Arabidopsis thalianaMLK3, a Plant-specific Casein Kinase 1, Negatively Regulates Flowering and Phosphorylates Histone H3 in Vitro.

ABSTRACT: Arabidopsis thaliana MUT9-like kinases (MLKs), a family of the plant-specific casein kinase 1 (CK1), have been implicated collectively in multiple biological processes including flowering. Three of the four MLKs (MLK1/2/4) have been characterized, however, little is known about MLK3, the most divergent member of MLKs. Here, we demonstrated that disruption of MLK3 transcript in mlk3 caused early flowering with retarded leaf growth under long-day conditions. In vitro kinase assay showed the nuclear protein MLK3 phosphorylated histone 3 at threonine 3 (H3T3) and mutation of a conserved residue (K146R) abolished the catalytic activity. Ectopic expression of MLK3 but not MLK3(K146R) rescued the morphological defects of mlk3, indicating that an intact MLK3 is critical for maintaining proper flow

SUBMITTER: Kang J 

PROVIDER: S-EPMC7141126 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature