Figure 1. Sequence Analysis and Expression Pattern of the ocr Gene Family. (A) Alignment of the four predicted C. elegans OCR proteins. Amino acid sequences are based on sequencing of RT-PCR-generated cDNAs (
ocr-1 and
ocr-2) or on refinement of Genefinder predictions (
ocr-3 and
ocr-4). Identical residues are shaded black; similar residues are shaded gray. Solid lines denote predicted transmembrane domains, and dashed lines denote ankyrin repeats. OSM-9 is 937 amino acids long; its extreme C terminus is not shown.(B) Dendrogram of the TRPV subfamily of TRP-related ion channels. Sequences were aligned using the ClustalW alignment program (Thompson et al., 1994), and the dendrogram was constructed using Phylip software. Mammalian TRPV5 and TRPV6 (ECaC) fall on the same branch as the other mammalian TRPV channels.(C-G) Expression patterns of the ocr genes. Translational GFP fusions were constructed for each of the four ocr genes; each fusion includes the first 68-100 amino acids of the OCR protein. (D) OCR-1::GFP is expressed in the amphid sensory neurons AWA and ADL, indicated by arrows. The animal shown is mosaic, so only the right ADL neuron (ADLR) and left AWA neuron (AWAL) are visible. (E) OCR-2::GFP is expressed in AWA, ADL, ASH, indicated by arrows, as well as ADF and the phasmid neurons PHA and PHB (data not shown). With this transgene, AWA expression is weak compared to ASH and ADL. (F) OCR-3::GFP is expressed in the rectal gland cells, indicated by arrows. (G) OCR-4::GFP is expressed in the OLQ neurons; the OLQ cell bodies are indicated by arrows. The intersection of these expression patterns with that of
osm-9 is represented in the Venn diagram in (C). Scale bar, 30 μm.