REF-2 was first detected weakly in all 12 P cells just before P-cell migration. REF-2 was present in all P cells as migration occurred and remained in both P cell daughters after division in the ventral cord. This is also the point at which anti-REF-2 staining was strongest. REF-2 then disappears in the Pn.a cell lineage. REF-2 also disappears from the Pn.p cells, although it does so at different rates in different Pn.p cells. REF-2 is present for the longest time in the six unfused Pn.p cells P(3-8).p. REF-2 is also present in P1.p and P2.p shortly after those cells fuse with
hyp7, although REF-2 decreases to an undetectable level soon after. REF-2 disappears most rapidly in P(9-11).p, with REF-2 being detectable in only some worms around the time of Pn.p cell fusion. In summary, REF-2 protein levels decrease around the time of Pn.p cell fusion, although they do so less quickly in the cells that remain unfused. REF-2 protein was also detected in the nuclei of the B and Y cells in the tail region during L1.