Smith KR et al. (2011) Cytoskeleton (Hoboken) "A role for central spindle proteins in cilia structure and function."

Wang PI, Basten SG, Marcotte EM, Giles RH, Wallingford JB, Kieserman EK, Smith KR

[Cytoskeleton (Hoboken), 2011]

Cytokinesis and ciliogenesis are fundamental cellular processes that require strict coordination of microtubule organization and directed membrane trafficking. These processes have been intensely studied, but there has been little indication that regulatory machinery might be extensively shared between them. Here, we show that several central spindle/midbody proteins (PRC1, MKLP-1, INCENP, centriolin) also localize in specific patterns at the basal body complex in vertebrate ciliated epithelial cells. Moreover, bioinformatic comparisons of midbody and cilia proteomes reveal a highly significant degree of overlap. Finally, we used temperature-sensitive alleles of PRC1/spd-1 and MKLP-1/zen-4 in C. elegans to assess ciliary functions while bypassing these proteins' early role in cell division. These mutants displayed defects in both cilia function and cilia morphology. Together, these data suggest the conserved reuse of a surprisingly large number of proteins in the cytokinetic apparatus and in cilia.

Liu Y et al. (2018) Int J Mol Med "Kushui Rose (R.SetatexR.Rugosa) decoction exerts antitumor effects in C. elegans by downregulating Ras/MAPK pathway and resisting oxidative stress."

Liu Y, Chen P, Li H, Wang X, Fei D, Wu Z, Li Y, Zhang Z, Zhi D

[Int J Mol Med, 2018]

Kushui rose (R.SetatexR.Rugosa) (KR) is a traditional Chinese medicine proven to be a potent antioxidant, and used for thousands of years. Approximately 30% of all human cancers relevant to mutational activated Ras, and over-activated Ras are accompanied by increased accumulation of reactive oxygen species (ROS). Thus, one way of developing anticancer drugs is to reduce ROS accumulation. Therefore, KR was predicted to have potential to combat over-activated Ras-related cancer. C.elegans with let60(gf)/ras mutant, which exhibited tumor-like symptoms of the multivulva phenotype, was employed to determine the effect of KR on Ras/MAPK pathway. Other strains of worms and H2DCF-DA dye were also applied to study the antioxidant stress capacity of KR. This study was aimed to determine whether KR has a potential effect on combat over-activated Ras-related cancer through resistance to oxidative stress. Our results showed that Kushui rose decoction (KRD) has potent antioxidant activity invitro, and can inhibit over-activated Ras invivo. Further, KRD significantly suppressed over-activated Ras/MAPK pathway by regulating oxidative stress-related proteins, such as forkhead transcription factor (DAF-16), glutathione S-transferase-4 (GST-4), superoxide dismutases(SODs) and heat shock protein-16.2(HSP-16.2). However, essential oil and hydrosol of KR had no effect on over-activated Ras. Thus these results reminded us that people usually soak rose in hot water to prepare 'rose tea' as an effective way for health care. Thus, KRD was demonstrated to be a potential drug candidate for combating over-activated Ras-related cancer as an antioxidant.

Fu, Donald et al. (2011) International Worm Meeting "In situ study of oxidative stress using a new optogenetic tool, KillerRed."

Fu, Donald, Kotera, Ippei, Suzuki, Hiroshi, Su, Po-An

[International Worm Meeting, 2011]

