Phosphorylation status of Bβ subunit acts as a switch to regulate the function of phosphatase PP2A in ethylene-mediated root growth inhibition.

ABSTRACT: The various combinations and regulations of different subunits of phosphatase PP2A holoenzymes underlie their functional complexity and importance. However, molecular mechanisms governing the assembly of PP2A complex in response to external or internal signals remain largely unknown, especially in Arabidopsis thaliana. We found that the phosphorylation status of Bβ of PP2A acts as a switch to regulate the activity of PP2A. In the absence of ethylene, phosphorylated Bβ leads to an inactivation of PP2A; the substrate EIR1 remains to be phosphorylated, preventing the EIR1-mediated auxin transport in epidermis, leading to normal root growth. Upon ethylene treatment, the dephosphorylated Bβ mediates the formation of the A2-C4-Bβ protein complex to activate PP2A, resulting in the dephosphorylati

SUBMITTER: Shao Z 

PROVIDER: S-EPMC9828452 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature