Point mutation in the NF2 gene of HEI-193 human schwannoma cells results in the expression of a merlin isoform with attenuated growth suppressive activity.

Neurofibromatosis type 2 (NF2) is a genetic disorder characterized by the formation of bilateral schwannomas of the eighth cranial nerve. Although the protein product of the NF2 gene (merlin) is a classical tumor suppressor, the mechanism by which merlin suppresses cell proliferation is not fully understood. The availability of isolated tumor cells would facilitate a better understanding of the molecular function of merlin, but primary schwannoma cells obtained from patients grow slowly and do not yield adequate numbers for biochemical analysis.

Prenylation-defective human connexin32 mutants are normally localized and function equivalently to wild-type connexin32 in myelinating Schwann cells.

Mutations in GJB1, the gene encoding the gap junction protein connexin32 (Cx32), cause the X-linked form of Charcot-Marie-Tooth disease, an inherited demyelinating neuropathy. The C terminus of human Cx32 contains a putative prenylation motif that is conserved in Cx32 orthologs. Using [3H]mevalonolactone ([3H]MVA) incorporation, we demonstrated that wild-type human connexin32 can be prenylated in COS7 cells, in contrast to disease-associated mutations that are predicted to disrupt the prenylation motif.

Methods to study protein-protein interactions.

Protein-protein interactions are the underpinnings of a vast number of cellular processes. In recent years, the convergence of biochemistry, cellular, and molecular biology has made available a number of powerful techniques for studying such interactions. These techniques vary in their sensitivity, efficiency, and rapidity, but judicial deployment of a combination of them has proved to be effective and reliable.

Activation of the tumor suppressor merlin modulates its interaction with lipid rafts.

Neurofibromatosis type 2 (NF2) is a genetic disorder characterized by bilateral schwannomas of the eighth cranial nerve. The NF2 tumor suppressor protein, merlin, is related to the ERM (ezrin, radixin, and moesin) family of membrane/F-actin linkers. Merlin resists solubilization by the detergent Triton X-100 (TX-100), a property commonly attributed to association with the cytoskeleton.