Casein kinase II promotes target silencing by miRISC through direct phosphorylation of the DEAD-box RNA helicase CGH-1

Amelia F. Alessi, Vishal Khivansara, Ting Han, Mallory A. Freeberg, James J. Moresco, Patricia G. Tu, Eric Montoye, John R. Yates, Xantha Karp, John K. Kim

Research output: Contribution to journalArticle

6 Scopus citations


MicroRNAs (miRNAs) play essential, conserved roles in diverse developmental processes through association with the miRNAinduced silencing complex (miRISC). Whereas fundamental insights into the mechanistic framework of miRNA biogenesis and target gene silencing have been established, posttranslational modifications that affect miRISC function are less well understood. Here we report that the conserved serine/threonine kinase, casein kinase II (CK2), promotes miRISC function in Caenorhabditis elegans. CK2 inactivation results in developmental defects that phenocopy loss of miRISC cofactors and enhances the loss of miRNA function in diverse cellular contexts. Whereas CK2 is dispensable for miRNA biogenesis and the stability of miRISC cofactors, it is required for efficient miRISC target mRNA binding and silencing. Importantly, we identify the conserved DEAD-box RNA helicase, CGH-1/DDX6, as a key CK2 substrate within miRISC and demonstrate phosphorylation of a conserved N-terminal serine is required for CGH-1 function in the miRNA pathway.

Original languageEnglish (US)
Pages (from-to)E7213-E7222
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number52
StatePublished - Dec 29 2015
Externally publishedYes



  • Casein kinase II
  • CGH-1
  • MicroRNA
  • MiRISC
  • Phosphorylation

ASJC Scopus subject areas

  • General

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