Our lab's first mature Platynereis dumerilii!

These are 2 of the first 3 mature individuals we got from our lab cultures (grown from larvae over the last few months). We are so excited! Let the injections begin! 

For those who are interested, we actually opted for using spirulina and Sera Micron powders only to feed the cultures, instead of the traditional "organic spinach and fish flakes" regimen. The worms have been growing very well, so I was hopeful everything was fine on this diet, but a part of me was afraid that they may be lacking some important nutrient that is absent in spirulina, and maybe their sexual maturation would be delayed. Well, I am so happy to see that they are maturing right on time. So, we may have simplified Platynereis culturing big time!

See the Twİtter thread about Platynereis for more information on the life cycle (and tragedy!).

Loving Worms

GIF and Eel Pond (background) photo by Ryan Null. Duygu's photo by Aaron Pomerantz. 

Our work on Platynereis cell lineage is published in eLife

Access the article from here.

Cell lineage, cell cycle, and cell fate are tightly associated in developmental processes, but in vivo studies at single-cell resolution showing the intricacies of these associations are rare due to technical limitations. In this study on the marine annelid Platynereis dumerilii, we investigated the lineage of the 4d micromere, using high-resolution long-term live imaging complemented with a live-cell cycle reporter. 4d is the origin of mesodermal lineages and the germline in many spiralians. We traced lineages at single-cell resolution within 4d and demonstrate that embryonic segmental mesoderm forms via teloblastic divisions, as in clitellate annelids. We also identified the precise cellular origins of the larval mesodermal posterior growth zone. We found that differentially-fated progeny of 4d (germline, segmental mesoderm, growth zone) display significantly different cell cycling. This work has evolutionary implications, sets up the foundation for functional studies in annelid stem cells, and presents newly established techniques for live imaging marine embryos.

ML lineage tree indicating known and novel sub-lineages in P. dumerilii, and comparison of P. dumerilii with the leech.