Parkinson's Disease (PD), characterized by the progressive degeneration of dopaminergic (DA) neurons, leads to locomotive deficits. Genetic studies suggests a role for oxidative stress in impairing activity and viability of DA neurons. Conventional methods induced stress in C. elegans by administering mitochondrial respiratory chain inhibitors (such as rotenone and paraquat) to the growth medium. However, these drugs diffuse and affect all cells in animals, and the effects have mostly been scored by the animals' death. It is difficult to assess how drugs affect only DA neurons and locomotive deficits. To overcome these limitations, we adopt a new optogenetic tool, KillerRed: a red fluorescent protein engineered to generate oxygen radicals on photoactivation. KR can be genetically targeted to cells by cell-specific promoters, and to specific subcellular compartments by site-localization motifs. We can also control irradiation time and intensity to manipulate timing and duration of stress. Studies have shown its potency in inducing cell death in mammalian cultured cells and Zebrafish. To test this tool in C. elegans, we investigated its effects on the mechanosensory system by expressing KR solely in touch neurons using mec-4p and scoring morphology and behavior (forward escape mediated by PLM neurons). We established a method to confirm activation: after photoactivation, KR fluorescence diminished to <1% of its initial levels, with a decay half-life of ~5.43s. Irradiation of PLM neurons for 10mins lead to profound changes in cell shape or their disappearance within 2h, without affecting neighboring KR(-) cells. Behavioral analysis revealed 73% reduction in touch sensitivity. We are now applying this tool to study oxidative stress in DA neurons; we targeted KR to the mitochondria using dat-1p and cytochrome-c oxidase motif. To quantitatively examine locomotion dependence on DA neurons, we employ a computer behavior analysis system: Our new worm tracker allows comparison of stressed worms to wild-type, to DA-deficient cat-2 mutants, and directly address DA-activity suppression via optogenetic tools (dat-1p::NpHR). We are also expressing KR in other subcellular compartments and crossing them with mutants of PD genes (such as pdr-1, djr-1.1/2, pink-1) to examine how they protect against stress in DA neurons. Thus, we propose that KR is a useful tool to study oxidative stress and for in vivo ablation of neurons in C. elegans.

Rosenberg R (1978) Worm Breeder's Gazette

Rosenberg R

[Worm Breeder's Gazette, 1978]

All eyes are on the newest fashion trend, the Dumpy Look . Pace setting designer I.M. Worm s androgynous wardrobe is all the rage in Paris. Bianca Jagger quips, Tres, tres - Women s Wear Daily writes, Elegans personified - Patti Smith thinks, The punks won t buy it and Craig Russell says, It fits right in with my act . A product of Mutant Isolation, Inc.

Potet F et al. (2009) J Mol Cell Cardiol "Genetic screening in C. elegans identifies rho-GTPase activating protein 6 as novel HERG regulator."

Boutaud O, Petersen CI, Stepanovic SZ, Potet F, Kupershmidt S, Shuai W, Balser JR

[J Mol Cell Cardiol, 2009]

The human ether-a-go-go related gene (HERG) constitutes the pore forming subunit of I(Kr), a K(+) current involved in repolarization of the cardiac action potential. While mutations in HERG predispose patients to cardiac arrhythmias (Long QT syndrome; LQTS), altered function of HERG regulators are undoubtedly LQTS risk factors. We have combined RNA interference with behavioral screening in Caenorhabditis elegans to detect genes that influence function of the HERG homolog, UNC-103. One such gene encodes the worm ortholog of the rho-GTPase activating protein 6 (ARHGAP6). In addition to its GAP function, ARHGAP6 induces cytoskeletal rearrangements and activates phospholipase C (PLC). Here we show that I(Kr) recorded in cells co-expressing HERG and ARHGAP6 was decreased by 43% compared to HERG alone. Biochemical measurements of cell-surface associated HERG revealed that ARHGAP6 reduced membrane expression of HERG by 35%, which correlates well with the reduction in current. In an atrial myocyte cell line, suppression of endogenous ARHGAP6 by virally transduced shRNA led to a 53% enhancement of I(Kr). ARHGAP6 effects were maintained when we introduced a dominant negative rho-GTPase, or ARHGAP6 devoid of rhoGAP function, indicating ARHGAP6 regulation of HERG is independent of rho activation. However, ARHGAP6 lost effectiveness when PLC was inhibited. We further determined that ARHGAP6 effects are mediated by a consensus SH3 binding domain within the C-terminus of HERG, although stable ARHGAP6-HERG complexes were not observed. These data link a rhoGAP-activated PLC pathway to HERG membrane expression and implicate this family of proteins as candidate genes in disorders involving HERG.

