UBC13, an E2 enzyme for Lys63‐linked ubiquitination, functions in root development by affecting auxin signaling and Aux/IAA protein stability

• DOI: 10.1111/tpj.12644
• Publication Date: 2014-08-21T07:34:04Z
• Authors: Rui Wen; Sheng Wang; Daoquan Xiang; Prakash Venglat; Xianzong Shi; Yuepeng Zang; Raju Datla; Wei Xiao; Hong Wang
• Keywords: Ubiquitin-conjugating enzyme; Root hair

Summary Unlike conventional lysine (K) 48–linked polyubiquitination, K63‐linked polyubiquitination plays signaling roles in yeast and animals. Thus far, UBC 13 is the only known ubiquitin‐conjugating enzyme (E2) specialized polyubiquitination. Previous identification of Arabidopsis genes encoding as well its interacting partner UEV 1 indicates that 13‐mediated ubiquitination pathway conserved plants; however, little about functions mediated through plants. To address plants, we created ubc13 null mutant lines which two were disrupted. The double displayed altered root development, including shorter primary root, fewer lateral roots a few short hairs comparison with wild type single indicating activity critical for all major aspects development. plants insensitive to auxin treatments, suggesting strong phenotypes do not simply result from reduced level auxin. Instead, had response, indicated by expression an auxin‐responsive DR 5 promoter‐ GFP . Furthermore, both enzymatic protein AXR 3/ IAA 17‐ GUS reporter greatly increased mutant, whereas induction many was suppressed. Collectively, these results suggest Aux/ proteins accumulate resulting response defective Hence, this study provides possible mechanistic links between ubiquitination, development signaling.