Picture from Clark, James F et al. MicroPubl Biol

C. elegans contain three 9 fatty acid desaturases (FADs), fat-5, fat-6, and fat-7, responsible for the initial desaturation step in the synthesis of complex polyunsaturated fatty acids (PUFAs). Production of PUFAs is vital for survival, as simultaneous loss-of-function in all three genes results in synthetic lethality (Brock et al. 2006). Animals containing mutations in any one of the three 9 FADs, fat-5, fat-6, and fat-7, display an increase in body length. fat-5 mutants display a significant increase from 48 hours onward, while fat-6 and fat-7 display a significant increase from 72 hours onward. Since fat-6 and fat-7 mutants have reduced lipid accumulation (Horikawa et al. 2008; Zhang et al. 2013; Clark et al. 2018), these findings on body size suggest that the two phenotypes are not correlated. Consistent with this conclusion, dbl-1 mutants display both decreased body size and lipid accumulation while lon-2 and dbl-1(OE) mutants display increased body size and decreased lipid accumulation at the L4 stage (Clark et al. 2018). Error bars denote SEM, Statistical significance determined via Student's T-test, n.s. not significant, * p<0.05, ** p<.0.01,*** p<0.001. n>25 per strain, repeated in duplicate. Animals were synchronized via an egg lay followed by a timed hatch. Animals were collected and imaged at 25X using a QImaging Retiga EXi camera with QCapture software at each timepoint. Body length was measured by tracing the midline of the animals in ImageJ.

Picture from Oswald , Mackenzi et al. (2020) MicroPubl Biol

Figure 1. Mutations in E2 ubiquitin-conjugating enzyme genes and glr-1 affect spontaneous reversal frequencies differently: A. Spontaneous reversal frequency assays were performed using wild type (WT) C. elegans, alongside strains harboring mutations in glr-1 or in genes that encode the E2 ubiquitin-conjugating enzymes, ubc-6 and ubc-7. Box and whisker plots show the average reversals per minute, bounded by quartiles; the line in each box represents the median of the average reversals per minute for each genotype. N=20 individual animals for all genotypes; significance relative to WT was calculated using the Tukey-Kramer test following a one-way ANOVA (*, p=0.0027 for glr-1; non-significant: p=0.58 for ubc-6; p=0.48 for ubc-7). The data is normally distributed (Shapiro-Wilk test, p=0.86) and groups show equal variance (residuals vs. fitted plot). B. Schematics of E2 ubiquitin-conjugating enzyme genes and glr-1 gene, including the locations of point mutations. Schematics were made using http://wormweb.org/exonintron. C. Crystal structures of the human E2 Ube2j2 (top, with rotated view to show the back side of the protein) and Ube2g2 (bottom, left). Models were made using Pymol. Residues that are mutated are shown in red (Ube2j2, D153; UBC-6, T158) and yellow (Ube2g2, P78, UBC-7, P79). Residue F156 of Ube2j2 is shown in cyan. Alignments of C. elegans UBC-6 and UBC-7 regions of homology, compared to putative orthologs in other eukaryotes. The highlighted residues correspond to those shown in the structures.

Picture from Tsur A et al. (2015) Dev Cell "ULP-2 SUMO Protease Regulates E-Cadherin Recruitment to Adherens ...."