Kravtsov, V. et al. (2013) International Worm Meeting "The effects of aging on dendritic plasticity and PVD-FLP branch coexistence."

Podbilewicz, B., Oren-Suissa, M., Kravtsov, V.

[International Worm Meeting, 2013]

Self-avoidance, tiling and coexistence are the main mechanisms that enable the best dendritic coverage. C. elegans undergoes aging-associated changes that ultimately lead to decreased functionality of the organism, including its neurological functions. Recent research has shown that the nervous system of C. elegans undergoes changes and alterations during aging including dendritic morphology (Tank et al., 2011). We study dendritic plasticity, aging and spatial dendritic organization of two highly arborized mechanoreceptors in C. elegans, PVD and FLP (Oren-Suissa et al., 2010). PVD dendrites of L4s and young adults show regenerative ability following dendrotomy (laser induced severing of dendrites). Our working hypothesis is that in older ages this ability to regenerate is compromised. Previous studies and our preliminary results indicate that PVD and FLP do not overlap in larval stages (Smith et al., 2010). In addition, dendrites within each bilateral PVD do not overlap through a self-avoidance mechanism (Smith et al., 2012). We found that (1) the coverage fields of the PVD and FLP overlap in adult worms, which indicates coexistence and not tiling. This overlap increases as the worm ages. (2) PVDs show aberrant arborization at the age of 9 days of adulthood. (3) Dramatic increase in self-avoidance defects as animals age. In humans many neurodegenerative diseases as well as generalized cognitive decline are associated with age, aberrant arborization or both (e.g. autism and Alzheimer's disease). However our understanding of how these disorders are triggered and aggravated is scarce. Our research provides an insight into the aging and regeneration process of individual neurons. Oren-Suissa, M., et al. (2010). Science 328, 1285-1288. Smith, C.J. et al. (2010). Developmental Biology 345, 18-33. Smith, C.J., et al. (2012). Nature Neuroscience 15, 731-737. Tank, E.M.H. et al. (2011). Journal of Neuroscience 31, 9279-9288.

Stroustrup N et al. (2016) Nature "The temporal scaling of Caenorhabditis elegans ageing."

Apfeld J, Gowda V, Nash ZM, Stroustrup N, Fontana W, Gomez A, Anthony WE, Lopez-Moyado IF

[Nature, 2016]

The process of ageing makes death increasingly likely, involving a random aspect that produces a wide distribution of lifespan even in homogeneous populations. The study of this stochastic behaviour may link molecular mechanisms to the ageing process that determines lifespan. Here, by collecting high-precision mortality statistics from large populations, we observe that interventions as diverse as changes in diet, temperature, exposure to oxidative stress, and disruption of genes including the heat shock factor hsf-1, the hypoxia-inducible factor hif-1, and the insulin/IGF-1 pathway components daf-2, age-1, and daf-16 all alter lifespan distributions by an apparent stretching or shrinking of time. To produce such temporal scaling, each intervention must alter to the same extent throughout adult life all physiological determinants of the risk of death. Organismic ageing in Caenorhabditis elegans therefore appears to involve aspects of physiology that respond in concert to a diverse set of interventions. In this way, temporal scaling identifies a novel state variable, r(t), that governs the risk of death and whose average decay dynamics involves a single effective rate constant of ageing, kr. Interventions that produce temporal scaling influence lifespan exclusively by altering kr. Such interventions, when applied transiently even in early adulthood, temporarily alter kr with an attendant transient increase or decrease in the rate of change in r and a permanent effect on remaining lifespan. The existence of an organismal ageing dynamics that is invariant across genetic and environmental contexts provides the basis for a new, quantitative framework for evaluating the manner and extent to which specific molecular processes contribute to the aspect of ageing that determines lifespan.

Cassada RC et al. (1980) Worm Breeder's Gazette "initial characterization of ts embryonic defective (emb) mutants (Goettingen set)."

