Fig. 9

Gene structure, transcript complexity, and expression of the fbrs gene during zebrafish development and in the juvenile brain. (A) Schematic presentation of the 20.5 kb long fbrs genomic region on chromosome 12 (not to scale). Exons are shown as bars. Arrows show TSSs identified either in this study (blue) or annotated based on RNASeq data (purple). (B) Schematic presentation of structure of fbrs transcript identified in this study. Structures of RNASeq transcripts transcribed from alternative TSSs are shown in purple. RNASeq transcript IDs are shown in Table S5. Noncoding and coding exons are depicted as open and filled bars, respectively. (C) RT-PCR analysis of fbrs expression during zebrafish development. Primers amplifying the full-length transcripts were used for analysis. The second faint bands are reverse transcriptase template switching artifacts. (D) Partial DNA sequence of alternatively spliced exon 12. Position of alternative 3′ acceptor splice site is highlighted in orange. Constitutive splice site is underlined. Deleted amino acids are shown in red. (E–J) Whole mount in situ hybridization analysis of fbrs transcript expression in wild-type embryos at different developmental stages, from 1-somite (10.3 hr) to long-pec (48 hr) stages. Arrows point to expression in Kupffer’s vesicle. (L–O) Expression of fbrs mRNA in juvenile brain. Transverse sections were made at the levels indicated by the vertical lines in (K). Abbreviations used to label areas in brain sections can be found in Table S1. ID, identifier; RNASeq, RNA sequencing; RT-PCR, reverse transcription-polymerase chain reaction; TSS, transcription start site.