Piggott, Beverly J. et al. (2009) International Worm Meeting "Dissecting the neural basis for locomotion in freely-behaving worms."

Liu, Jie, Piggott, Beverly J., Feng, Zhaoyang, Xu, X.Z. Shawn

[International Worm Meeting, 2009]

Locomotion represents one of the most basic motor programs in the C. elegans behavioral repertoire. The command interneurons are believed to be the primary drivers of forward and backward locomotion. To better understand the role of these neurons in both sensory and spontaneous behavior, we have developed an automated calcium imaging system that permits simultaneous imaging of neural activity and behavior in freely-moving worms. We have named it the CARIBN system (CAlcium Ratiometric Imaging of Behaving Nematodes). Previous studies have been primarily conducted on restrained or semi-restrained worms that do not exhibit natural behavior. Our system provides a means to temporally examine how neural activity correlates to behavior under standard laboratory conditions where worms freely move on the surface of an NGM plate in an open environment. By using standard laboratory conditions, we can compare our work to the majority of behavioral studies performed by other groups over the past 40 years. We currently focus on the neuron AVA, as it has been implicated as a primary driver of backward locomotion in both spontaneous and sensory induced behaviors. Consistent with other reports, we found that AVA is activated in response to nose touch, osmotic shock, and in spontaneous long reversals. Surprisingly, we do not see a significant AVA activity in spontaneous short reversals. The CARIBN system provides a powerful tool to dissect how genes and neural circuits generate behavior in C. elegans.

Piggott, Beverly J. et al. (2011) International Worm Meeting "Mammalian rhodopsin can functionally substitute for C. elegans photoreceptor to restore light sensitivity in worms."

Piggott, Beverly J., Liu, Jie, Xu, X.Z. Shawn, Gao, Jingwei

[International Worm Meeting, 2011]

We have recently discovered that worms sense light and engage in phototaxis behavior that is essential to their survival. Our work has led to the identification of photoreceptor neurons and molecules in the C. elegans phototransduction pathway. Through electrophysiological interrogation, we discovered that LITE-1 acts in ASJ to transduce light signals through a G protein-mediated process which requires membrane-associated guanylate cyclases. This pathway shares striking similarities to those found in some vertebrate photoreceptor cells. Interestingly, lite-1 belongs to the invertebrate taste receptor family. Discovering that a gustatory receptor could permit light sensation in worms, we wondered if expression of other known light sensing molecules, such as opsins, could function similarly in worms. In other words, could structurally distinct, mammalian opsins, hijack the C. elegans phototransduction machinery to restore photosensory behavior in lite-1 mutants? To this end we made transgenic worms expressing bovine rhodopsin and discovered that it can restore light sensitivity in lite-1 mutants. These findings demonstrate that divergent photoreceptor molecules can share functional homology.

Wani, Khursheed A. et al. (2015) International Worm Meeting "Elucidating the role of interneuron RIM in the regulation of C. elegans locomotion."

Wani, Khursheed A., Li, Zhaoyu, Xu, Shawn, Piggott, Beverly J.

[International Worm Meeting, 2015]

Locomotion is a predominant motor program in C. elegans. During locomotion, C. elegans usually moves forward that is periodically interrupted by brief reversals. The neurons that control forward and backward locomotion are well characterized. The command interneuron, AVB, is known to drive forward locomotion, and AVA, AVD, and AVE command interneurons control backward locomotion. Another interneuron, RIM, sits at a unique position in the locomotion circuitry by forming connections with both forward and backward command interneurons. Interestingly, we found that both activation and inhibition of RIM promote backward locomotion. Further, RIM regulates reversals in a command interneuron-dependent, as well as independent manner. How could RIM have two opposite effects on the same behavioral response? To address this question, we are testing several models, hoping to identify the underlying circuit as well as synaptic and molecular mechanisms.

McGhee JD (1987) Biochemistry "Purification and characterization of a carboxylesterase from the intestine of the nematode Caenorhabditis elegans."

McGhee JD

[Biochemistry, 1987]

The major intestinal esterase from the nematode Caenorhabditis elegans has been purified to essential homogeneity. Starting from whole worms, the overall purification is 9000-fold with a 10% recovery of activity. The esterase is a single polypeptide chain of Mr 60,000 and is stoichiometrically inhibited by organophosphates. Substrate preferences and inhibition patterns classify the enzyme as a carboxylesterase (EC 3.1.1.1), but the physiological function is unknown. The sequence of 13 amino acid residues at the esterase N- terminus has been determined. This partial sequence shows a surprisingly high degree of similarity to the N-terminal sequence of two carboxylesterases recently isolated from Drosophila mojavensis [Pen, J., van Beeumen, J., & Beintema, J. J. (1986) Biochem. J. 238, 691-699].

Murakami S et al. (1999) Curr Biol "Life extension and stress resistance in Caenorhabditis elegans modulated by the tkr-1 gene."

