The phytohormone auxin controls a myriad of processes in plants, at least in part through its regulation of cell expansion. The "acid growth hypothesis" has been proposed to explain auxin-stimulated cell expansion for five decades, but the mechanism underlying auxin-induced cell wall acidification is poorly characterized. Auxin induces the phosphorylation and activation of the plasma membrane (PM) H+-ATPase that pumps protons into the apoplast, yet how auxin activates its phosphorylation remains elusive. Here, we show that the transmembrane kinase (TMK) auxin signaling proteins interact with PM H+-ATPases and activate their phosphorylation to promote cell wall acidification and hypocotyl cell elongation in Arabidopsis. Auxin induced TMK's interaction with H+-ATPase on the plasma membrane within 1-2 minutes as well as TMK-dependent phosphorylation of the penultimate Thr residue. Genetic, biochemical, and molecular evidence demonstrates that TMKs directly phosphorylate PM H+-ATPase and are required for auxin-induced PM H+-ATPase activation, apoplastic acidification, and cell expansion. Thus, our findings reveal a crucial connection between auxin and PM H+-ATPase activation in regulating apoplastic pH changes and cell expansion via TMK-based cell surface auxin signaling.
[doi:10.25345/C5T25J]
[dataset license: CC0 1.0 Universal (CC0 1.0)]
Keywords: auxin, TMK, cell surface, phosphorylation, cell wall
|
Principal Investigators: (in alphabetical order) |
Yang, zhenbiao, University Of California, Riverside, USA |
| Submitting User: | haiyanzheng |
| Number of Files: | |
| Total Size: | |
| Spectra: | |
| Subscribers: | |
| Owner | Reanalyses | |
|---|---|---|
| Experimental Design | ||
|
Conditions:
|
||
|
Biological Replicates:
|
||
|
Technical Replicates:
|
||
| Identification Results | ||
|
Proteins (Human, Remapped):
|
||
|
Proteins (Reported):
|
||
|
Peptides:
|
||
|
Variant Peptides:
|
||
|
PSMs:
|
||
| Quantification Results | ||
|
Differential Proteins:
|
||
|
Quantified Proteins:
|
||
| Browse Dataset Files | |
|
FTP Download Link (click to copy):
|