Picture from Johnston WL et al. (2006) BMC Biol "The eggshell is required for meiotic fidelity, polar-body extrusion and ...."

Figure 8. MBK-2::GFP and WGA-G colocalize, and chs-1 is required for MBK-2 localization. (A) Wild type expressing MBK-2::GFP, stained for DNA (Hoechst), GFP (MBK-2) or WGA-binding epitopes, in the germline (top row), or in embryos at meiotic metaphase I (middle row) or meiotic anaphase I (bottom row). In embryos, maternal DNA is shown enlarged in box on lower right hand of DNA images. (B) DNA (Hoechst) or WGA-binding epitopes in mbk-2(pk1427) (putative null). (C) chs-1(RNAi) expressing MBK- 2::GFP and stained for DNA (Hoechst), GFP (MBK-2) or WGA-binding epitopes in the germline (top row), or in an early embryo. (D) cej-1+B0280.5(coRNAi) expressing MBK- 2::GFP stained for DNA (Hoechst), GFP (MBK-2) or WGA- binding epitopes in the germline (top row), or in an early embryo. (E) DNA (Hoechst) or chitin in germline of wild type. (A-E) Proximal refers to the region of the germline near the spermatheca. Embryos are at the one-cell stage.

Picture from Johnston WL et al. (2006) BMC Biol "The eggshell is required for meiotic fidelity, polar-body extrusion and ...."

(A) Wild type expressing MBK-2::GFP, stained for DNA (Hoechst), GFP (MBK-2) or WGA-binding epitopes, in the germline (top row), or in embryos at meiotic metaphase I (middle row) or meiotic anaphase I (bottom row). In embryos, maternal DNA is shown enlarged in box on lower right hand of DNA images. Proximal refers to the region of the germline near the spermatheca. Embryos are at the one-cell stage.

Picture from Johnston RJ et al. (2006) Development "An unusual Zn-finger/FH2 domain protein controls a left/right asymmetric ...."

Fig. 3. Rescue, expression, site of action and domain requirements of fozi-1. (A) Rescue of the fozi-1 mutant phenotype. The constructs do not contain the first, non-coding exon of the fozi-1 gene, which is located >7 kb upstream of the ATG-containing second exon (Fig. 2A). The right column indicates rescue of the fozi-1 defect, i.e. suppression of aberrant lim-6 expression in ASER, and the left column indicates suppression of normal lim-6 expression in ASEL fate, caused by ectopic expression of fozi-1. All constructs show similar expression levels and exclusive localization to the nucleus. (B) A representative fozi-1::gfp-expressing animal, showing gfp expression in ASER but not ASEL, and in the two olfactory neurons AWCL and AWCR. Broken lines approximately indicate the head of the worm. The insets show that fozi-1::gfp predominantly localizes to the nucleus. The red 'cyto' marker is dsRed2 protein, expressed under control of the ceh-36 promoter (otIs151 transgene). (C) Three out of four fozi- 1::gfp-expressing transgenic, wild-type lines display varying levels of asymmetric gfp expression in ASER. Circles indicate absent, ASEL alone, ASEL and ASER, and ASER alone, respectively.

Picture from Johnston WL et al. (2010) Curr Biol "Eggshell chitin and chitin-interacting proteins prevent polyspermy in C. ...."

Figure S2 (Related to Figure 2). CBD-1 Localizes around Oocytes in the Proximal Germline "-1" and "-2" refer to oocytes most proximal to the spermatheca and next most proximal, respectively. Depletion of EGG-1 (egg-1(RNAi)) does not prevent CBD-1 localization. Scalebars represent 15 um.

Picture from Johnston RJ et al. (2006) Development "An unusual Zn-finger/FH2 domain protein controls a left/right asymmetric ...."

