TY  - GEN
T1  - Lipopolysaccharide stimulates egg laying in Caenorhabditis elegans
AU  - Leung, Angela Ching-Yee
AU  - Hughes, Catherine
AU  - Gunderson, Jakob
AU  - Lee, Myeongwoo
DO  - 10.17912/micropub.biology.000308
UR  - http://beta.micropublication.org/journals/biology/micropub-biology-000308/
AB  - Caenorhabditis elegans is fed with the unharmful bacterial food of Escherichia coli strain OP50 in the laboratory but the nematode is also susceptible to infections by ingested Gram-negative bacterial pathogens. Salmonella enterica invades epithelial cells, causes germline cell death, and kills the worm in as short as two days, while E. coli OP50 does not result in any worm death for at least four days (Aballay et al. 2003; Tenor et al. 2004). When the worms are allowed to grow into 1-day-old adults on a lawn of S. enterica, the expression of an innate response gene, PMK-1, is activated, indicating infection by the pathogen and the elicited innate response of the host (Tenor et al. 2004). Here we report that lipopolysaccharide (LPS) extracted from S. enterica stimulated gravid adults to lay more eggs in LPS-containing solution than those in M9 buffer only. Figure 1 shows that the worms that were exposed to 0.1 mg/ml LPS for 1 hour laid an average of 5.57±0.57 eggs (± one standard error; n = 101), which was significantly different (p < 0.0001) than the response of the worms exposed to M9 buffer (1.87±0.25 eggs; n = 112). Serotonin, produced by the hermaphrodite-specific neurons (HSNs), is a known stimulant of the vulval muscle contractions that induce egg laying (Trent et al. 1983). Therefore, we used serotonin in this study as a positive control condition, and the egg-laying level that it induced as a reference to that caused by LPS. Exogenous serotonin at 1 mg/ml in M9 resulted in the laying of 8.40±0.60 eggs in one hour (n = 111; p < 0.0001 compared to the worms in M9). The magnitude of LPS-stimulated egg laying was not comparable to that of the serotonin one (p = 0.0005, indicating significant difference).
PY  - 2020
JO  - microPublication Biology
ER  -