# Discovery of germline genes and regulatory networks in planarians

> **NIH NIH R15** · UNIVERSITY OF MASSACHUSETTS BOSTON · 2024 · $457,500

## Abstract

SUMMARY
Proper development of gametes is crucial for the continuation of sexually reproducing species. To succeed,
germline stem cells that populate the gonads must complete a long developmental process that yields highly
differentiated cells: the sperm and egg. These can come together to form a totipotent zygote capable of
developing into an individual. Thus far, genetic screens in mice, flies, and nematodes, have identified
numerous genes required development of the germline. However, voids remain to be filled in our
understanding of the genetic mechanisms that secure the production of functional gametes. To fill some of
these voids, the proposed line of research will explore a new avenue for discovery of genes involved in
germline development. The planarian flatworm Schmidtea mediterranea is an increasingly popular organism
for stem cell research, which holds great promise as a model for reproductive biology. Planarians have an
unmatched ability to completely regenerate their entire reproductive system, including germline stem cells,
throughout their lifetime. This allows experimental analysis of the entire process of gametogenesis without
being confined to a specific developmental window or limited by potential secondary effects on embryogenesis.
Also relevant is the fact that planarians specify their germline through inductive signals that originate from the
soma, which is also true of mammals but not of fly or nematode research models. Experiments performed as
part of this proposal are expected to reveal conserved pathways that control germ cell development by: 1)
Elucidating the mechanisms that lead to use of alternative cleavage and polyadenylation sites during pre-
mRNA 3’end processing in germ cells compared to soma; 2) Uncovering the connection between nuclear
3’end processing and cytoplasmic polyadenylation in germ cells; and 3) Identifying subtle differences in gene
expression and function between germline stem cells in male and female gonads. Due to availability of
optimized protocols for assessing distribution of gene expression in planarians, ease of maintenance and
induction of systemic specific gene knockdown, as well as availability of molecular markers for virtually every
stage in germline development (and somatic tissues), the expression and function of dozens of genes can be
determined during the award period by research performed in large by undergraduate students. Completion of
this project is important because it will reveal conserved processes involved in development of functional
gametes. Additionally, this work will expose dozens of undergraduate students to meritorious research and
strengthen the research environment at the University of Massachusetts Boston, which are specific goals of
the AREA program.

## Key facts

- **NIH application ID:** 11043719
- **Project number:** 2R15HD082754-04
- **Recipient organization:** UNIVERSITY OF MASSACHUSETTS BOSTON
- **Principal Investigator:** Labib Rouhana
- **Activity code:** R15 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $457,500
- **Award type:** 2
- **Project period:** 2014-09-25 → 2027-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/11043719

## Citation

> US National Institutes of Health, RePORTER application 11043719, Discovery of germline genes and regulatory networks in planarians (2R15HD082754-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/11043719. Licensed CC0.

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