Culotti MR, Cassada RC, Von Ehrenstein G, Isnenghi E

[Worm Breeder's Gazette, 1980]

[See Figure 1] Already published allelism: Wood et al., 1980: b117=b189; b246 = let- 2.Miwa et al., 1980: hc57 = hc62; hc61 = hc67. Our global complementation results: g1 = g4; g16 = g65 = hc61 = hc67; g36 = hc65; g23 = g34 = hc70 = b117 = b189; g37 = b246 = let-2; b84 = hc66; g14 = g43; g57 = b1O. From frequency of multiple alleles we estimate 200-400 genes essential for embryogenesis. Mapping is in progress. We are also doing tsp's, R + H Tests, and cellular defects ( Isnenghi, Cassada, Radnia, Schierenberg, K. Smith, v. Ehrenstein).

Petersen CI et al. (2004) Proc Natl Acad Sci U S A "In vivo identification of genes that modify ether-a-go-go-related gene activity in Caenorhabditis elegans may also affect human cardiac arrhythmia."

Stepanovic SZ, Reiner DJ, Hayashi K, Balser JR, George AL, Roden DM, McFarland TR, Petersen CI, Thomas JH, Yang P

[Proc Natl Acad Sci U S A, 2004]

Human ether-a-go-go-related gene (HERG) encodes the pore-forming subunit of I-Kr, a cardiac K+ channel. Although many commonly used drugs block I-Kr, in certain individuals, this action evokes a paradoxical life-threatening cardiac rhythm disturbance, known as the acquired long QT syndrome (aLQTS). Although aLQTS has become the leading cause of drug withdrawal by the U.S. Food and Drug Administration, DNA sequencing in aLQTS patients has revealed HERG mutations only in rare cases, suggesting that unknown HERG modulators are often responsible. By using the worm Caenorhabditis elegans, we have developed in vivo behavioral assays that identify candidate modulators of unc-103, the worm HERG orthologue. By using RNA-interference methods, we have shown that worm homologues of two HERG-interacting proteins, Hyperkinetic and K channel regulator 1 (KCR1), modify unc-103 function. Examination of the human KCR1 sequence in patients with drug-induced cardiac repolarization defects revealed a sequence variation (the substitution of isoleucine 447 by valine, I447V) that occurs at a reduced frequency (11.1%) relative to a matched control population (7.0%), suggesting that I447V may be an allele for reduced aLQTS susceptibility. This clinical result is supported by in vitro studies of H ERG dofetilide sensitivity by using coexpression of HERG with wild-type and 1447V KCR1 cDNAs. Our studies demonstrate the feasibility of using C. elegans

Burke DJ et al. (1979) Worm Breeder's Gazette "studies on the X-chromosome of Panagrellus redivivus."

Burke DJ, Samoiloff MR, Schulz S

[Worm Breeder's Gazette, 1979]

Mutants on the X-chromosome of the dioecious Panagrellus redivivus have been isolated and mapped. Four uncs and a long have been maintained in both sexes. Paralysed, twitchers and dumpies have been obtained, but males fail to mate. Three of the uncs have reduced mobility or coordination, while the fourth unc contracts when tapped on the head, but will not reverse. The long mutant is approximately 30% longer than wild type, with no decrease in body width, Recently a new phenotype, skinny, more than 100% longer and 25% thinner has been isolated by Yvonne Jordan. The frequency of mutation using standard EMS mutagenesis of L4s is 4. 4 X 10+E-4 mutations per visible locus. The number of essential genes on the P. redivivus X-chromosome is calculated at 320 on the basis of the frequency of lethal mutations corrected for double events. The gamma-irradiation induced mutation rate is 9 X 10+E-7 mutations per locus per rad, using a dose-rate of 4.5 Kr/min. Genetically marked L2s were exposed to doses of gamma radiation varying from 5 to 150 Kr. Using target theory applied to males it was calculated that 180, 130 and 1800 X-linked genes in the total P. redivivus genome are required to complete the second, third and final moult, respectively. The kinetics of the failure of females to develop after gamma-irradiation was more indicitive of chromosome breaks rather than point mutation.