Summary of sequenced TRPC1 transcripts. (a) Results from long PCR and TOPO sub-cloning followed by direct DNA sequencing. Messenger RNA was from HEK 293 cells (i), human brain (ii), human saphenous vein (iii), and human aorta (iv). The numbers in the boxes indicate the exon numbers (5'-3', left to right). # indicates the Δ8,9 transcript studied in the functional assays of Figure 6. Grey shading indicates open reading frames (i.e. all but one shows a PTC). (b) Schematic showing the relationship between 13 primary exons of the transcript (tr) and the TRPC1 protein (pr) from amino (N) to carboxy (C) terminus and showing the transmembrane-spanning segments (S1-S6) and the ion pore region (P).