Moesin

Membrane-organizing extension spike protein

Gene: maps to Xq11.2-q12 and contains 12 exons distributed over more than 30 kb (Wilgenbus K.K. et al., 1994).
mRNA: size: ~4.2 kb.
Protein: a 577-amino acids protein containing no apparent signal peptide or transmembrane domain. It was first identified in bovines as a candidate receptor for heparin or heparan sulfate in the interaction of basement membrane heparan sulfate and cells (Lankes W. et al., 1988). Moesin exhibits a significant homology of sequence to a family of proteins (ezrin, protein 4.1, talin, radixin, and merlin) localized to the submembranous cytoskeleton. Moesin is widely expressed in different tissues in cells, where it is localized to filopodia and other membranous protrusions that are important for cell-cell recognition and signaling and for cell movement.

Cell lines:
- In a panel of eight breast carcinoma cell lines, moesin protein was found to be overexpressed in ER-negative breast carcinoma cell lines but absent from ER-positive breast carcinomas cells (Carmeci C. et al., 1998).

Tumors:
- Moesin mRNA was examined in a panel of 29 primary breast carcinomas with semi-quantitative RT-PCR. Moesin expression was found to be decreased significantly in ER-positive compared with ER-negative tumors (P < .01) (Carmeci C. et al., 1998).

Carmeci C. et al. (1998) Moesin expression is associated with the estrogen receptor-negative breast cancer phenotype. Surgery 124, 211-217.
Lankes W.T. et al. (1988) A heparin-binding protein involved in inhibition of smooth-muscle cell proliferation. Biochem. J. 251, 831-842.
Lankes W.T. and Furthmayr H. (1991) Moesin: a member of the protein 4.1-talin-ezrin family of proteins. Proc. Natl. Acad. Sci. USA 88, 8297-8301.
Wilgenbus K.K. et al. (1994) Structure and localization on the X chromosome of the gene coding for the human filopodial protein moesin (MSN). Genomics 19, 326-333.