Simske JS et al. (1994) Worm Breeder's Gazette "Specification of Vulval Cell Fates By Sequential Signalling Pathways."

Simske JS, Kim SK

[Worm Breeder's Gazette, 1994]

Specification of vulval cell fates by sequential signaling pathways Jeffrey S. Simske and Stuart K. Kim, Dept. of Developmental Biology, Stanford University Medical Center, Stanford CA 94305

Thomas JH et al. (1994) Worm Breeder's Gazette "lin-36, a Class B Synthetic Multivulva Gene, Encodes a Novel Protein"

Thomas JH, Horvitz HR

[Worm Breeder's Gazette, 1994]

lin-36, a Class B Synthetic Multivulva Gene, Encodes a Novel Protein Jeffrey H. Thomas and H. Robert Horvitz, HHMI, Dept. Biology, MIT, Cambridge, MA 02139, USA

Tonks NK (2009) Cell "Pseudophosphatases: grab and hold on."

Tonks NK

[Cell, 2009]

Catalytically inactive pseudophosphatases are able to signal in the absence of enzymatic activity. Analyzing the oocyte-to-zygote transition in the worm, Cheng et al. (2009) and Parry et al. (2009) now show how two pseudophosphatases, EGG-4 and EGG-5, can regulate signaling by the DYRK family kinase MBK-2.

Tcherpakov M et al. (2008) Mol Biol Cell "JAMP optimizes ERAD to protect cells from unfolded proteins."

Tempst P, Broday L, Erdjument-Bromage H, Ronai Z, Tcherpakov M, Qiu XB, Kadoya T, Khurana A, Delaunay A, Demartino GN

[Mol Biol Cell, 2008]

Monitoring Editor: Jeffrey L. Brodsky Clearance of misfolded proteins from the ER is central for maintenance of cellular homeostasis. This process requires coordinated recognition, ER-cytosol translocation, and finally ubiquitination-dependent proteasomal degradation. Here, we identify an ER resident 7-transmembrane protein (JAMP) that links ER chaperones, channel proteins, ubiquitin ligases, and 26S proteasome subunits, thereby optimizing degradation of misfolded proteins. Elevated JAMP expression promotes localization of proteasomes at the ER, with a concomitant effect on degradation of specific ER-resident misfolded proteins, whereas inhibiting JAMP promotes the opposite response. Correspondingly, a jamp-1 deleted C. elegans strain exhibits hypersensitivity to ER stress and increased UPR. Using biochemical and genetic approaches, we identify JAMP as important component for coordinated clearance of misfolded proteins from the ER.

George Cachianes et al. (2003) International Worm Meeting "Worms? In High School?"

Julie Reis, Cynthia Portillo, Amanda Kahn-Kirby, Cindy Wan, George Cachianes, Ivannia DeAlba, Tanya Gomerman, Brad Still, Jeffrey Cheng, Sandy Wong

[International Worm Meeting, 2003]

We are Abraham Lincoln High School students using C. elegans in an after-school research class with a sufficiently equipped lab. C. elegans is a good model system for us because there are no ethical issues surrounding its use, it is safe, has a short life span, is easy to grow in a small space, doesn't require special facilities, and is cheap! C. elegans was new to us, so we began the year by learning the basics: mixing media pouring plates, culturing bacteria, seeding plates, identifying males and hermaphrodites, staging worms, comparing N2 and mutants, and setting up crosses. In two months, we became skilled at pipetting, microscopy, sterile technique, chunking, and picking worms. After we had acquired basic skills, we learned how to search the literature. To understand abstracts, we learned new vocabulary. In the process of researching previous work we developed our own questions, and each of us wrote a research proposal. We then merged our ideas and formed two research teams. One team grew C. elegans on Bacillus subtilis, and the other tested the ability of hermaphrodites and males to negotiate a maze. The B. subtilis team first asked whether worms would survive on the thick, malodorous lawn. We then asked if there would be morphological, life cycle, or chemotaxis differences between worms fed B. subtilis and worms fed E. coli. Our data indicated that worms grew on B. subtilis and that, after many generations, they progressed normally through development and continued to show normal morphology. We are continuing to look for sensory disparity using a chemotaxis assay with benzaldehyde or diacetyl as the attractant. The maze team designed a maze using copper to repel worms. We are collecting data comparing the ability of E. coli-fed hermaphrodites versus males to negotiate our maze. We would like to expand the study to include assays with B. subtilis-fed worms. Worm research has gone well at Abraham Lincoln High School. We have asked our own questions, and designed and conducted our own experiments to find answers. We highly recommend that other high schools work with C. elegans. To be successful, the schools need equipment to culture worms, funding for disposable materials, dedicated teachers, and motivated students willing to spend time to do scientific research. The assistance of a scientist with knowledge about C. elegans is also helpful.

