New paper from Isono and Braun lab.

FYVE1 is essential for vacuole biogenesis and intracellular trafficking in Arabidopsis thaliana

Cornelia Kolb, Marie-Kristin Nagel, Kamila Kalinowska, Jörg Hagmann, Mie Ichikawa, Franziska Anzenberger, Angela Alkofer, Masa H. Sato, Pascal Braun and Erika Isono.

Plant Physiol.

The plant vacuole is a central organelle that is involved in various biological processes throughout the plant life cycle. Elucidating the mechanism of vacuole biogenesis and maintenance is thus the basis for our understanding of these processes. Proper formation of the vacuole has been shown to depend on the intracellular membrane trafficking pathway. Although several mutants with altered vacuole morphology have been characterized in the past, the molecular basis for plant vacuole biogenesis has yet to be fully elucidated. With the aim to identify key factors that are essential for vacuole biogenesis, we performed a forward genetics screen in Arabidopsis thaliana and isolated mutants with altered vacuole morphology. The vacuolar fusion defective 1 (vfd1) mutant shows seedling lethality and defects in central vacuole formation. VFD1 encodes FYVE1, a Fab1, YOTB, Vac1 and EEA1 (FYVE)-domain containing protein that has been implicated in intracellular trafficking. FYVE1 localizes on late endosomes and interacts with SH3-domain-containing proteins. Mutants of FYVE1 are defective in ubiquitin-mediated protein degradation, protein secretion and autophagy. Altogether, our results show that FYVE1 is essential for plant growth and development and place FYVE1 as a key regulator of intracellular trafficking and vacuole biogenesis.

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