Journal
PLANT JOURNAL
Volume 115, Issue 5, Pages 1357-1376Publisher
WILEY
DOI: 10.1111/tpj.16324
Keywords
Arabidopsis; auxin; boron deprivation; Dendra2; PIN endocytosis; root growth
Categories
Ask authors/readers for more resources
This study revealed the mechanistic basis of how boron deprivation inhibits root growth in Arabidopsis. Boron deprivation resulted in increased auxin accumulation in roots, which was associated with upregulation of auxin biosynthesis-related genes in shoots. The PIN2/3/4 carriers were found to be involved in root growth inhibition caused by boron deprivation.
The mechanistic basis by which boron (B) deprivation inhibits root growth via the mediation of root apical auxin transport and distribution remains elusive. This study showed that B deprivation repressed root growth of wild-type Arabidopsis seedlings, which was related to higher auxin accumulation (observed with DII-VENUS and DR5-GFP lines) in B-deprived roots. Boron deprivation elevated the auxin content in the root apex, coinciding with upregulation of the expression levels of auxin biosynthesis-related genes (TAA1, YUC3, YUC9, and NIT1) in shoots, but not in root apices. Phenotyping experiments using auxin transport-related mutants revealed that the PIN2/3/4 carriers are involved in root growth inhibition caused by B deprivation. B deprivation not only upregulated the transcriptional levels of PIN2/3/4, but also restrained the endocytosis of PIN2/3/4 carriers (observed with PIN-Dendra2 lines), resulting in elevated protein levels of PIN2/3/4 in the plasma membrane. Overall, these results suggest that B deprivation not only enhances auxin biosynthesis in shoots by elevating the expression levels of auxin biosynthesis-related genes but also promotes the polar auxin transport from shoots to roots by upregulating the gene expression levels of PIN2/3/4, as well as restraining the endocytosis of PIN2/3/4 carriers, ultimately resulting in auxin accumulation in root apices and root growth inhibition.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available