Zhu L et al. (2008) Mol Biol Cell "The torsin-family AAA+ protein OOC-5 contains a critical disulfide adjacent to Sensor-II that couples redox state to nucleotide binding."

Rose LS, Thomas PJ, Hayashi AP, Zhu L, Wrabl JO

[Mol Biol Cell, 2008]

Monitoring Editor: Jeffrey L. Brodsky A subgroup of the AAA+ proteins that reside in the endoplasmic reticulum and the nuclear envelope including human torsinA, a protein mutated in hereditary dystonia, is called the torsin family of AAA+ proteins. A multiple-sequence-alignment of this family with Hsp100 proteins of known structure reveals a conserved cysteine in the C-terminus of torsin proteins within the Sensor-II motif. A structural model predicts this cysteine to be a part of an intramolecular disulfide bond, suggesting that it may function as a redox sensor to regulate ATPase activity. In vitro experiments with OOC-5, a torsinA homolog from C. elegans, demonstrate that redox changes that reduce this disulfide bond affect the binding of ATP and ADP and cause an attendant local conformational change detected by limited proteolysis. Transgenic worms expressing an ooc-5 gene with cysteine to serine mutations that disrupt the disulfide bond have a very low embryo hatch rate compared with wild type controls, indicating these two cysteines are essential for OOC-5 function. We propose that the Sensor-II in torsin family proteins is a redox-regulated sensor (RRS). This regulatory mechanism may be central to the function of OOC-5 and human torsinA.

G Kao et al. (1999) International C. elegans Meeting "Characterization of Laminin beta and gamma Genes."

G Kao, C Huang, WG Wadsworth

[International C. elegans Meeting, 1999]

We have characterized laminin b (lam-1) and laminin g (lam-2) genes. The sequencing project has uncovered genes for one isoform each of the two subunits and two isoforms of laminin a , epi-1 and lam-3. (See abstract by Cheng et al.). This indicates that two types of trimers likely are form in basement membranes : a A bg and a B bg . A hypomorphic mutation (rh219) exists in lam-1, whose phenotypes we have described in previous meetings (IWM 1997). Both lam-1(RNAi) and lam-2(RNAi) animals arrest development during morphogenesis. Significantly, this phenotype is identical to the arrest seen in double knockout of epi-1 and lam-3, and is more severe than either knockout alone. We examined the expression patterns of lam-1 and lam-2 using promoter:GFP fusions. Both genes are expressed in body wall muscles, pharynx, vulval muscles, the rectal muscle group and the distal tip cells. The expression patterns of b and g subunit genes overlap with and are more widespread than either epi-1 or lam-3 alone. Taken together these results suggest that lam-1 and lam-2 are found in all basement membranes and indicate that trimers a A bg and a B bg are formed.

Cho, Jihye et al. (2021) International Worm Meeting "Identify the function of mechanosensitive channel PEZO-1 in C. elegans males"

Cho, Jihye, Kim, Kyuhyung

[International Worm Meeting, 2021]

The conversion of mechanical force to biological signals is crucial for the survival of animals. Mechanosensitive ion channels play a direct role in sensing physical stimuli and are evolutionarily conserved from bacteria to mammals. In mammals, PIEZO channels have been identified as ion channels that directly detect mechanical stimuli (Coste et al., 2010, Gnanasambandam et al., 2015, Syeda et al., 2015). C. elegans genome has a single PIEZO gene, pezo-1, which encodes 14 isoforms (Bai X et al., 2020). However, the function of PEZO-1 in C. elegans has not been fully understood yet. To investigate its function, we first grouped 14 isoforms into short or long isoforms depending on the mRNA length and observed their expression patterns. We found that the promoter region of short isoforms is expressed in several tail neurons, including the 6th ray neurons of C. elegans males. Nine pairs of male ray neurons appear to have functional specialization and have been implicated to be involved in mating behavior (Zhang H, Yue X, Cheng H, et al., 2018). Interestingly, sensory endings of ray 6 neurons, but not other ray neurons, are not exposed to the external environment (Sulston and Horvitz, 1977), suggesting a distinct role in mechanotransduction during C. elegans mating. We are currently examining the contribution of PEZO-1 to mating behavior in males.

