Characterization of multiple nestin isoforms in the goldfish brain

Nestin is an intermediate filament protein involved in neurogenesis in fish, mice, and humans. In this study we used rapid amplification of cDNA ends PCR to isolate goldfish nestin (nes). PCR analysis and sequencing revealed three different nes transcripts of 4003, 2446, and 2126 nucleotides, which are predicted to generate proteins of 860, 274, and 344 amino acids in length. Sequence analysis suggests that these nes transcripts are likely a result of alternative splicing. We next applied a multiple-antigenic peptide strategy to generate a goldfish-specific nestin antibody. Western blotting with this antibody together with mass spectrometry verified the presence of major nestin protein isoforms with differing molecular weights (~ 70, 40 and 30 kDa). We further examined expression patterns of these nestin protein isoforms in different parts of the goldfish brain and pituitary and found the telencephalon to express all three isoforms at a distinct level and abundance. We report that multiple nestin isoforms are present indicating another level of complexity for the regulation of intermediate filaments in comparison to mammals. Studying the differential roles and regulation of these nestins could lead to a better understanding of cellular remodeling during neurogenesis and the unparalleled regenerative abilities after damage in the teleost CNS.