Braeckman BP et al. (2002) Aging Cell "Rebuttal to Van Voorhies: 'the influence of metabolic rate on longevity in the nematode Caenorhabditis elegans'."

Braeckman BP, Houthoofd K, Vanfleteren JR

[Aging Cell, 2002]

The papers by Van Voorhies in Free Radical Biology & Medicine (33, 587-596, 2002) and in this journal claim that the major longevity-extending mutations in C. elegans essentially act by reducing metabolic rate as predicted by the rate-of-living theory, and do not alter any metabolically independent mechanism specific to aging. In contrast, we found no evidence of a reduction in metabolic rate in these mutants using different experimental approaches. Now, Van Voorhies challenges the accuracy of our experimental results.

Dehn AS et al. (2022) PLoS Biol "Binucleation ramps up gene expression meeting the physiological demands of an organism."

Dehn AS, Losick VP

[PLoS Biol, 2022]

In this issue of PLOS Biology, van Rijnberk and colleagues show how polyploidy, via binucleation, enables Caenorhabditis elegans intestinal cells to ramp up gene expression supplying the oocytes with the necessary lipids for optimal organismal growth and reproductive fitness.

Sendinc E et al. (2015) Cell "Remodeling Your Way out of Cell Cycle."

Sendinc E, Shi Y, Jambhekar A

[Cell, 2015]

Throughout development, proliferative progenitors lose their mitotic potential, exit the cell cycle, and differentiate. In this issue, Ruijtenberg and van den Heuvel identify an important lineage-specific role for a SWI/SNF chromatin-remodeling complex that collaborates with core cell-cycle regulators to promote cell-cycle exit and terminal muscle cell differentiation.

Partridge L et al. (1992) Nature "Evolutionary biology. What the sperm count costs."

Partridge L, Harvey PH

[Nature, 1992]

Dissecting the sex life of the nematode worm Caenorhabditis elegans has already provided surprises for biologists interested in life-history theory. In a report on page 456 of this issue, Van Voorhies throws another spanner in the works by demonstrating that the costs of producing sperm are not as negligible as we might have thought.

Ma L et al. (2020) J Cell Biol "Membrane fusion drives pronuclear meeting in the one-cell embryo."

Starr DA, Ma L

[J Cell Biol, 2020]

The mechanisms that control how the two parental pronuclei fuse in the first mitosis of the embryo are poorly understood. In this issue, Rahman et al. (2020. J. Cell Biol.https://doi.org/10.1083/jcb.201909137) found that membrane fusion between pronuclear envelopes, followed by fenestration, promotes pronuclear fusion.

Kumsta C et al. (2019) J Cell Biol "Getting under the skin: Cuticle damage elicits systemic autophagy response in C. elegans."

Hansen M, Kumsta C

[J Cell Biol, 2019]

In this issue, Zhang et al. (2019. <i>J. Cell. Biol.</i> https://doi.org/10.1083/jcb.201907196) describe a molecular mechanism by which cuticular damage in the nematode <i>C. elegans</i> leads to systemic induction of autophagy by signals propagated from sensory neurons via the TGF- signaling pathway.

Hickson GRX (2022) J Cell Biol "A back-up source of microtubules for the midbody during cytokinesis."

Hickson GRX

[J Cell Biol, 2022]

During cytokinesis, microtubules become compacted into a dense midbody prior to abscission. Using genetic perturbations and imaging of C. elegans zygotes, Hirsch et al. (2022. J. Cell Biol.https://doi.org/10.1083/jcb.202011085) uncover an unexpected source of microtubules that can populate the midbody when central spindle microtubules are missing.

Little P (1992) Nature "DNA sequencing. The worm turns and delivers."

Little P

[Nature, 1992]

Supporters of large DNA sequencing projects will take heart (and find much to learn) from the report by J. Sulston and colleagues that appears on page 37 of this issue. Sulston et al. describe the first results of the Caenorhabditis elegans genome sequencing project, and have come up with not only hitherto unknown genes but also with fresh and biologically relevant information.

Van Voorhies WA (2002) Aging Cell "Rebuttal to Braeckman et al: 'Assessing metabolic activity in again Caenorhabditis elegans: concepts and controversies'."

Van Voorhies WA

[Aging Cell, 2002]

The reviews by Braechman et al. and Van Voorhies in this issue of Aging Cell concur on the potential importance of metabolic rate and function to longevity in C. elegans. These reviews differ though, on their assessment of whether long-lived C. elegans mutants have a reduced metabolic rate compared to wild-type worms. At the centre of this disagreement are two main issues: the importance of measurement conditions when conducting metabolic assays on C. elegans, and which techniques are appropriate for measuring the metabolic rate of an organism and subsequent analysis of such data. These issues are interconnected; if the conditions under which an organism's metabolic rate are measured have a large impact on the resulting data, conclusions drawn from data collected from animals under different conditions may be invalid irrespective of the validity of the measurement methods. Conversely, measurement techniques which produce spurious data cannot be used to draw accurate conclusions about the metabolic rate of an organism, regardless of the conditions under which the organism was maintained.

Garrity PA (2007) J Neurophysiol "Role of adaptation in C. elegans thermotaxis. Focus on "Short-term adaptation and temporal processing in the cryophilic response of Caenorabditis elegans"."

Garrity PA

[J Neurophysiol, 2007]

The work of Clark et al. in this issue of J. Neurophysiology extends the analysis of thermotaxis in C. elegans by providing a detailed analysis of the adaptation of thermotactic behavior. Previous work indicates that thermotaxis in C. elegans involves a biased random walk in which changes in temperature alter the duration of the runs that an animal makes between turns. Interestingly, the authors find that although behavioral responses to increases and decreases in temperature have opposite effects on run length, the two responses are of similar magnitude and adapt with similar kinetics. These properties are predicted to allow the system act as a band-pass filter that would be less sensitive to temperature fluctuations occurring on a time-scale significantly faster or slower than the time needed for an average run. This analysis of C. elegans thermotaxis raises potential parallels to bacterial chemotaxis, with the kinetics of adaptation playing an important role in determining the ability of the organism to sense a stimulus gradient. This raises the possibility that diverse organisms may exploit similar system properties to solve similar problems, such as the problem of responding robustly to subtle gradations in an external stimulus.