2026-04-14T09:12:56Zhttps://recercat.cat/oai/request

oai:recercat.cat:20.500.12327/34002025-10-22T11:16:15Zcom_2072_4428com_2072_4427col_2072_487898

ZmXTH1, a new xyloglucan endotransglucosylase/ hydrolase in maize, affects cell wall structure and composition in Arabidopsis thaliana Genovesi, Valeria Fornalé, Silvia Fry, Stephen C. Ruel, Katia Ferrer, Pau Encina, Antonio Sonbol, Fathi-Mohamed Bosch, Josep Puigdomènech, Pere Rigau, Joan Caparrós-Ruiz, David Producció Vegetal Genòmica i Biotecnologia 633 Xyloglucan endotransglucosylase/hydrolases (XTHs; EC 2.4.1.207 and/or EC 3.2.1.151) are enzymes involved in the modification of cell wall structure by cleaving and, often, also re-joining xyloglucan molecules in primary plant cell walls. Using a pool of antibodies raised against an enriched cell wall protein fraction, a new XTH cDNA in maize, ZmXTH1, has been isolated from a cDNA expression library obtained from the elongation zone of the maize root. The predicted protein has a putative N-terminal signal peptide and possesses the typical domains of this enzyme family, such as a catalytic domain that is homologous to that of Bacillus macerans b-glucanase, a putative Nglycosylation motif, and four cysteine residues in the central and C terminal regions of the ZmXTH1 protein. Phylogenetic analysis of ZmXTH1 reveals that it belongs to subgroup 4, so far only reported from Poaceae monocot species. ZmXTH1 has been expressed in Pichia pastoris (a methylotrophic yeast) and the recombinant enzyme showed xyloglucan endotransglucosylase but not xyloglucan endohydrolase activity, representing the first enzyme belonging to subgroup 4 characterized in maize so far. Expression data indicate that ZmXTH1 is expressed in elongating tissues, modulated by culture conditions, and induced by gibberellins. Transient expression assays in onion cells reveal that ZmXTH1 is directed to the cell wall, although weakly bound. Finally, Arabidopsis thaliana plants expressing ZmXTH1 show slightly increased xyloglucan endohydrolase activity and alterations in the cell wall structure and composition. This work was funded by the Spanish ‘Ministerio de Ciencia y Tecnologı´a’ (BIO2001-1140). VG was financed by a pre-doctoral grant from the ‘Generalitat de Catalunya’ (2003-FI00090). In addition, VG was funded by two grants from the Generalitat de Catalunya (2005-BE00104 and 2006-BE00668) for her work performed at Professor Fry’s and Dr Ruel’s laboratories. SF was financed by a post-doctoral grant from the ‘Generalitat de Catalunya’ (2003PIV-A-00033) and by an I3P contract from the ‘Consejo Superior de Investigaciones Cientı´ficas’. DC-R was financed by the Spanish ‘Ministerio de Educacion y Ciencia’ (‘Ramon y Cajal’ Program). This work was carried out within the framework of the ‘Xarxa de Refere `ncia en Biotecnologia’ from the ‘Generalitat de Catalunya’. SCF was funded by the UK Biotechnology and Biological Sciences Research Council. We are indebted to Dr Castresana (IBMB-CSIC) for his advice on the phylogenetic analyses, Dr Capellades for her technical support and the sequencing, and the greenhouse teams of IBMB-CSIC. info:eu-repo/semantics/publishedVersion 2008-03-02 info:eu-repo/semantics/article Genovesi, Valeria, Silvia Fornalé, Stephen C. Fry, Katia Ruel, Pau Ferrer, Antonio Encina, Fathi-Mohamed Sonbol, et al. 2008. “ZmXTH1, a New Xyloglucan Endotransglucosylase/Hydrolase in Maize, Affects Cell Wall Structure and Composition in Arabidopsis Thaliana.” Journal of Experimental Botany 59 (4): 875–89. doi: 10.1093/jxb/ern013 0022-0957 http://hdl.handle.net/20.500.12327/3400 https://doi.org/10.1093/jxb/ern013 eng Journal of Experimental Botany Attribution-NonCommercial 4.0 International http://creativecommons.org/licenses/by-nc/4.0/ info:eu-repo/semantics/openAccess 15 Oxford University Press