Formin proteins: a domain-based approach

Trends Biochem Sci. 2005 Jun;30(6):342-53. doi: 10.1016/j.tibs.2005.04.014.


Formin proteins are potent regulators of actin dynamics. Most eukaryotes have multiple formin isoforms, suggesting diverse cellular roles. Formins are modular proteins, containing a series of domains and functional motifs. The Formin homology 2 (FH2) domain binds actin filament barbed ends and moves processively as these barbed ends elongate or depolymerize. The FH1 domain influences FH2 domain function through binding to the actin monomer-binding protein, profilin. Outside of FH1 and FH2, amino acid similarity between formins decreases, suggesting diverse mechanisms for regulation and cellular localization. Some formins are regulated by auto-inhibition through interaction between the diaphanous inhibitory domain (DID) and diaphanous auto-regulatory domain (DAD), and activated by Rho GTPase binding to GTPase-binding domains (GBD). Other formins lack DAD, DID and GBD, and their regulatory mechanisms await elucidation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Actins / metabolism*
  • Animals
  • Carrier Proteins / metabolism
  • Contractile Proteins / metabolism*
  • Fetal Proteins
  • Formins
  • Humans
  • Microfilament Proteins / chemistry
  • Microfilament Proteins / metabolism*
  • Models, Molecular
  • Nuclear Proteins
  • Profilins
  • Protein Structure, Tertiary
  • Sequence Homology, Amino Acid
  • rho GTP-Binding Proteins / metabolism


  • Actins
  • Carrier Proteins
  • Contractile Proteins
  • DIAPH2 protein, human
  • Diap1 protein, mouse
  • Fetal Proteins
  • Formins
  • Microfilament Proteins
  • Nuclear Proteins
  • PFN1 protein, human
  • Profilins
  • rho GTP-Binding Proteins