# Cell-Penetrating Aptamers Targeting Sub-Cellular Compartments

> **NIH NIH R01** · MAYO CLINIC ROCHESTER · 2020 · $294,428

## Abstract

Cell-penetrating aptamers targeting sub-cellular compartments
ABSTRACT: An unmet need in modern nanomedicine is a method for efficient delivery of nucleic acids
and related cargo into relevant sub-cellular compartments in living tissues. Upon exposure of cells to
nucleic acids or nucleic acid/cationic lipid complexes, conventional methods result in uptake into membrane-
bound vesicles (still topologically outside of the cell) or indiscriminate membrane fusion. Moreover, many
carrier lipid formulations are toxic and of limited use in vivo. While the power of in vitro selection (SELEX) has
been previously applied to select nucleic acid sequences that bind cells or gain preferential vesicular uptake
into specific cells or tissues, vesicular escape with intracellular targeting has not been envisioned. We have
developed a novel approach to this goal. We apply in vitro selection to identify nucleic acid aptamers that
efficiently enter specific sub-cellular compartments by selecting for sequences that undergo enzymatic
modification dependent on specific intracellular enzyme activities. We show that this "reward" approach
can identify naked DNA aptamers with substantially improved delivery to the cell nucleus (“karyophilic”
aptamers). The method will be extended to identify cell-penetrating aptamers specific for different tissues in
living mice. Rewarding aptamer sequences capable of vesicle escape and sub-cellular compartment delivery
opens a new field of opportunities. In the future it may be possible to extend this reward approach to identify
sequences that target other sub-cellular compartments. Four specific aims are proposed to test the hypotheses
that cell-penetrating DNA aptamers targeting specific sub-cellular compartments can be identified by
selecting molecules modified by organelle-specific enzyme activities, and that such homing aptamers
can efficiently deliver cargo to cells and tissues. Aim 1 will continue our selection of karyophilic (nucleus-
homing) DNA aptamers, setting the stage for the targeting of other sub-cellular compartments. Aim 2 will seek
to understand the mechanism of nuclear delivery of karyophilic DNA aptamers. Aim 3 will explore the ability of
karyophilic DNA aptamers to direct cargo delivery into cells. Aim 4 will extend this reward approach in vivo to
develop a library of tissue-specific karyophilic DNA aptamers in mice.

## Key facts

- **NIH application ID:** 9932459
- **Project number:** 5R01GM128579-03
- **Recipient organization:** MAYO CLINIC ROCHESTER
- **Principal Investigator:** LOUIS JAMES MAHER
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $294,428
- **Award type:** 5
- **Project period:** 2018-09-01 → 2022-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9932459

## Citation

> US National Institutes of Health, RePORTER application 9932459, Cell-Penetrating Aptamers Targeting Sub-Cellular Compartments (5R01GM128579-03). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9932459. Licensed CC0.

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