CARF and lymphoma: Interestingly, CARF is the human homolog of Arabidopsis Kip‐related protein 6 (KRP6), a cell cycle inhibitor, sharing conserved phosphorylation sites by CK1.[22] The non‐phosphorylation variant of CARF dramatically inhibits cell proliferation in different lymphoma cell lines and mice xenograft tumor models in vivo, similar to non‐phosphorylation variant of KRP6, indicating that phosphorylation of CARF regulates cell proliferation and lymphoma tumorigenesis.