Figure 5  Alternative splicing of the human TACC1 gene. (A): Seven splice variants have been identified for human TACC1 (A-F and S). We have also identified additional splice variants (G-I) from database analysis and rt-PCR analysis of human brain RNA. (B): Alternative splicing of TACC1 in the human brain. rt-PCR analysis confirms splicing of the untranslated exon 1a to exon 1, with retention of the originally defined start methionine (GB:NP_006274) (Variant A*, lanes 1 and 3). Exon 1a also splices to exon 2, removing the L-Sm7 binding motif (variant I, lanes 3,12 and 13). Variants that functionally delete exons 2 and/or 3, such as variant C (lane 15) also remove the predicted nuclear localization signals, and the binding domains for GAS41 and PCTAIRE2BP. These variants would retain the TACC domain, and therefore the potential to bind to ch-TOG and Aurora A kinase in the centrosome. Lane 1: EF/X1R, Lane 2: EF/BX647R, Lane 3: EF/6SPR, Lane 4: EF/1DR, Lane 5, EF/128R, Lane 6 X3F/X1R, Lane 7: X3F/BX647R, Lane 8: X3F/6SPR, Lane 9: X3F/1DR, Lane 10, X3F/128R, Lane 11: 1DF/X1R, Lane 12: 1DF/BX647R, Lane 13: 1DF/6SPR, Lane 14: 1DF/1DR, Lane 15: 1DF/128R, Lane 16: Biorad 1 kb+ Size ladder.