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Title: HECT‐type ubiquitin ligase KAKTUS mediates the proteasome‐dependent degradation of cyclin‐dependent kinase inhibitor KRP2 during trichome morphogenesis in Arabidopsis
SUMMARY

Trichome development is a fascinating model to elaborate the plant cell differentiation and growth processes. A wealth of information has pointed to the contributions of the components associated with cell cycle control and ubiquitin/26S proteasome system (UPS) to trichome morphogenesis, but how these two pathways are connected remains obscure. Here, we report that HECT‐type ubiquitin ligase KAKTUS (KAK) targets the cyclin‐dependent kinase (CDK) inhibitor KRP2 (for kip‐related protein 2) for proteasome‐dependent degradation during trichome branching in Arabidopsis. We show that over‐expression ofKRP2promotes trichome branching and endoreduplication which is similar tokakloss of function mutants. KAK directly interacts with KRP2 and mediates KRP2 degradation. Mutation ofKAKresults in the accumulation of steady‐state KRP2. Consistently, inkak pKRP2:KRP2‐GFPplants, the trichome branching is further induced compared with the single mutant. Taken together, our studies bridge the cell cycle control and UPS pathways during trichome development and underscore the importance of post‐translational control in epidermal differentiation.

 
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Award ID(s):
2425989
PAR ID:
10442170
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
116
Issue:
3
ISSN:
0960-7412
Format(s):
Medium: X Size: p. 871-886
Size(s):
p. 871-886
Sponsoring Org:
National Science Foundation
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