Figure 2 LPR-1 functions cellnonautonomously and localizesboth extracellularly and intracellularly. (A) Rescue ability of varioustransgenes expressing GFP-taggedLPR-1 with or without a signal sequence. Bars indicate percentageof transgenic (Tg) (black) or nontransgenic (non-Tg) (white) animals showing normal excretorytube morphology at the L1 stageas assessed by DIC microscopy.***P , 0.0001 compared to nontransgenic siblings (Fisher's exacttest). (B and B') Expression patternof
lpr-1p::LPR-1::SfGFP at 1.5-fold.Duct and pore cells are marked bygrl-2p::mRFP (red). (C and C') Expression pattern of
lpr-1p::ssGFP::LPR-1(25-261) at 1.5-fold. Boxesin (B) and (C) indicate the regionsmagnified in (B') and (C'). (D, D',D'', and D''') Expression pattern oflpr-1p::LPR-1::SfGFP at threefold.(D'') and (D''') show a confocalprojection of the duct and porefrom the same embryo. White arrows indicate fusion protein accumulating in the space betweenthe embryo and the eggshell. (Eand E9) Duct and pore cells aremarked by
grl-2p::mRFP. (F andF9)
lpr-1p::ssGFP::LPR-1(25-261)was expressed in the epidermisand accumulated in the spacebetween the embryo and theeggshell, indicated by white arrows. In an early threefold embryo,
lpr-1p::ssSfGFP::LPR-1(250-261) wasenriched cortically in the duct andpore (marked in red). (G and G')
lpr-1p::GFP::LPR-1(25-261) lackinga signal peptide was restricted inepithelia and not secreted. Whitelines indicate the space betweenthe embryo and the eggshell. (Hand H')
grl-2p::ssGFP::LPR-1(25-261) was only detectably expressedin the duct and pore cells (n = 37).(I and I')
unc-54p::ssGFP::LPR-1(25-261) was not secreted apically fromembryos, but (J and J') accumulated in coelomocytes (cc) in larvae.Bar, 5 uM.