# The Real Immortal Jellyfish

> Research site for *Turritopsis dohrnii*, the "immortal jellyfish" — the only known animal able to
> reverse its life cycle indefinitely, transforming from an adult medusa back into a juvenile polyp
> through cell transdifferentiation. Maintained by the Miglietta Lab at Texas A&M University at Galveston.

## Key facts

- Species: *Turritopsis dohrnii* (Cnidaria, Hydrozoa), described from Italy in 1883.
- Its reversible life cycle was first described by Bavestrello et al. in 1992.
- When starved or damaged, the medusa settles, passes through a cyst stage, and metamorphoses back
  into a polyp. This reverse development takes roughly 48-72 hours.
- During reversal, mature somatic cells transdifferentiate into new cell types, which makes the
  species a candidate in vivo model for cell reprogramming and regenerative research.
- Tropical populations carry about 8 tentacles throughout life; temperate populations reach up to 24.
- It is now a globally introduced marine species, likely spread through ship ballast water, recorded
  in the Mediterranean, Japan, Panama (Pacific and Atlantic), Brazil, the Gulf of Mexico, Turkey,
  and California.
- Research is funded by the National Science Foundation: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1936565

## Pages

- [Home](https://therealimmortaljellyfish.com/): Biology, life cycle, ecology, and genome study overview.
- [Research](https://therealimmortaljellyfish.com/research/): NSF-funded project on transcriptome assembly, draft genome, and differential gene expression.
- [Publications](https://therealimmortaljellyfish.com/publications/): Peer-reviewed papers from the lab and other groups.
- [Data](https://therealimmortaljellyfish.com/data/): Downloadable transcriptome assemblies, GFF annotations, and NCBI records.
- [Media](https://therealimmortaljellyfish.com/media/): Press, broadcast, and podcast coverage.
- [Scientists](https://therealimmortaljellyfish.com/scientists/): Lab members and alumni.
- [Photo Gallery](https://therealimmortaljellyfish.com/gallery/): Credited photographs of medusae, polyps, and cysts.
- [Contact](https://therealimmortaljellyfish.com/contact/): Enquiry form and lab address.

## People

- Dr. Maria Pia Miglietta, Ph.D., Texas A&M University at Galveston
- Yui Matsumoto, Ph.D. — Transcriptomics Consultant and Analyst at OmniTier
- Juliana Giraldo, Ph.D. — Ph.D. Student, Texas A&M University

## Publications

- Cellular Reprogramming and Immortality: Expression Profiling Reveals Putative Genes Involved in Turritopsis dohrnii s Life Cycle Reversal. *Genome Biology and Evolution*, 2021. https://doi.org/10.1093/gbe/evab136
- Nontraditional systems in aging research: an update. *Cellular and Molecular Life Sciences*, 2020.
- Phylogenetics and species delimitation of two hydrozoa (phylum Cnidaria): Turritopsis. *Marine Biodiversity*, 2019. https://link.springer.com/article/10.1007/s12526-018-0891-8
- Transcriptome Characterization of Reverse Development in Turritopsis dohrnii (Hydrozoa, Cnidaria). *Genes, Genomes, Genetics*, 2019. https://doi.org/10.1534/g3.119.400487
- An Integrative Identification Guide to the Hydrozoa (Cnidaria) of Bocas del Toro, Panama. *Neotropical Biodiversity*, 2018. https://www.tandfonline.com/doi/full/10.1080/23766808.2018.1488656
- Complete mitochondrial genome and evolutionary analysis of Turritopsis dohrnii, the  immortal  jellyfish with a reversible life-cycle. *Molecular Phylogenetics and Evolution*, 2017. https://www.sciencedirect.com/science/article/pii/S1055790316303359
- A Silent Invasion. *Biological Invasions*, 2009. https://link.springer.com/article/10.1007/s10530-008-9296-0
- Induction of reverse development in two marine Hydrozoans. *International Journal of Developmental Biology*, 2007. https://pubmed.ncbi.nlm.nih.gov/17183464/
- Species in the genus Turritopsis (Cnidaria, Hydrozoa): A molecular evaluation. *Journal of Zoological Systematics and Evolutionary Research*, 2006. https://onlinelibrary.wiley.com/doi/full/10.1111/j.1439-0469.2006.00379.x
- Reverse development in Cnidaria. *Canadian Journal of Zoology*, 2004. https://www.researchgate.net/publication/249542511_Reverse_development_in_Cnidaria
- Morphological and ultrastructural analysis of Turritopsis nutricula during life cycle reversal. *Tissue and Cell*, 2003. https://pubmed.ncbi.nlm.nih.gov/12798130/
- Reversing the Life Cycle: Medusae Transforming into Polyps and Cell Transdifferentiation in Turritopsis nutricula (Cnidaria, Hydrozoa). *The Biological Bulletin*, 1996. https://www.journals.uchicago.edu/doi/abs/10.2307/1543022
- Transdifferentiation in Medusae. *International Review of Cytology*, 1992. https://www.sciencedirect.com/science/article/abs/pii/S0074769608613008
- Transdifferentiation and regeneration in vitro. *Developmental Biology*, 1982. https://www.sciencedirect.com/science/article/abs/pii/0012160682901932

