Hills, A.J. et al. (2017) International Worm Meeting "Markov chain Monte Carlo simulation of the dauer larvae formation decision-making and signalling in populations of Caenorhabditis elegans."

Hills, A.J., Harvey, S.C., Viney, M.E.

[International Worm Meeting, 2017]

Phenotypic plasticity allows species to respond to environmental changes. In the wild, populations of the nematode Caenorhabditis elegans develop and grow in nutrient-rich, ephemeral habitats. Movement between these ephemeral patches, and long term genotype survival, depends on the development of dauer larvae. Within these natural populations, survival is therefore dependent upon a critical development decision, as worms must commit to either a reproductive fate to increase local numbers, or a migratory fate to find new resources to exploit. Failure to disperse at the correct time will result in loss of the local population with the resources in the ephemeral habitat. Under laboratory conditions, the decision between dauer and non-dauer larval development is driven by ascaroside signalling - which acts as a proxy for population size - by food availability, and by temperature. However, phenotypic differences between genotypes in reaction to these factors is substantial. For example, ascaroside production profiles vary between genotypes as do the responses to specific ascarosides and to mixtures of ascarosides. There is also evidence that suggests that ascaroside signalling by worms may be manipulative. Here we present the results of Markov Chain Monte Carlo (MCMC) simulations of modelled C. elegans genotypes optimising the developmental switch under different environmental pressures. The simulation results are compared with a number of wild-type strains. The evolution of ascaroside signalling is examined with the additional effects of exposure to signal distortion and noise as may be present in heterogeneous wild habitats. The model is presented in the form of a generalizable method for studying developmental decisions and other phenotypically plastic traits under a variety of environmental conditions.

Hills AJ et al. (2017) Dev Genes Evol "Mutation independently affects reproductive traits and dauer larvae development in mutation accumulation lines of Caenorhabditis elegans."

Hills AJ, Harvey SC, Green JWM

[Dev Genes Evol, 2017]

Developmental decisions are important in organismal fitness. For the nematode Caenorhabditis elegans, which is naturally found in the ephemeral food patches formed by rotting plant material, correctly committing to dauer or non-dauer larval development is key to genotype survival. To investigate the link between reproductive traits, which will determine how populations grow, and dauer larvae formation, we have analysed these traits in mutation accumulation lines of C. elegans. We find that reproductive traits of individual worms-the total number of progeny and the timing of progeny production-are highly correlated with the population size observed in growing populations. In contrast, we find no relationship between reproduction traits and the number of dauer larvae observed in growing populations. We also do not observe a mutational bias in dauer larvae formation. These results indicate that the control of dauer larvae formation is distinct from the control of reproduction and that differences in dauer larvae formation can evolve rapidly.

Eddy SR (1994) Worm Breeder's Gazette "Three Families of Reverse Transcriptase Elements in C. elegans"

Eddy SR

[Worm Breeder's Gazette, 1994]

Three families of reverse transcriptase elements in C. elegans Sean Eddy, MRC-LMB, Hills Road, Cambridge CB2 2QH, UK

Kuwabara PE (1994) Worm Breeder's Gazette "Evidence For Interactions Between the Sex Determination and Dosage Compensation Pathways in the Germline"

Kuwabara PE

[Worm Breeder's Gazette, 1994]

Evidence for Interactions Between the Sex Determillation and Dosage Compensation Pathways in the Germline Patricia E. Kuwabara MRC-LMB Hills Road Cambridge CB2 2QH England

Chuang P-T et al. (1994) Worm Breeder's Gazette "DPY-27: A Protein Required For Dosage Compensation is Associated With the X Chromosome in XX Animals"

Chuang P-T, Meyer BJ, Albertson DG

[Worm Breeder's Gazette, 1994]

Dpy-27: A Protein Required for Dosage Compensation Is Associated with the X chromosome in XX Animals Pao-Tien Chuangl, Donna Albertson2 and Barbara Meyerl, Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720~ and MRC Laboratory of Molecular biology, Hills Road, Cambridge, CB2 2QH UK2

