Nestin, a type VI intermediate filament (IF) protein, is predominantly expressed in neurogenic and myogenic stem cells. We previously identified the first isoform of nestin, Nes-S, in rat DRG neurons. In this study, we report a previously unidentified nestin isoform, Nes-SÄ₁₀₇₋₂₅₄, that is expressed in lower levels in DRG neurons of adult rats. The 29-kD Nes-SÄ₁₀₇₋₂₅₄ is identical to Nes-S, except that an additional region is removed in its rod domain. Nes-SÄ₁₀₇₋₂₅₄ is assembly compromised and forms aggregates. Unlike nestin and Nes-S, Nes-SÄ₁₀₇₋₂₅₄ does not exert cytoprotective effect. Furthermore, elevated caspase-3 activation was observed in HEK293T cells expressing the EGFP-Nes-SÄ₁₀₇₋₂₅₄ protein. Taken together, Nes-SÄ₁₀₇₋₂₅₄ is a rod domain-truncated isoform of nestin that is susceptible to form cytotoxic aggregates.
Alternative Splicing Animals