Evolution and roles of cytokinin genes in angiosperms 2: Do ancient CKXs play housekeeping roles while non-ancient CKXs play regulatory roles?

ABSTRACT: Cytokinin oxidase/dehydrogenase (CKX) is a key enzyme responsible for the degradation of endogenous cytokinins. However, the origins and roles of CKX genes in angiosperm evolution remain unclear. Based on comprehensive bioinformatic and transgenic plant analyses, we demonstrate that the CKXs of land plants most likely originated from an ancient chlamydial endosymbiont during primary endosymbiosis. We refer to the CKXs retaining evolutionarily ancient characteristics as "ancient CKXs" and those that have expanded and functionally diverged in angiosperms as "non-ancient CKXs". We show that the expression of some non-ancient CKXs is rapidly inducible within 15 min upon the dehydration of Arabidopsis, while the ancient CKX (AtCKX7)

SUBMITTER: Wang X 

PROVIDER: S-EPMC7049301 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature