ABC-Immunitat: guia didàctica

ABC-Immunitat és una guia didàctica de repàs preparada específicament per a la introducció a la immunologia que s'imparteix dintre de l'assignatura Ampliació de biologia cel·lular a la Universitat de Girona. Aquesta guia no pretén de cap manera substituir els llibres d'immunologia. Actualment hi ha al mercat excel·lents textos generals i específics escrits molt acuradament i amb detall. El nostre objectiu és proporcionar un text de lectura ràpida i de fàcil comprensió que reflecteixi una visió general i evolutiva dels sistemes de defensa dels animals. Ens considerarem satisfets si serveix per estimular l'aprenentatge i proporcionar la informació bàsica als nostres alumnes. Necessàriament aquesta guia és incompleta perquè la ciència en què és basa és una de les àrees en progressió més ràpida de la biologia. Molts aspectes estan oberts a important controvèrsia i encara n'hi ha molts que són desconegut

The potato suberin feruloyl transferase FHT which accumulates in the phellogen is induced by wounding and regulated by abscisic and salicylic acids

The present study provides new insights on the role of the potato (Solanum tuberosum) suberin feruloyl transferase FHT in native and wound tissues, leading to conclusions about hitherto unknown properties of the phellogen. In agreement with the enzymatic role of FHT, it is shown that its transcriptional activation and protein accumulation are specific to tissues that undergo suberization such as the root boundary layers of the exodermis and the endodermis, along with the tuber periderm. Remarkably, FHT expression and protein accumulation within the periderm is restricted to the phellogen derivative cells with phellem identity. FHT levels in the periderm are at their peak near harvest during periderm maturation, with the phellogen becoming meristematically inactive and declining thereafter. However, periderm FHT levels remain high for several months after harvest, suggesting that the inactive phellogen retains the capacity to synthesize ferulate esters. Tissue wounding induces FHT expression and the protein accumulates from the first stages of the healing process onwards. FHT is up-regulated by abscisic acid and down-regulated by salicylic acid, emphasizing the complex regulation of suberin synthesis and wound healing. These findings open up new prospects important for the clarification of the suberization process and yield important information with regard to the skin quality of potatoesThe authors thank Professor S. Prat (Centro Nacional de Biotecnologia, Madrid) and Dr E. Dominguez (Centre de Recerca en Agrigenomica CRAG, Barcelona) for providing potato ssp. andigena, for support, and for helpful experimental advice; Dr P. Suarez (CRAG) for kindly lending us the ultracentrifuge; Professor D. Ludevid, Dr S. Irar, and Dr M. P. Gonzalez (CRAG), and Dr T. Roscoe (Institut de Recherche pour le Development, Montpellier) for fruitful suggestions regarding protein and antibody production, immunolocalization, and GUS staining; and Dr J. Castro (Biology Department, University of Girona, UdG) for helpful advice on setting up the western blot conditions. We also thank Mr J. Blavia and D. Reyes (Serveis Tecnics de Recerca, UdG) and S. Gomez (Departament de Biologia, UdG) for their valuable assistance in carrying out the laboratory work. This work was supported by the Ministerio de Innovacion y Ciencia [AGL2009-13745], the Ministerio de Educacion y Ciencia [FPI grant to PB], and the Ministerio de Economia y Competitividad [AGL2012-36725