Figure 4.

The amino portion of the i3 loop of Htr6 is sufficient to localize Htr7 to cilia. (A) Schematic of chimeric receptors containing portions of Htr6 (black lines) and Htr7 (white lines) fused at the C-terminus to EGFP. TM domains are depicted as boxes. (B–D) Representative images of transiently transfected IMCD cells expressing the indicated chimeric receptors. Left, EGFP fluorescence (green); middle, acetylated α-tubulin (red); right, merged images. Chimeric receptors Htr7[TM5-6Htr6] (B) and Htr7[TM5-V241Htr6] (C) selectively localize to cilia, whereas chimeric receptor Htr7 [V241-TM6Htr6] (D) does not, suggesting that the N-portion of the i3 loop of Htr6 contains ciliary localization sequences. Nuclei are labeled with DRAQ5 (blue). All scale bars, 10 μm.