Activation et régulation des complexes des récepteurs de signalisation membranaires qui contrôlent – SICOPID

Double mutants phenotyping, in vitro pull down, co-immunoprecipitation, phosphoproteomics

Here, we identified that MAKR2 directly interacts with the receptor kinase TMK1 to regulate root gravitropism. We analyzed MAKR2 expression pattern, gain and loss of function phenotypes and interaction with TMK1. In particular, during the reporting period, we demonstrated the direct interaction between MAKR2 and TMK1 kinase domain using in vitro as well as in vivo experiments. We further showed that TMK1 phosphorylates MAKR2 likely to regulate its plasma membrane targeting in response to auxin.

We will now test the effect of TMK1-regulated phosphorylation on MAKR2 function, notably its subcellular localization and membrane interactions. We also worked on MAKR3, another member of the same family of RK inhibitor. We isolated gain and loss of function mutant but we haven’t found its cognate receptor yet, which will be our focus for the rest of the project.

We manuscript relating these findings is currently in revision