Neuronal SH-SY5Y cells use the C- XXXX promoter coupled with exon 78 skipping and display multiple patterns of alternative splicing including two intronic insertion events.

@entity1032 @entity1555 @entity4714 @entity6350 @entity2057
UNASSIGNED: @entity1555 ( @entity1555 ) is a progressive @entity2057 caused by mutations in the @entity4714 gene. One-third of @entity1555 cases are complicated by @entity1032 . Here, we used reverse transcription PCR to analyze the pattern of @entity4714 transcripts in neuronal SH-SY5Y cells. Among the three alternative promoters/first exons at the 5'-end, only transcripts containing the brain cortex-specific C1 exon could be amplified. The C-transcript appeared as two products: a major product of the expected size and a minor larger product that contained the cryptic exon 1a between exons @entity6350 . At the 3'-end there was complete exon 78 skipping. Together, these findings indicate that SH-SY5Y cells have neuron-specific characteristics with regard to both promoter activation and alternative splicing. We also revealed partial skipping of exons 9 and 71. Four amplified products were obtained from a fragment covering exons 36-41: a strong expected product, two weak products lacking either exon 37 or exon 38, and a second strong larger product with a 568-bp insertion between exons 40 and 41. The inserted sequence matched the 3'-end of intron 40 perfectly. We concluded that a cryptic splice site was activated in SH-SY5Y cells to create the novel, unusually large, exon 41e (751  bp). In total, we identified seven alternative splicing events in neuronal SH-SY5Y cells, and calculated that 32 @entity4714 transcripts could be produced. Our results may provide clues in the analysis of transcriptype-phenotype correlations as regards @entity1032 in @entity1555 .
