mNG::LIN-7, LIN-2::mK2 and mNG::LIN-10 were found to bebroadly expressed in the worm. In L3 larvae, they were prominentlyexpressed in VPCs and neurons, whereas only LIN-7 and LIN-10 weredetectable in the somatic gonad primordium. In the VPCs,endogenous mNG::LIN-7 was strongly cytosolic, frequently found atpunctae, and occasionally localized to basolateral membranes.
Fluorescence microscopy revealed that a TRIM-21::mCherry or TRIM-21::GFP fusion reporter co-localized to the surface of cell corpses with CED-1::GFP and mCherry::CED-6 reporters in C. elegans.
mNG::LIN-7, LIN-2::mK2 and mNG::LIN-10 were found to bebroadly expressed in the worm. In L3 larvae, they were prominentlyexpressed in VPCs and neurons, whereas only LIN-7 and LIN-10 weredetectable in the somatic gonad primordium. In the VPCs,endogenous mNG::LIN-7 was strongly cytosolic, frequently found atpunctae, and occasionally localized to basolateral membranes.
The endogenous lin-28 promoter drives lin-28::GFP expression in neurons and hypodermis, where lin-28 is known to be expressed (Moss et al., 1997). Using spinning disk microscopy we also detected lin-28p::lin-28::GFP expression in Z1 and Z4 cells, which are precursors of somatic gonadal tissues.
TSP-21::GFP is plasma membrane-localized and is expressed in a wide variety of somatic cell types, including the pharynx, intestine and hypodermis starting in embryos after the 100 cell stage and peaking in L1 and L2 larvae. The TSP-21::GFP signal in these tissues decreases in late larval and adult stage animals. TSP-21::GFP is also present at the surface of M lineage cells from the 1-M stage to the 16-M stage. TSP-21::GFP is enriched in the basolateral side of intestinal cells while being absent from their apical sides. In addition, while TSP-21::GFP in the M lineage cells is primarily plasma membrane localized, there is also a significant intracellular distribution of TSP-21::GFP in the M mesoblast.
Expression of mpk-1::gfp was observed in the rectal epithelial cells, including F and U, in 100% of wild type L1 (16/16), L2 (19/19), L3 (15/15), L4 (21/21) and adult (16/16)worms.
lin-31p::cfp and LIN-12::GFP are expressed in multipotent VPCs during larval (L)2 stage and before induction in the L3 stage. lin-31p::cfp expression remains high in VPCs of dauer larvae. LIN-12::GFP remains expressed in VPCs in dauer larvae.