A representative fozi-1::gfp-expressing animal, showing gfp expression in ASER but not ASEL, and in the two olfactory neurons AWCL and AWCR. Broken lines approximately indicate the head of the worm. The insets show that fozi-1::gfp predominantly localizes to the nucleus. The red cyto' marker is dsRed2 protein, expressed under control of the ceh-36 promoter (otIs151 transgene). (C) Three out of four fozi-1::gfp-expressing transgenic, wild-type lines display varying levels of asymmetric gfp expression in ASER. Circles indicate absent, ASEL alone, ASEL and ASER, and ASER alone, respectively.

Picture from Johnston RJ et al. (2005) Development "A novel C. elegans zinc finger transcription factor, lsy-2, required for the cell ...."

Figure 4. lsy-2 is expressed ubiquitously and localizes to moving speckles in the nucleus. (A) lsy-2prom::gfp and lsy-2::gfp reporter gene constructs used in this study. The gray bar behind the green gfp sequence indicates the heterologous unc-54 3'UTR. (B) lsy-2prom::gfp and lsy-2::gfp reporter gene constructs are ubiquitously expressed at different developmental stages. Nine independent lsy-2::gfp transgenic lines and three independent lsy-2prom::gfp lines show similar expression patterns. (C) lsy-2::gfp is expressed in ASEL and ASER. ASEL and ASER are labeled with the ceh-36prom::rfp transgene otIs151. Note that the rfp reporter is diffusely localized throughout the cytoplasm, whereas the gfp signal is in nuclear speckles. lsy-2::gfp rescues the lsy-2 mutant phenotype (Table 3). (D) lsy-2::gfp is localized to moving nuclear speckles. Individual time frames of a movie, shot with Openlab Software at a time interval of half a second per frame (20 frames total), are displayed. The movie is available upon request.

Picture from Johnston RJ et al. (2005) Proc Natl Acad Sci U S A "MicroRNAs acting in a double-negative feedback loop to control a neuronal cell ...."

ASER- specific cell fate marker.

Picture from Johnston RJ et al. (2005) Proc Natl Acad Sci U S A "MicroRNAs acting in a double-negative feedback loop to control a neuronal cell ...."

Figure 1. Mutations in lsy genes cause a state transition between the ASEL and ASER fates. (A) Gene regulatory factors controlling ASE laterality, as deduced by our previous genetic analysis (3-6). The permissively acting, ASEL/R-expressed genes unc-37/Groucho, lin-49, and ceh-36 (4) are left out for clarity. mir-273 likely acts together with other mir-273-related miRNAs (D. Didiano and O.H., unpublished data), yet throughout this paper, we only show mir-273 for clarity. (B) ASEL- and ASER-specific cell fate markers and their regulation by lsy genes. ASER-specific expression can be observed with a subfragment from the hen-1 promoter (hen-1ASER ::gfp). In all cases, reporter gene expression in ASE was unambiguously determined by using a chromosomally integrated rfp transgene in the genetic background, which is expressed in ASEL/R. Fig. 5, which is published as supporting information on the PNAS web site, shows the quantification of data. (C) Summary of the genetic interactions deduced from B. (D) Early bilateral expression of the ASEL inducer lsy-6 and of the ASER inducer cog-1. Early bilateral expression can also be observed for gcy-6, gcy-7, and lim-6 (Fig. 6, which is published as supporting information on the PNAS web site, shows the quantification of all observations). *, gfp-expressing cells other than ASE, which are out of focus in Right. (E) Even if both ASE neurons are fated to become ASER in class II lsy-6 mutant animals, they initially express both ASEL and ASER markers. See Fig. 6 for quantification of effects.

Picture from Johnston RJ et al. (2005) Proc Natl Acad Sci U S A "MicroRNAs acting in a double-negative feedback loop to control a neuronal cell ...."

ASER- specific cell fate marker.

Picture from Johnston RJ et al. (2005) Proc Natl Acad Sci U S A "MicroRNAs acting in a double-negative feedback loop to control a neuronal cell ...."

ASEL- specific cell fate marker.