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Title: Cross-modality and self-supervised protein embedding for compound–protein affinity and contact prediction
Abstract Motivation

Computational methods for compound–protein affinity and contact (CPAC) prediction aim at facilitating rational drug discovery by simultaneous prediction of the strength and the pattern of compound–protein interactions. Although the desired outputs are highly structure-dependent, the lack of protein structures often makes structure-free methods rely on protein sequence inputs alone. The scarcity of compound–protein pairs with affinity and contact labels further limits the accuracy and the generalizability of CPAC models.

Results

To overcome the aforementioned challenges of structure naivety and labeled-data scarcity, we introduce cross-modality and self-supervised learning, respectively, for structure-aware and task-relevant protein embedding. Specifically, protein data are available in both modalities of 1D amino-acid sequences and predicted 2D contact maps that are separately embedded with recurrent and graph neural networks, respectively, as well as jointly embedded with two cross-modality schemes. Furthermore, both protein modalities are pre-trained under various self-supervised learning strategies, by leveraging massive amount of unlabeled protein data. Our results indicate that individual protein modalities differ in their strengths of predicting affinities or contacts. Proper cross-modality protein embedding combined with self-supervised learning improves model generalizability when predicting both affinities and contacts for unseen proteins.

Availability and implementation

Data and source codes are available at https://github.com/Shen-Lab/CPAC.

Supplementary information

Supplementary data are more » available at Bioinformatics online.

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Authors:
;
Publication Date:
NSF-PAR ID:
10372103
Journal Name:
Bioinformatics
Volume:
38
Issue:
Supplement_2
Page Range or eLocation-ID:
p. ii68-ii74
ISSN:
1367-4803
Publisher:
Oxford University Press
Sponsoring Org:
National Science Foundation
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