Analysis of the cloned zebrafish β3 subunit gene. Presentation and labeling as in Figure 1. A) Alignment of cloned human, mouse, rat, and zebrafish β3 amino acid sequences. INT = putative internalization sequence. B) 5' and 3' RLM-RACE PCR and RT-PCR identified a single transcript expressed from the zβ3 locus on zebrafish chromosome 15 (Ensembl). zβ3 has six exons. C) All zβ3 splice sites adhere to GT-AG consensus sequences. D) Schematic diagram of the β3 protein.