If humans lose their reproductive cells (i.e eggs and sperm) they become infertile. In contrast, some animals regenerate their reproductive cells and reproductive organs. MBL Hibbitt Fellow B. Duygu Özpolat recently received a grant to uncover the mechanisms of reproductive cell and tissue regeneration by identifying the cell types and genes involved in this process. This five-year award from the National Institute of General Medical Sciences/NIH will contribute to fundamental knowledge of reproductive and stem cell biology and will inform regenerative medicine approaches.
Humans and well-established research organisms lack the ability to regenerate their reproductive cells (germ cells) and reproductive organs. Accordingly, research findings from these organisms established the current view that germ cells are a distinct lineage separated from the soma (body cells); therefore, the loss of germ cells renders an organism infertile because the soma cannot generate new ones. Contradicting this widely accepted view is the fact that many organisms (e.g. hydra, flatworms, segmented worms, and sea stars) can readily regenerate germ cells. However, the cellular source of regenerated germ cells in these organisms is very poorly understood. The goal of Özpolat Lab is to close this knowledge gap and define the cellular origins and molecular mechanisms of germ cell regeneration.
Özpolat Lab uses a segmented worm, Platynereis dumerilii, for studying germ cell regeneration. Platynereis is well-suited for this study because germ cell regeneration can be induced and is achieved quickly; transcriptome databases, a draft genome, and transgenic tools (critical for genetic lineage tracing) are available; and a small and transparent body makes it excellent for live imaging. Therefore, Platynereis is a research organism that presents a rare opportunity to combine the modern techniques required to study germ cell regeneration (live-imaging, genetic lineage tracing, transcriptomics) in the relevant post-embryonic life stages (i.e. juveniles, adults) which are typically challenging to image live.
The project, which is funded by a Maximizing Investigators’ Research Award (MIRA) (R35), will significantly contribute to our fundamental understanding of germ cell biology and the soma-germ cell distinction.
Photo: The segmented worm Platynereis dumerilii.Credit: Ryan Null