Hirsch-Hoffmann M, Hennig L, Gruissem W. 2004. GENEVESTIGATOR. Arabidopsis Microarray Database and Analysis Toolbox. Plant Physiology 136, 2621-2632.