arXiv Machine Learning

ProMORNA: An End-to-End Generative Framework for Full-Length mRNA Design

arXiv AI
Oct 5

Predictor-Guided Latent Space Codon Optimization for Maximizing Protein Expression

Predictor-Guided Latent Space Codon Optimization (LSCO) transforms the discrete codon selection problem into a continuous optimization task by embedding sequences into the latent space of a pretrained mRNA language model, allowing gradient-based search. LSCO integrates a data-driven expression objective from an uncertainty-aware predictor, a Minimum-Free-Energy regularizer for structural stability, a naturalness prior derived from a protein-to-codon back-translation model, and constrained decoding to preserve protein fidelity. In a real-world wet-lab antibody expression dataset, LSCO outperforms both simple frequency-based methods and modern deep generative baselines in predicted expression while maintaining appropriate biophysical properties.

By Alberto Caron, Tianyu Cui, Dmytro S. Lituiev, Mangal Prakash, Artem Moskalev, Amina Mollaysa, Bo Zhai, Hirsh Nanda, Daniel M. Poole, Zhongyin Liu, Iman Farasat, Robert Davidson, Nikolay V. Manyakov, Tommaso Mansi, Scott Oloff, Rui Liao
arXiv Machine Learning
Oct 12

MORAD: Reinforcement Learning with Multi-Objective Rewards for RNA Inverse Design

MORAD is an online reinforcement learning framework that trains a single shared policy for backbone‑conditioned RNA diffusion models, enabling structure‑conditioned RNA inverse design across diverse target backbones. It integrates backbone‑conditioned group sampling, group‑relative reward normalization, and a forward‑process diffusion objective, jointly optimizing six measurements—including tertiary geometry, base pairing, ensemble behavior, and sequence composition—by mapping each to a bounded desirability score and combining them with a weighted geometric mean. Compared to a tertiary‑structure‑only reward, MORAD improves 10 of 11 evaluation metrics, achieving significant gains in GDT‑TS, pairing MCC, and normalized ensemble defect, and surpasses existing methods such as RiboDiffusion, gRNAde, and RDesign on tertiary structural accuracy, secondary‑structure pairing, and thermodynamic quality.

By Jixin Tang, Ji Guo, Jun Zhao
arXiv Machine Learning
Oct 12

Scaling RNA Foundation Models through Iterative Refinement

Eco‑RNA is an 80‑million‑parameter RNA foundation model that introduces adjustable inference depth via learned iterative refinement. The shared, input‑conditioned Transformer core repeatedly refines sequence representations, with the number of iterations chosen after training to control effective depth. On the RNAGym fitness benchmark, increasing iterations from one to four improves Spearman correlation from 0.242 to 0.286, and at four iterations Eco‑RNA outperforms the 40‑billion‑parameter Evo 2 model across all aggregate fitness metrics, while also excelling in non‑coding RNA classification, secondary‑structure prediction, and chemical probing profile prediction.

By Pengan Chen, Liang Hong, Xinyuan Liu, Han Huang, Ziqian Lin, Jiayang Chen, Yimin Fan, Jiyue Jiang, Yu Li
arXiv AI
Oct 2

Pepti-drift: Scalable Safe-Active Peptide Generation Without Inference-Time Guidance

Pepti-drift is a one‑step peptide generation framework that uses a single latent refinement and parallel decoding, avoiding costly inference‑time guidance. It incorporates attraction toward target‑specific binders and repulsion from liability‑associated regions, achieving an 18.37% predicted Safe‑Active yield across 88 held‑out targets. The method delivers competitive gains to multi‑property‑guided baselines while reducing generation cost by 468×, enabling scalable and fair high‑throughput peptide design.

By Takashi Fujiwara, Hikaru Shindo, Kaushalya Madhawa, Jun Jin Choong, Shuan Chen, Yuna Oikawa, Yiming Zhang, Gyubok Lee, Keisuke Ozawa
arXiv Machine Learning
6d ago

Noise-Space Reward Alignment for Few-Step Generative Models

The paper introduces Noise Policy Optimization (NPO), a method for aligning few-step generative models with black-box reward signals. NPO learns an amortized flow policy that transforms initial Gaussian noise into a reward-tilted distribution, allowing the pretrained generator to produce higher-reward outputs without fine-tuning. The approach achieves superior reward-quality trade-offs across image, language, and protein generation tasks while drastically reducing inference cost compared to test-time search methods.

By Woocheol Shin, Taeyoung Yun, Jiwon Sung, Hyeongyu Kang, Jeongmin Park, Jaewoo Lee, Kyuil Sim, Dohyun Kim, Yutong He, Jinkyoo Park
arXiv Machine Learning
Oct 12

Designing Protein Structures from Natural Language

The paper introduces Prompteina, an all‑atom protein structure generation model that accepts natural‑language descriptions of desired structural and functional properties, similar to text‑to‑image systems. It is trained on a large paired dataset of 1.8 million protein structures and over 50 million captions, and fine‑tuned from the Proteina‑Complexa model to align residues with textual cues. Prompteina outperforms existing baselines on most structural metrics, improves binder design performance, and experimentally validates nine new binders for the GM2A target.

By Joseph Lee, Yanjing Li, Bo Qiang, Gregory Lau, Allyson Ettinger, Noah A. Smith, Rory Donovan-Maiye, David Baker, Hanna Hajishirzi, Pang Wei Koh