Figure 3.—

rdy-2 encodes two putative tetraspan proteins. (A, top) Genetic map of chromosome V showing the positions of markers used to map rdy-2. rdy-2(mc39) and rdy-2(mc40) mutations were positioned between a SNP localized in the cosmid T10G3 and the left breakpoint of itDf2, which is defined by the cosmid T03D2. (Middle) Among cosmids in the area, only cosmids C50B8 and F53F4 (boldface type) could rescue the lethality of rdy-2(mc39) larvae (the number of rescuing lines tested for the presence of cosmid DNA by PCR is indicated on the right). (Bottom) Among PCR-generated subfragments of F53F4, only F53F4.6 could rescue the lethality of rdy-2(mc39) larvae. (B) Predicted exon–intron structure of F53F4.6 according to Wormbase version WS157 (top) and actual exon–intron structure of rdy-2 transcripts deduced from RT–PCR experiments using the primers symbolized between both structures (half arrows; S, sense; R, reverse; nucleotides are numbered relative to the first AUG according to WS157). The positions of conserved areas in the C. briggsae F53F4.6 homolog are symbolized by dashed lines. (C) A more detailed description of the molecular lesion corresponding to rdy-2(mc40) (see Figure 2B for symbols). (D) Topology of the long and short RDY-2 proteins as predicted by the software TMHMM version 2.0 (http://www.cbs.dtu.dk/services/TMHMM/); the N-term extension of the long protein is indicated shaded.