# Data-Driven Design of PROTAC Linkers to Improve PROTAC Cell Membrane Permeability

**Authors:** Yuki Murakami, Shoichi Ishida, Nobuo Cho, Hitomi Yuki, Masateru Ohta, Teruki Honma, Yosuke Demizu, Kei Terayama

PMC · DOI: 10.1021/jacsau.6c00033 · JACS Au · 2026-02-09

## TL;DR

This paper introduces a new method to design PROTAC linkers that improve cell membrane permeability using machine learning and reinforcement learning.

## Contribution

The novel contribution is a generative model, PROTAC-TS, that explicitly optimizes PROTAC linkers for cell membrane permeability.

## Key findings

- A cell membrane permeability prediction model achieved high accuracy (R² = 0.710).
- PROTAC-TS successfully generated linkers with high predicted permeability and PROTAC likeness.

## Abstract

Proteolysis-targeting
chimeras (PROTACs) are promising next-generation
therapeutics for the degradation of disease-associated proteins. However,
optimizing the physicochemical properties of PROTACs, particularly
their poor cell membrane permeability, remains challenging. Traditionally,
PROTAC linkers have been manually designed to improve cell membrane
permeability. Although recent machine learning-based approaches have
enabled the rational design of PROTAC linkers, no linker design methods
that explicitly address cell membrane permeability have been reported.
In this study, we developed PROTAC-TS, a linker generative model that
combines a chemical language model and reinforcement learning to control
cell membrane permeability. We first constructed a prediction model
of cell membrane permeability, which achieved high prediction performance
(R
2 = 0.710). By integrating this prediction
model into the generative model, we successfully designed linkers
of PROTACs with high predicted cell membrane permeability while considering
PROTAC likeness. Our results highlight the potential of PROTAC-TS
in accelerating PROTAC development with favorable cell membrane permeability.

## Full-text entities

- **Genes:** BRD4 (bromodomain containing 4) [NCBI Gene 23476] {aka CAP, CDLS6, FSHRG4, HUNK1, HUNKI, MCAP}, ALK (ALK receptor tyrosine kinase) [NCBI Gene 238] {aka ALK1, CD246, NBLST3}, VHL (von Hippel-Lindau tumor suppressor) [NCBI Gene 7428] {aka HRCA1, RCA1, VHL1, pVHL}, IRAK4 (interleukin 1 receptor associated kinase 4) [NCBI Gene 51135] {aka IMD67, IPD1, IRAK-4, NY-REN-64, REN64}, BTK (Bruton tyrosine kinase) [NCBI Gene 695] {aka AGMX1, AT, ATK, BPK, IGHD3, IMD1}, CRBN (cereblon) [NCBI Gene 51185] {aka MRT2, MRT2A}
- **Diseases:** toxicity (MESH:D064420)
- **Chemicals:** TS (MESH:D014316), methanol (MESH:D000432), ARV-771 (MESH:C000720760), polyethylene glycol (MESH:D011092), acetonitrile (MESH:C032159), esters (MESH:D004952), alkane (MESH:D000473), thalidomide (MESH:D013792), HBSS (-), Lucifer yellow (MESH:C017475), dBET6 (MESH:C000720891), hydrogen (MESH:D006859)
- **Cell lines:** Madin-Darby canine — Canis lupus familiaris (Dog), Spontaneously immortalized cell line (CVCL_0422), Caco-2 — Homo sapiens (Human), Colon adenocarcinoma, Cancer cell line (CVCL_0025)

## Full text

_Full body text omitted from this summary view._ Fetch the complete paper as Markdown: https://tomesphere.com/paper/PMC12933330/full.md

## Figures

6 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12933330/full.md

## References

65 references — full list in the complete paper: https://tomesphere.com/paper/PMC12933330/full.md

---
Source: https://tomesphere.com/paper/PMC12933330