PT  - JOURNAL ARTICLE
AU  - Julia Ramon Mateu
AU  - Mark Q. Martindale
TI  - Scarless whole-body regeneration in the absence of a blastema requires cell division in the ctenophore <em>Mnemiopsis leidyi</em>
AID  - 10.1101/509331
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 509331
4099  - http://biorxiv.org/content/early/2019/01/02/509331.short
4100  - http://biorxiv.org/content/early/2019/01/02/509331.full
AB  - It has been known for well over 50 years that ctenophores have the capacity to regenerate but the cellular and molecular mechanisms underlying this ability are unknown. We have studied wound healing and adult regeneration in the ctenophore Mnemiopsis leidyi and show that cell proliferation is activated at the wound site and is indispensable for whole-body regeneration. Wound healing occurs normally in the absence of cell proliferation forming a scar-less wound epithelium. No blastema is generated, rather undifferentiated cells assume the correct location of missing structures and differentiate in place. Proliferative cells from the uncut tissue migrate to the wound site and contribute to the formation of new structures. Surprisingly, the ability to regenerate is recovered when exposure to cell-proliferation blocking treatment ends, suggesting that the onset of regeneration is constantly ready to be triggered and it is somehow independent of the wound healing process.