Mehra A et al. (1994) Worm Breeder's Gazette "Direct Interaction Between FEM-3 and a Carboxy-Terminal Fragment of TRA-2A"

Spence AM, Heck L, Kuwabara PE, Mehra A

[Worm Breeder's Gazette, 1994]

Direct Interaction between FEM-3 and a Carboxy-Terminal Fragment Or TRA-2A Arun Mehra, Linda Heck, Patricia Kuwabara*, and Andrew Spence Dept. of Medical Genetics, University of Toronto, 1 King's College Circle, Toronto, Canada, and *MRC Laboratory of Molecular Biology, Hills Rd., Cambridge, UK

Calhoun, Adam et al. (2011) International Worm Meeting "Spatial memory in C. Elegans."

Chalasani, Sreekanth, Sharpee, Tatyana, Calhoun, Adam

[International Worm Meeting, 2011]

Worms are known to increase the frequency of turning and reversal events in response to removal of a food stimulus. This keeps the animal in a small area near the last observation of food. The increase in turning frequency is known to be regulated by dopamine and glutamate (Hills et al 2004). We have found that the search strategy is modified by the spatial pattern of food that is experienced. Worms adapt quickly to new food environments, learning spatial patterns on short timescales. The dopamine deficient cat-2 mutant is unable to learn different spatial patterns, suggesting that dopamine is required for spatial memory. References Hills T, Brockie PJ, Maricq AV (2004). Dopamine and glutamate control area-restricted search behavior in Caenorhabditis elegans. J Neurosci 24(5): 1217-1225.

Hodgkin JA et al. (1997) Worm Breeder's Gazette "CGC Genetic Map and Nomenclature Subcontract"

Hodgkin JA, Durbin RM, Martinelli SD

[Worm Breeder's Gazette, 1997]

1997 Genetic Map The deadline for new genetic map data to be incorporated into the 1997 Genetic Map of Caenorhabditis elegans (Printed Version) is 30 April 1997. Data can be sent: (preferably) by e-mail to: cgc@mrc-lmb.cam.ac.uk. Forms for data submission are available by e-mail or fax, on request to this address. (or alternatively) by fax or mail, to: Jonathan Hodgkin, MRC-LMB, Hills Road, Cambridge CB2 2QH, England [fax (+44) 1223 412142]

Zuckerman BM (1974) "The effects of procaine on aging and development of a nematode."

Zuckerman BM

[1974]

The free-living nematode, Caenorhaditis briggsae, is being used in our laboratory to study the complex events associated with biological aging. Our approach to this problem involved first the defining of parameters characterizing senescence in this animal, and then evaluating the effects on these aging signs of a drug reported to have a modifying effect on some aspects of the aging processes. Reference in this report to this preparation, Gerovital H3 (2% procaine hydrochloride, 0.16% benzoic acid, 0.14% potassium metabisulfite, buffered to pH 3.3 from Rom-Amer Pharmaceuticals, Ltd., Beverly Hills, California) is by its active ingredient, "Procaine".

Chitwood DJ (1999) Crit Rev Biochem Mol Biol "Biochemistry and function of nematode steroids."

Chitwood DJ

[Crit Rev Biochem Mol Biol, 1999]

Although largely hidden from public view, nematodes are among the most numerous and ecologically diverse multicellular organisms inhabiting the planet. Although most species are microbivorous, numerous species are economically or medically important parasites of plants and animals. As Cobb wrote 80 years ago, "If all the matter in the universe except the nematodes were swept away, our world would still be dimly recognizable, and if, as disembodied spirits, we could then investigate it, we should find its mountains, hills, vales, rivers, lakes and oceans represented by a film of nematodes. The locations of towns would be decipherable, since for every massing of human beings there would be a corresponding massing of certain nematodes. The location of the various plants and animals would still be decipherable, and has we sufficient knowledge, in many cases their species could be determined by an examination of their erstwhile nematode parasites".