# Novel insights from a divergent form of germ plasm

> **NIH NIH R01** · UNIVERSITY OF ILLINOIS AT CHICAGO · 2022 · $306,452

## Abstract

Ribonucleoproteins (RNPs) are crucial elements in many biological processes and cell
types. The polar granules of Drosophila melanogaster have long served as a model
system for understanding the functions of RNPs. Polar granules are small,
heterogeneous RNPs that specify the primordial germ cells in the fly. In this proposal, we
will build upon the Drosophila knowledge using our wasp model system Nasonia
vitripennis. The Nasonia equivalent of the polar granules is in the form of a large,
spherical, solid RNP called the oosome. This is in contrast to the polar granules, which
take the form of many small particles localized to the posterior pole of the embryo. The
Nasonia oosome undergoes a dramatic migration within the posterior half of the embryo,
a process which has not counterpart in Drosophila. Finally, the oosome is extruded in
one very large bud that will divide and give rise to the pole cells. This is in strong
contrast to pole cell formation in Drosophila, which is driven by the migration of nuclei to
the posterior cortex, where individual cells form from small buds individually. The goal of
this proposal is to understand the molecular and mechanistic properties of the oosome
that are the basis for its morphological and functional differences from the polar
granules. We will characterize the protein composition of the oosome, detail how
translation is regulated within the oosome, and reveal how mRNAs and proteins are
distributed throughout the oosome. We will then identify the interactions among proteins
that may be important for the unique structure and function of the oosome. Finally, we
will take in depth approaches to characterize the functions of novel components of the
oosome. At the conclusion of this project, we will have a mechanistic understanding how
the composition of the oosome and the interactions among the component molecules
give rise to a novel form of RNP.

## Key facts

- **NIH application ID:** 10370321
- **Project number:** 5R01GM129153-04
- **Recipient organization:** UNIVERSITY OF ILLINOIS AT CHICAGO
- **Principal Investigator:** Alexey Arkov
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $306,452
- **Award type:** 5
- **Project period:** 2019-04-01 → 2024-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10370321

## Citation

> US National Institutes of Health, RePORTER application 10370321, Novel insights from a divergent form of germ plasm (5R01GM129153-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10370321. Licensed CC0.

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