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

Download
  1. Get@NRC: UBC13, an E2 enzyme for Lys63-linked ubiquitination, functions in root development by affecting auxin signaling and Aux/IAA protein stability (Opens in a new window)
DOIResolve DOI: http://doi.org/10.1111/tpj.12644
AuthorSearch for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for: ; Search for:
TypeArticle
Journal titleThe Plant Journal
ISSN0960-7412
Volume80
Issue3
Pages424436; # of pages: 13
SubjectArabidopsis ; UBC13; Lys63-linked; protein ubiquitination; root development; auxin signaling
AbstractUnlike conventional lysine (K) 48–linked polyubiquitination, K63-linked polyubiquitination plays signaling roles in yeast and animals. Thus far, UBC13 is the only known ubiquitin-conjugating enzyme (E2) specialized in K63-linked polyubiquitination. Previous identification of Arabidopsis genes encoding UBC13 as well as its interacting partner UEV1 indicates that the UBC13-mediated ubiquitination pathway is conserved in plants; however, little is known about functions and signaling mediated through K63-linked polyubiquitination in plants. To address the functions of UBC13-mediated ubiquitination in plants, we created Arabidopsis ubc13 null mutant lines in which the two UBC13 genes were disrupted. The double mutant displayed altered root development, including shorter primary root, fewer lateral roots and only a few short root hairs in comparison with the wild type and single mutant plants, indicating that UBC13 activity is critical for all major aspects of root development. The double mutant plants were insensitive to auxin treatments, suggesting that the strong root phenotypes do not simply result from a reduced level of auxin. Instead, the ubc13 mutant had a reduced auxin response, as indicated by the expression of an auxin-responsive DR5 promoter-GFP. Furthermore, both the enzymatic activity and protein level of an AXR3/IAA17-GUS reporter were greatly increased in the ubc13 mutant, whereas the induction of many auxin-responsive genes was suppressed. Collectively, these results suggest that Aux/IAA proteins accumulate in the ubc13 mutant, resulting in a reduced auxin response and defective root development. Hence, this study provides possible mechanistic links between UBC13-mediated protein ubiquitination, root development and auxin signaling.
Publication date
LanguageEnglish
AffiliationAquatic and Crop Resource Development; National Research Council Canada
Peer reviewedYes
NPARC number21275436
Export citationExport as RIS
Report a correctionReport a correction
Record identifier75a5f45d-2884-4ccb-a7be-5250b935a474
Record created2015-07-13
Record modified2016-05-09
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)