The nematode Caenorhabditis elegans and the terrestrial isopod Porcellio scaber likely interact opportunistically

Abstract

Phoresy is a behavior in which an organism, the phoront, travels from one location to another by 'hitching a ride' on the body of a host as it disperses. Some phoronts are generalists, taking advantage of any available host. Others are specialists and travel only when specific hosts are located using chemical cues to identify and move (chemotax) toward the preferred host. Free-living nematodes, like Caenorhabditis elegans, are often found in natural environments that contain terrestrial isopods and other invertebrates. Additionally, the C. elegans wild strain PB306 was isolated associated with the isopod Porcellio scaber. However, it is currently unclear if C. elegans is a phoront of terrestrial isopods, and if so, whether it is a specialist, generalist, or developmental stage-specific combination of both strategies. Because the relevant chemical stimuli might be secreted compounds or volatile odorants, we used different types of chemotaxis assays across diverse extractions of compounds or odorants to test whether C. elegans is attracted to P. scaber. We show that two different strains-the wild isolate PB306 and the laboratory-adapted strain N2-are not attracted to P. scaber during either the dauer or adult life stages. Our results indicate that C. elegans was not attracted to chemical compounds or volatile odorants from P. scaber, providing valuable empirical evidence to suggest that any associations between these two species are likely opportunistic rather than specific phoresy.

Nematode biphasic ‘boom and bust’ dynamics are dependent on host bacterial load while linking dauer and mouth‐form polyphenisms

“…The foundational microbiome and habitat bacteria can support or hinder worm growth, in addition to aiding in host immunity by protecting against infection (Zhang et al, 2017;Montalvo-Katz et al, 2013). However, these studies are somewhat limited in complexity because C. elegans lack tight host associations (Archer et al, 2020).…”

“…However, these studies are somewhat limited in complexity because C . elegans lack tight host associations (Archer et al ., 2020).…”

The nematode Caenorhabditis elegans and diverse potential invertebrate vectors predominantly interact opportunistically

“…wash. However, a dose-dependent attraction of C. elegans to the isopod P. scaber was not detected (Archer et al, 2020). Drosophila occurs in the natural habitat of C. elegans and can disperse nictating C. elegans dauer larvae, but not non-dauer stages, under laboratory conditions (Lee et al, 2012).…”

“…It is known that C. elegans responds to chemical signals from food bacteria and pathogens (Pastan and Perlman, 1971;Ward, 1973;Andrew and Nicholas, 1976;Grewal and Wright, 1992;Schulenburg and Müller, 2004), but little research has been done to determine whether C. elegans can sense potential invertebrate vectors and move toward them (Dillman et al, 2012;Lee et al, 2017;Archer et al, 2020). This would be a prerequisite for C. elegans-initiated migration using invertebrates in response to food shortages or overpopulation.…”

“…This would be a prerequisite for C. elegans-initiated migration using invertebrates in response to food shortages or overpopulation. Previous studies suggest that C. elegans and the terrestrial isopod Porcellio scaber likely interact opportunistically (Archer et al, 2020). Information on the nature of interactions with other migration partners is scarce (Dillman et al, 2012;Lee et al, 2012Lee et al, , 2017.…”