Long Flagella 2 (LF2)

Chlamydomonas reinhardtii has two apically localized flagella that are maintained at an equal and appropriate length. Assembly and maintenance of flagella requires a microtubule-based transport system known as intraflagellar transport (IFT). During IFT, proteins destined for incorporation into or removal from a flagellum are carried along doublet microtubules via IFT particles. Regulation of IFT activity therefore is pivotal in determining the length of a flagellum. Reviewed is our current understanding of the role of IFT and signal transduction pathways in the regulation of flagellar length. Multiple lines of evidence also point to a role for CDK20 in flagellum biosynthesis: Mutants in Chlamydomonas CDK20 disrupt flagellum length control and assembly. LF2 interacts genetically with LF4, which encodes a  MOK subfamily kinase.