Kurdyukov, Sergey Faust, Andrea Nawrath, Christiane Bär, Sascha Voisin, Derry Efremova, Nadia Franke, Rochus Schreiber, Lukas Saedler, Heinz Métraux, Jean-Pierre Yephremov, Alexander 2006-01-13 The outermost epidermal cell wall is specialized to withstand pathogens and natural stresses, and lipid-based cuticular polymers are the major barrier against incursions. The <i>Arabidopsis thaliana</i> mutant <i>bodyguard</i> (<i>bdg</i>), which exhibits defects characteristic of the loss of cuticle structure not attributable to a lack of typical cutin monomers, unexpectedly accumulates significantly more cell wall–bound lipids and epicuticular waxes than wild-type plants. Pleiotropic effects of the <i>bdg</i> mutation on growth, viability, and cell differentiation are also observed. <i>BDG</i> encodes a member of the α/ß-hydrolase fold protein superfamily and is expressed exclusively in epidermal cells. Using Strep-tag epitope-tagged BDG for mutant complementation and immunolocalization, we show that BDG is a polarly localized protein that accumulates in the outermost cell wall in the epidermis. With regard to the appearance and structure of the cuticle, the phenotype conferred by <i>bdg</i> is reminiscent of that of transgenic <i>Arabidopsis</i> plants that express an extracellular fungal cutinase, suggesting that <i>bdg</i> may be incapable of completing the polymerization of carboxylic esters in the cuticular layer of the cell wall or the cuticle proper. We propose that <i>BDG</i> codes for an extracellular synthase responsible for the formation of cuticle. The alternative hypothesis proposes that BDG controls the proliferation/differentiation status of the epidermis via an unknown mechanism. application/pdf https://folia.unifr.ch/global/documents/300091 https://folia.unifr.ch/documents/300091/files/1_metraux_ese.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1105/tpc.105.036079 info:eu-repo/semantics/openAccess License undefined The Plant Cell. - 2006, vol. 18, no. 2, p. 321-339 info:eu-repo/classification/udc/57 The epidermis-specific extracellular BODYGUARD controls cuticle development and morphogenesis in Arabidopsis http://purl.org/coar/resource_type/c_6501