Hung M-S et al. (1994) Worm Breeder's Gazette "vab-8 Rescued: Another Gene Involved In Controlling Cell Polarity?"

Hung M-S, Way JC

[Worm Breeder's Gazette, 1994]

Vab-8 rescued: Another gene involved in controlling cell polarity? Ming-Shiu Hung and Jeffrey C. Way. Nelson Biol. Lab., Rutgers University, Piscataway, NJ08855. Asymmetric cell division is a common feature of developing organisms. Defects in axon outgrowth and migration might share the same kind of controlling mechanism as asymmetric cell division, since they all fail to sense the right orientation. By screening uncoordinated mutants with defects in axon guidance or cell migration, vab-8 (vab denotes variable abnormal) was found to have defects in asymmetric cell division in addition to its known defect in migration of the CAN cell and the HSN cell (Manser and Wood, 1990) . The phenotype of vab-8 shows withered tail and secondary vulval protrusions. The double mutant of vab-8;unc-73 is lethal and vab-8/+;unc 73/+ animals are sometimes uncoordinated (-10% penetrance). The mutant phenotype of unc-73 also shows defects in axon outgrowth and migration and has mild defects in asymmetric cell divisions. In addition, unc-73 shares -200 amino acid region with CDC24, which controls the orientation of bud position and the direction of "shmoo" process extension in Sacchromyces cerevisiae. Therefore, vab-8 may be part of a directional sensation mechanism within C. elegans. I am trying to clone vab-8. A single cosmid, C35G11, is able to rescue vab-fl but a derivative lacking 7Kb does not rescue. Other smaller constructs are being made. Manser, J. and W. B. Wood. 1990. Mutations affecting embryonic cell migrations in Caenorhabditis elegans. Develop. Genet., 11:49-64.

Riga, Amalia et al. (2019) International Worm Meeting "The role of basolateral polarity regulators in epithelial tissue homeostasis."

Boxem, Mike, Pires, Helena, Riga, Amalia

[International Worm Meeting, 2019]

Polarization of epithelial cells into apical and basolateral domains is essential for the functioning of epithelia as selectively permeable barriers. The basolateral Scribble group proteins (Scrib, Lgl, Dlg) were originally identified as tumor suppressors in D. melanogaster and were later shown to play key roles in the establishment and maintenance of polarity in a broad range of cell types. In addition to promoting basolateral identity, Scribble group proteins regulate diverse processes including tissue growth, differentiation and directed cell migration, and therefore are major regulators of tissue development and homeostasis. In C. elegans, loss of LET-413/Scrib and DLG-1/Dlg results in defects in epithelial polarization and junction formation during embryonic development, resulting in embryonic lethality. However, their importance in larval epithelia is less well understood. To study the role of LET-413 in larval epithelia, we generated an allele that allows inducible protein degradation using the auxin-inducible system recently developed for C. elegans (1). We find that ubiquitous degradation of LET-413 in larval tissues results in a developmental arrest. Tissue-specific degradation of LET-413 in the larval intestine does not cause defects in development. In contrast, degradation of LET-413 in the seam cells and hypodermis mimics the developmental arrest seen upon ubiquitous LET-413 degradation. Live-cell imaging of seam cells shows a severe effect on outgrowth and reattachment following the L1 asymmetric division. In addition, we observed that loss of LET-413 results in punctate and discontinuous localization pattern of DLG-1, similar to previous observations in C. elegans embryos. We are currently following the effects of LET-413 inactivation on cell recognition and migration pathways to understand the outgrowth defects of the seam cells. (1) Zhang L, Ward JD, Cheng Z, Dernburg AF. Development. 2015 Dec 15;142(24):4374-84.