INSTITUTO DE FISIOLOGIA VEGETAL
Unidad Ejecutora - UE
congresos y reuniones científicas
SKIP1 is a novel plant specific protein involved in both endosomal and the autophagy pathways. Evidence for its role in leaf senescence
DANA MARTINEZ ; MARISA OTEGUI
Congreso; Plant Biology & Botany Congress; 2011
American Society of Plant Biology
Endosomal trafficking allows membrane protein internalization and transport through different cellcompartments, from the plasma membrane to endosomes, and from there to the vacuole fordegradation. Proteins targeted for degradation are recognized at the endosome surface by proteincomplexes called ESCRTs ation of membrane proteins into internal vesicles with the criticalinvolvement of the ATPase SKD1. A Yeast Two Hybrid Assays identified a novel SKD1 interactingprotein that we called SKIP1 (SKD1 Interacting Protein 1). SKIP1 is a plant specific protein that isup-regulated during leaf senescence. The analysis of Arabidopsis skip1 knock out plants showeddifferences in the timing of dark induced senescence. The skip1 leaves showed accelerated lossof ns and chlorophyll compared to WT. SKIP1 and the autophagic gene ATG8, which plays afundamental role during macroautophagy show a similar up-regulation during leaf senescence. Inaddition, we have found that SKIP1 and ATG8 interact in in vitro pull down experiments and thatthat interaction is mediated by an AIM (ATG8 Interacting Domain) found in SKIP1 and in manyanimal autophagic receptors. These results suggest a novel crosstalk between the endosomal andautophagy pathways that regulate protein degradation during leaf senescence.