Figure 1. ULP-2 Is Expressed in C. elegans Epidermal Cells and Underlying Neuroblasts and Is Essential for Epidermal Morphogenesis(A) Schematic of the ULP-2::GFP reporter construct generated from the entire ulp-2 genomic locus (WormBase: 173859) (http://www.wormbase.org/species/c_elegans/gene/WBGene00006737#0bc1-9e63dfha84-10); red bar indicates the highly conserved cysteine 743 in the catalytic domain.(B) Representative confocal images of wild-type (WT) embryos co-expressing ULP-2::GFP and DLG-1::RFP (red fluorescent protein) (Diogon et al., 2007). Images(representative of n = 86 embryos) were acquired at the end of intercalation (upper row), comma stage (middle row), and 1.5-fold stage (lower row). Arrowheadsindicate nuclei of dorsal and ventral epidermal cells. ULP-2::GFP is functional and partially rescues the ulp-2(tv380) null allele (34% embryonic lethality, n = 1,437 embryos). Scale bar, 10 um.(C) Downregulation of ULP-2::GFP expression by ulp-2(RNAi). Representative of n = 44 embryos. Scale bar, 10 um.(D) Exon-intron organization of the two identified ulp-2 isoforms, ulp-2a and ulp-2b.(E) Embryos expressing ULP-2a::GFP and ULP-2b::GFP reporters under the control of ulp-2 upstream sequences, dorsal view (representative of n = 20 and n = 14embryos, respectively). ULP-2a::GFP is both cytosolic and nuclear (yellow line marks a dorsal cell, blue line marks the nucleus, and arrow points to the cytosol), partially functional and is expressed in the ulp-2(tv380) background in order to achieve stable expression. Scale bar, 10 um.(F) 3D homology model of the catalytic domains of ULP-2a and ULP-2b generated with Phyre2 based on the crystal structure of SENP7 (PDB: 3EAY) (Lima andReverter, 2008). The catalytic cysteine (C743 in ULP-2 and C926 in SENP7) and additional conserved catalytic residues are shown in stick representation (red).Loops 2 and 3 are insertions in the catalytic domain of SENP7 (Lima and Reverter, 2008) and are absent from ULP-2. Ribbon representations were prepared withPyMOL (DeLano, 2002).

Picture from Johnson, Christina K. et al. (2021) MicroPubl Biol

Figure 1. Plasmin enhances MEC-4(d) but not UNC-8(d) currents in a MEC-6-dependent manner: Estimation plots by unpaired t-Test analysis of currents recorded in oocytes not treated and treated with plasmin (Calin-Jageman and Cumming 2019). Individual data points, means and 95% confidence intervals are shown. In each graph, on the right, the black circle and the error bars indicate the difference between the means and its 95% confidence interval. A: Currents recorded at -100 mV from oocytes expressing MEC-4(d)+MEC-2+MEC-6 not treated (light red) and treated (dark red) with 10 μg/ml plasmin, as indicated. N = 15, each. The difference between the means was 4.68 (71% increase), the lower and upper 95% confidence levels were 2.45 and 6.83 respectively (38% and 104% change, respectively). B: Same as panel A for oocytes expressing UNC-8(d)+MEC-2+MEC-6 not treated (light blue) and treated (dark blue) with plasmin. N = 7 and 5. The difference between the means was 0.94 (6% increase), the lower and upper 95% confidence levels were -1.50 and 3.38 respectively (-10% and 22% change, respectively). C: Same as in A for oocytes expressing MEC-4(d)+MEC-2 not treated (light red) and treated (dark red) with plasmin. N = 15 and 13 respectively. The difference between the means was 0.003 (0% change), the lower and upper 95% confidence levels were -0.391 and 0.398 respectively (-41% and 41% change; such large percentage changes are due to the relatively large variability of small currents). D: Same as panel A for oocytes expressing UNC-8(d)+MEC-2 not treated (light blue) and treated (dark blue) with plasmin. N = 6 and 5. The difference between the means was -0.87 (6% decrease), the lower and upper 95% confidence levels were -3.92 and 2.17 respectively (-27% and 15% change, respectively). E: Alignment of the finger domain of MEC-4 and UNC-8 containing the predicted plasmin sites (yellow background). F: Schematic representation of a DEG/ENaC channel subunit based on its crystal structure (Jasti, Furukawa et al. 2007). Alpha helixes are shown as cylinders and beta sheets are represented as flat arrows. The finger domain (purple) contains the plasmin recognition site (yellow box). The shaded area around transmembrane domains 1 and 2 (TM1 and TM2) represents plasma membrane.