Formin proteins: a domain-based approach.

Henry N Higgs

doi:10.1016/j.tibs.2005.04.014

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Formin proteins: a domain-based approach.

Henry N Higgs

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Abstract

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.

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Actins Animals Carrier Proteins Contractile Proteins Fetal Proteins Formins Humans Microfilament Proteins Models, Molecular Nuclear Proteins Profilins Protein Structure, Tertiary Sequence Homology, Amino Acid rho GTP-Binding Proteins Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.Review

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Henry N Higgs. 2005. Formin proteins: a domain-based approach.. https://doi.org/10.1016/j.tibs.2005.04.014

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