Drosophila myosin-XX functions as an actin-binding protein to facilitate the interaction between Zyx102 and actin

Biochemistry. 2014 Jan 21;53(2):350-60. doi: 10.1021/bi401236c. Epub 2014 Jan 9.


The class XX myosin is a member of the diverse myosin superfamily and exists in insects and several lower invertebrates. DmMyo20, the class XX myosin in Drosophila, is encoded by dachs, which functions as a crucial downstream component of the Fat signaling pathway, influencing growth, affinity, and gene expression during development. Sequence analysis shows that DmMyo20 contains a unique N-terminal extension, the motor domain, followed by one IQ motif, and a C-terminal tail. To investigate the biochemical properties of DmMyo20, we expressed several DmMyo20 truncated constructs containing the motor domain in the baculovirus/Sf9 system. We found that the motor domain of DmMyo20 had neither ATPase activity nor the ability to bind to ATP, suggesting that DmMyo20 does not function as a molecular motor. We found that the motor domain of DmMyo20 could specifically bind to actin filaments in an ATP-independent manner and enhance the interaction between actin filaments and Zyx102, a downstream component of DmMyo20 in the Fat signaling pathway. These results suggest that DmMyo20 functions as a scaffold protein, but not as a molecular motor, in a signaling pathway controlling cell differentiation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / chemistry
  • Actins / metabolism*
  • Animals
  • Cloning, Molecular
  • Drosophila Proteins / chemistry
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / metabolism*
  • Microfilament Proteins / chemistry
  • Microfilament Proteins / genetics
  • Microfilament Proteins / metabolism*
  • Myosins / chemistry
  • Myosins / genetics
  • Myosins / metabolism*
  • Zyxin / chemistry
  • Zyxin / metabolism*


  • Actins
  • Drosophila Proteins
  • Microfilament Proteins
  • Zyx protein, Drosophila
  • Zyxin
  • Myosins