The ERM actin-binding proteins

The ERM (Ezrin, Radixin, Moesin) Actin-Binding Proteins
A group of proteins including Ezrin, Radixin, Moesin, NF2-tumour suppressor (also known as Merlin), many of which are actin-binding proteins. Some members of this group have an unusual ability to bind to discriminate between iso-forms of actin binding b- but not a-F-actin (Hirao et al, 1996). In ezrin the actin binding region has been found to be contained in the C-terminus and similar regions are present in moesin, radixin, but not in merlin (Turunen et al, 1989, 1994).
		Structure of the ERM family.
A trick of the tail? The actin-binding region of ERM proteins reside in the tail. Like vinculin, this actin-binding region is "hidden" in the inactive state. The actin-binding region has been localized to the last 34 amino-acids in the sequence of human ezrin (Turunen et al, 1994; Smith et al, 2003)

Regulation by PIP₂. Like many actin-binding proteins, especially those with a cellular distribution close to the membrane, the ERM group are regulated by phosphoinositide lipids.
Binding Partners
Regulation by Phosphorylation Ezrin is a substrate for the Lck tyrosine kinase (Autero et al, 2003).

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