Formin, protein diaphanous homologue 1 (IPR027653)

Short name: Formin_Diaph1

Overlapping homologous superfamilies


Family relationships



Protein diaphanous homologue 1 (Dia1) belongs to the formin homology family, Diaphanous subfamily (also known as the Diaphanous-related formins, Drfs). In addition to the FH1 and FH2 domains, Drfs contain an N-terminal GTPase-binding domain (mDiaN) and a C-terminal Diaphanous-autoregulatory domain (DAD).

Dia1 contains the N-terminal RhoA-binding domain (RBD) followed by a four armadillo-repeats containing Diaphanous inhibitory domain (DID) that binds the C-terminal Diaphanous autoregulatory domain (DAD) [PMID: 18572016, PMID: 16292343]. Dia1 nucleates actin filaments and regulate actin polymerisation and depolymerisation. The activities of Dia1 is regulated by an autoinhibitory interaction between DAD domain and the GBD/FH3 domain. This autoinhibition is released upon competitive binding of an activated GTPase. The release of DAD allows the FH2 domain to then nucleate and elongate nonbranched actin filaments [PMID: 16292343]. Dia1 couples Rho and Src tyrosine kinase during signaling and the regulation of actin dynamics [PMID: 10678165].

GO terms

Biological Process

GO:0007015 actin filament organization
GO:0030041 actin filament polymerization

Molecular Function

GO:0017048 Rho GTPase binding
GO:0003779 actin binding

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.