Johnson TE, Murakami S

[Curr Biol, 1999]

In this Brief Communication, which appeared in the 14 September 1998 issue of Current Biology, the UV dose was reported erroneously. The dose reported was 20 J/m2 but the actual dose used was 0.4 J/cm2. Also, the gene formally referred to as tkr-1 has since been renamed old-1 (overexpression longevity determination).

Yeon, Jihye et al. (2021) MicroPubl Biol

Sengupta, Piali, Takeishi, Asuka, Yeon, Jihye

[MicroPubl Biol, 2021]

Neuronal networks can achieve similar outputs via distinct underlying circuit mechanisms (Beverly et al., 2011; Marder et al., 2015; Saideman et al., 2007; Trojanowski et al., 2014; Wang et al., 2019). This degeneracy allows networks to maintain robustness without compromising functional flexibility (Cropper et al., 2016; Edelman and Gally, 2001). Since the contribution of degenerate neuronal pathways is likely to be revealed under defined genetic or environmental conditions, it is challenging to identify and describe the contributions of such pathways to neuronal circuit function.

Ramos CG et al. (2014) J Bacteriol "Retraction for Ramos et al., MtvR is a global small noncoding regulatory RNA in Burkholderia cenocepacia."

Feliciano JR, da Costa PJ, Ramos CG, Grilo AM, Leitao JH

[J Bacteriol, 2014]

Volume 195, no. 16, p. 35143523, 2013. A number of problems related to images published in this paper have been brought to our attention. Figure 1D contains duplicated images in lanes S and LE, and Fig. 4D and 6B contain images previously published in articles in this journal and in Microbiology and Microbial Pathogenesis, i.e., the following: C. G. Ramos, S. A. Sousa, A. M. Grilo, J. R. Feliciano, and J. H. Leitao, J. Bacteriol. 193:15151526, 2011. doi:10.1128/JB.01374-11. S. A. Sousa, C. G. Ramos, L. M. Moreira, and J. H. Leitao, Microbiology 156:896908, 2010. doi:10.1099/mic.0.035139-0. C. G. Ramos, S. A. Sousa, A. M. Grilo, L. Eberl, and J. H. Leitao, Microb. Pathog. 48:168177, 2010. doi: 10.1016/j.micpath.2010.02.006. Therefore, we retract the paper. We deeply regret this situation and apologize for any inconvenience to the editors and readers of Journal of Bacteriology, Microbial Pathogenesis, and Microbiology.

Nillegoda NB et al. (2015) Nature "Crucial HSP70 co-chaperone complex unlocks metazoan protein disaggregation."

Berynskyy M, Morimoto RI, Bukau B, Stengel F, Kirstein J, Szlachcic A, Arnsburg K, Stank A, Scior A, Nillegoda NB, Gao X, Guilbride DL, Aebersold R, Wade RC, Mayer MP

[Nature, 2015]

Protein aggregates are the hallmark of stressed and ageing cells, and characterize several pathophysiological states. Healthy metazoan cells effectively eliminate intracellular protein aggregates, indicating that efficient disaggregation and/or degradation mechanisms exist. However, metazoans lack the key heat-shock protein disaggregase HSP100 of non-metazoan HSP70-dependent protein disaggregation systems, and the human HSP70 system alone, even with the crucial HSP110 nucleotide exchange factor, has poor disaggregation activity in vitro. This unresolved conundrum is central to protein quality control biology. Here we show that synergic cooperation between complexed J-protein co-chaperones of classes A and B unleashes highly efficient protein disaggregation activity in human and nematode HSP70 systems. Metazoan mixed-class J-protein complexes are transient, involve complementary charged regions conserved in the J-domains and carboxy-terminal domains of each J-protein class, and are flexible with respect to subunit composition. Complex formation allows J-proteins to initiate transient higher order chaperone structures involving HSP70 and interacting nucleotide exchange factors. A network of cooperative class A and B J-protein interactions therefore provides the metazoan HSP70 machinery with powerful, flexible, and finely regulatable disaggregase activity and a further level of regulation crucial for cellular protein quality control.

Miller DM et al. (1992) Worm Breeder's Gazette "unc-4 LacZ Expression in A-Type Motor Neurons"

Miller DM, Niemeyer CJ

[Worm Breeder's Gazette, 1992]

unc-4 LacZ expression in A-type motor neurons David M. Miller and Charles J. Niemeyer, Dept. of Cell Biology, Duke Univ. Medical Ctr, Durham, NC 27710

Sommer RJ et al. (1994) Worm Breeder's Gazette "Evolution of Vulva-Formation: Part II: Species With a Central Vulva"

Sommer RJ, Sternberg PW

[Worm Breeder's Gazette, 1994]

Evolution of vulva-formation: Part II: Species with a central vulva Ralf J. Sommer & Paul W. Sternberg, California Institute of Technology, Division of Biology 156-29, Pasadena, CA 91125