Expr1926

In C. elegans embryos, H1.X::GFP expression starts with the 30-cell stage. The most prominent structures labeled with both antibodies as well as with H1.X::GFP in transgenic animals are the marginal cells and the tonofilaments therein. The signal appears in all larval stages and in adult C. elegans. No further nuclear or cytoplasmic signal appears besides the labeling of all nuclear lamina caused by the anti-lamin crossreactivity of H1.X-11. This result is confirmed by independent antibody labeling with H1.X-101. In these preparations no nuclear signal appeared in the nuclei of the marginal cells, although the cytoplasm of some head neurons was stained.

Expr13980

In males, DDO-3::mCherry was localized in the excretory pore cell, head tip cells, hypodermal cells, seminal vesicle cells, tail cells, and spicule cells. By contrast, DDO-3::mCherry was also localized in the tail fan from the adult stage, suggesting that DDO-3 is secreted in a SP-dependent manner from the cells where it is produced and transferred to the tail fan. Interestingly, DDO-3::mCherry was localized in vesicle-like structures in the seminal vesicle, where spermatids are stored until ejaculation. Because the seminal vesicle is composed of 20 secretory cells, we presumed that DDO-3 was secreted from the seminal vesicle into the seminal fluid and transferred to the hermaphrodite during mating. To test this possibility, we examined the uteri of hermaphrodites just after mating with transgenic males carrying the ddo-3::mCherry reporter gene. DDO-3::mCherry was dispersed throughout the uterus, suggesting that DDO-3 is a seminal fluid protein. Taken together, these results are consistent with the idea that DDO-3 is secreted from the seminal vesicle into the seminal fluid in a SP-dependent manner, and then transferred to the hermaphrodite uterus through mating. This fusion protein was also present in coelomocytes of males. During larval stages L1 and L2, localization of DDO-3::mCherry outside coelomocytes was limited to the excretory pore cell, implying that DDO-3 expressed in excretory pore cells is secreted into the body fluid. Indeed, at least in the adult stage, DDO-3::mCherry in excretory pore cells was localized to vesicle-like structures.

Expr710

Staining of large nuclei localized alongside intestine, posteriorly of the pharyngo-intestinal valve and anteriorly of the anus. pPD26pgp3.BP strains are detectable in embryonic intestinal cells. pPD26pgp1.X stains with low intensity. Most uniform staining seen in early larval stages. The fraction of L3 and L4 and adult animals that are stained is smaller and staining is of less intensity. Nuclei of anterior-most ring of four cells and of the posterior four-six cells are usually more heavily stained than nuclei of other cells.

Expr705

Pattern very similar to NHR-2 protein. Fusion protein is not seen prior to 16-cell stage. At the 16 to 20-cell stage all cells express except P4 and D. Expression becomes restricted mirroring that for NHR-2 and is ultimately observed in 2-4 cells in head region before disappearing entirely by early comma stage. NHR-2/beta-gal immunostained with anti-beta-gal Ab. 24-cell stage every nuclei stained except P4 and D. 50-cell: many posterior, internal cells do not stain. 500 cell stage 3 cells in presumptive head region stain. X-gal staining same as above.

Expr1443

At 2-cell embryo, MIX-1 protein can be seen in AB, but not in P1. After mitosis, MIX-1 staining becomes more diffuse and less intense, only to increase in intensity just prior to the next mitosis. This apparent oscillation in MIX-1 protein levels is obscured by the accumulation of MIX-1 protein in the interphase nuclei of embryos (~30-cell stage) undergoing rapid cell divisions. However, at a time after most embryonic cell divisions have occurred, cell cycle regulationof MIX-1 becomes noticeable once again. Mitotic cells exhibitintense MIX-1 staining, and interphase cells exhibit weaker X chromosomespecific staining.

Expr1837

Expression of eff-1p::gfp was silent through the first third of embryogenesis, first appearing about 230 min after first cleavage in a subset of epidermal precursor cells. Over the next 3 hr, these and additional fluorescent cells were observed to migrate over the ventral and dorsal surfaces of the embryo, and the majority of GFP-positive cells fused to form the hyp6 and hyp7 syncytia. As elongation progressed, GFP was also expressed in a pair of cells that fused to form the binucleate "tail spike" . After hatching, eff-1p::gfp expression persisted in large epidermal syncytia through adulthood. Mononucleated epidermal cells-including the seam cells and the VPCs-remained nonfluorescent until shortly before undergoing larval fusion events. More specifically, GFP was seen in (1) nonstem daughters of the seam cells shortly before they fused into hyp7; (2) vulval cells invaginating to form toroids during morphogenesis; and (3) the rays and fan of the adult male tail. Expression was also seen in nonepidermal organs known to contain syncytia, including the pharynx and uterus. Interestingly, a few cells that express eff-1p::gfp have never been observed to fuse, such as some ventral epidermal precursors in the embryo and several neurons.

