Figure 1. Expression of Slc4a10 in rat.

(A) Structure of rat Slc4a10 gene. P1, P2, and P3 represent the three alternative promoters of rat Slc4a10. Promoter P2 and exon 3 are newly identified in the present study. The gray portion (exons 16–26) encodes the predicited transmembrane domain of NBCn2. # indicate the cassette exons (exons 3, 4, 7, 11, 27, 28) that can be alternatively spliced. (B) 5′-RACE to clone the 5′-UTR of NBCn2 transcripts from adult rat kidney. The reverse primer complimentary to exon 4 (arrow in panel A) was used to amplify the 5′-UTR of MCDL-NBCn2, and the reverse primer complimentary to exon 5 (arrow in panel A) was used to amplify the 5′-UTR of NBCn2. (C) RT-PCR analysis of the expression of NBCn2 transcripts in the brain and kidney of adult rat. Promoter-specific sense primers were used to amplify the NBCn2 transcripts derived from the three different promoters of Slc4a10. The anti-sense primer was the same for all three PCRs. The PCR products were verified by DNA sequencing. H₂O was used as template for the control. (D) Cloning of full-length NBCn2 derived from promoter P2 by nested RT-PCR with rat kidney. (E) Western blotting of the distribution of NBCn2 proteins in cellular fractions of rat kidney homogenate.