Disruption of catenin‐cadherin interaction decreases tail regeneration in Lumbriculus variegatus.

Lumbriculus variegatus is an aquatic oligochaete that can regenerate new tail segments within two to three weeks of tail removal. While many studies have investigated this ability to regenerate, not much is known about the molecular pathways that are activated during the regeneration process in Lumbriculus . Regeneration of animal tissue must also involve the formation of adherens junctions between new cells in the proliferating tissue. Cadherins are calcium‐dependent adherens molecules that bind adjacent cells together. Cadherins in turn bind to catenins. The β‐catenin has been shown to be important for cell adhesion as well as for the Wnt signaling pathway which influences the polarity of developing organisms. As a first step in determining if β‐catenin is involved in regeneration of new tissue in Lumbriculus , we tested the effect of the β‐catenin inhibitor quercetin, on tail regeneration rate. Low Dose groups were exposed to 25 mM of quercetin and High Dose groups were exposed to 50 mM of quercetin for two weeks. Controls were not exposed to this inhibitor. Results showed that, while all groups experienced tail segment regeneration during the first week of treatment, the rate of regeneration was significantly slower in groups exposed to both low and high doses of quercetin from the second to the fifth day. We suggest that the β‐catenin‐cadherin signaling pathway plays a role in Lumbriculus tissue regeneration.