Roles of the UPP during Root Development 42. Rubinsztein DC (2006) The roles of intracellular protein-degradation pathways in neurodegeneration. Nature 443: 780–786. 43. Cecconi F, Di Bartolomeo S, Nardacci R, Fuoco C, Corazzari M, et al. (2007) A novel role for autophagy in neurodevelopment. Autophagy 3: 506–508. 44. Mizushima N (2007) Autophagy: Process and function. Genes Dev 21: 2861– 2873. 45. Moon J, Parry G, Estelle M (2004) The ubiquitin-proteasome pathway and plant development. Plant Cell 16: 3181–3195. 46. Wang S, Kurepa J, Hashimoto T, Smalle JA (2011) Salt stress-induced disassembly of Arabidopsis cortical microtubule arrays involves 26S proteasome- dependent degradation of SPIRAL1. Plant Cell 23: 3412–3427. PLOS ONE | www.plosone.org 8 September 2012 | Volume 7 | Issue 9 | e45673