Expr15140

HIS-72 and HIS-74 are visible on the condensed chromatin in the mitotic, transition, and pachytene zones. The signal of both proteins is depleted from one region of the chromatin in pachytene nuclei, as previously noted for HIS-72 (Ooi et al. 2006). Both proteins are depleted from the X chromosomes in these cells. During diakinesis, both HIS-72 and HIS-74 remain chromatin associated, but there are also high levels of the nonchromatin-associated protein in the nucleoplasm, obscuring the chromosomal GFP signal, as previously shown for HIS-72 (Ooi et al. 2006). The similarities of expression patterns and chroma- tin association suggest that the broad chromosomal incorporation in germ cells is similar for both proteins.

Expr15139

HIS-72 and HIS-74 are visible on the condensed chromatin in the mitotic, transition, and pachytene zones. The signal of both proteins is depleted from one region of the chromatin in pachytene nuclei, as previously noted for HIS-72 (Ooi et al. 2006). Both proteins are depleted from the X chromosomes in these cells. During diakinesis, both HIS-72 and HIS-74 remain chromatin associated, but there are also high levels of the nonchromatin-associated protein in the nucleoplasm, obscuring the chromosomal GFP signal, as previously shown for HIS-72 (Ooi et al. 2006). The similarities of expression patterns and chroma- tin association suggest that the broad chromosomal incorporation in germ cells is similar for both proteins.

Expr1578

In adult hermaphrodites carrying either lag-2 5'::lacZ or lag-2::lacZ(intra), beta-galactosidase was observed in the DTC. In adult hermaphrodites carrying lag-2 5'::lacZ, expression was observed exclusively in the DTC nuclei. Beta-galactosidase was found in 62% (30/48) of the DTCs examined in lag-2 5'::lacZ animals, but it was not observed in the germ line or in any non-gonadal cells of these hermaphrodites. Similarly, in adult hermaphrodites carrying lag-2::lacZ(intra), beta-galactosidase was observed in 100% (42/42) of the DTCs examined. In addition to the consistent DTC staining of lag-2::lacZ(intra) animals, there are beta-galactosidase observed within the germ line of 36% (15/42) of the gonads. This germline staining appeared to extend some distance from the distal tip cell. This germline staining was unexpected. LAG-2:: beta-gal(intra) is predicted to have beta-galactosidase on the intracellular side of the fusion protein, which should reside within the cytoplasm of the distal tip cell. Some variable staining was also seen outside the gonad of lag-2::lacZ(intra) animals: a single uncharacterized cell stained positively with X-gal within the head of 2/21 animals, a few cells were positive in the pharynx of 1/21 animals, and a few uncharacterized cells were positive in the tail of 1/21 animals.

Expr15106

SUP-46 is present in the nucleus, cytoplasm, and multiple RNA granules.SUP-46 was expressed ubiquitously in germline and somatic cells. In the germline, SUP-46 was cytoplasmic in mitotic cells in the distal region, and nuclear in the non-dividing cells of the distal, transition, and meiotic zones. Within germ nuclei, SUP-46 was present diffusely, and in granules associated with active chromatin, marked by H3K4me2, but not the inactive X chromosome marked by H3K9me2. Just before ovulation, SUP-46 exited the nucleus and accumulated in the cytoplasm of the meiotic '-1' oocyte (position relative to spermatheca). Similarly, during spermatogenesis SUP-46 was nuclear and chromatin associated during spermatogenesis, but then accumulated in the sperm anucleate meiotic residual body, which captures spermatocyte cytoplasm following completion of meiosis. During oogenesis in the diakinesis region, in addition to localizing to chromatin, SUP-46 also accumulated in the nucleolus (until nucleolar breakdown in the '-2' to '-1' oocyte). In the embryo, SUP-46 was primarily nuclear in non-dividing cells and cytoplasmic in dividing cells. In P1 and P2, which ultimately give rise to the germline during larval development, SUP-46 also accumulated in cytoplasmic granules that were reminiscent of P (germ) granules. Immunolocalization of the constitutive P granule protein PGL-1 confirmed that SUP-46 is present in P granules in the embryo, but not in the adult (gonad).