HypTABLE 1: Most hypodermal cells are syncytial.
ahyp 6 fuses with hyp 7 during mid-L3 stage (Yochem et al., 1998).
bIn adult hermaphrodite, hyp 7 syncytium contains 139 nuclei. Twenty-three of these are fused embryonically (including hyp 13) and 116 are added postembryonically. Of the nuclei post-embryonically added to hyp 7, 98 derive from seam blast cell divisions (H, V and T lineages), 12 derive from P lineages (including hyp 12) and 6 derive from hyp 6. In the adult male, hyp 7 contains 144 nuclei (Shemer and Podbilewicz, 2000).
chyp 8 - 11 are arranged similarly between the sexes until mid-L4 stage. In males, after mid-L4, hyp 8 fuses with hyp 11, followed by fusion with hyp 9 and finally with hyp 10 generating a syncytium with five nuclei (Nguyen et al., 1999).
dVentral hypodermal cell or preanal hypodermis (P12pa) (Sulston and Horvitz 1977) eventually fuses with hyp 7 (Hedgecock and White, 1985).
eSisters of the T cells (ABpl/rappppa) are located posterior to the anus (see cells 22 and 23 in HypFIG 2) and are present in males until very late L4 when they fuse with hyp 7 (Nguyen et al, 1999). In hermaphrodites, they fuse to generate the hyp 7 syncytium along with 21 other cells during elongation stage.
fLeft and right cell groups. During embryonic and larval life they are unfused and act as stem cells. Late in L4 stage H0-H15, post-embryonically derived seam cells on each side undergo homotypic fusion to form the seam syncytia of adults.
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