## Data downloads

- Assembled transcriptome (gzipped FASTA) and GFF annotations covering the colonial polyp, newborn
  medusa, cyst, and reversed polyp stages. See https://therealimmortaljellyfish.com/data/
- Raw RNA-seq records are deposited at NCBI BioSample.

## Selected media coverage

- Nodding our Tusks to Heroic Mutations — Genome BC: https://omny.fm/shows/nice-genes/nodding-our-tusks-to-heroic-mutations
- Stayin  Alive: How the Immortal Jellyfish Cheats Death — New York Times: https://www.nytimes.com/2022/05/11/learning/stayin-alive-how-the-immortal-jellyfish-cheats-death.html
- These jellyfish seem to cheat death. What s their secret? — Popular Science Magazine: https://www.popsci.com/story/animals/tales-jellyfish-reverse-aging/
- This Jellyfish Can Defy Death And Turn Back Time — KSAT 12 News: https://www.ksat.com/news/local/2021/03/16/this-jellyfish-can-defy-death-and-turn-back-time/
- This Jellyfish Can Defy Death And Turn Back Time — Environmental News Network: https://www.enn.com/articles/67311-this-jellyfish-can-defy-death-and-turn-back-time
- Is this sea creature a fountain of youth? Texas A M at Galveston investigates — 25 News KXXV: https://www.kxxv.com/news/local-news/is-this-sea-creature-a-fountain-of-youth-texas-a-m-at-galveston-investigates
- Around Texas with John Sharp: Oceans (Season 1, Episode 2) — PBS: https://www.pbs.org/video/oceans-8dobwk/
- The secrets of the immortal jellyfish, Earth s longest-living animal — BBC Science Focus Magazine: https://www.sciencefocus.com/nature/immortal-jellyfish/
- Audacious Little Things: Elevation by Reduction — NPR Connecticut: https://www.wnpr.org/post/audacious-little-things-elevation-reduction
- Tiny Things. Big Impact! — Texas A M Research Magazine: https://tamuresearch.foleon.com/research-at-tamu-magazine/spring2021/tiny-things-big-impact/
- La medusa immortale — Josway: https://josway.it/la-medusa-immortale/
- Les méduses peuvent défier la mort et remonter le temps — 45 Secondes L actualité Numérique: https://45secondes.fr/les-meduses-peuvent-defier-la-mort-et-remonter-le-temps-la-renaissance-automatique-peut-faire-la-mort-et-avancer-dans-le-mouvement-dans-le-passe/

## Contact

Miglietta Lab, Department of Marine Biology, Texas A&M University at Galveston
200 Seawolf Parkway, bldg. 3029, Galveston, TX 77553
https://www.tamug.edu/miglietta/