Computational Identification of Lysine Glutarylation Sites Using Positive- Unlabeled Learning

Author(s): Zhe Ju*, Shi-Yun Wang

Journal Name: Current Genomics

Volume 21 , Issue 3 , 2020

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Graphical Abstract:


Background: As a new type of protein acylation modification, lysine glutarylation has been found to play a crucial role in metabolic processes and mitochondrial functions. To further explore the biological mechanisms and functions of glutarylation, it is significant to predict the potential glutarylation sites. In the existing glutarylation site predictors, experimentally verified glutarylation sites are treated as positive samples and non-verified lysine sites as the negative samples to train predictors. However, the non-verified lysine sites may contain some glutarylation sites which have not been experimentally identified yet.

Methods: In this study, experimentally verified glutarylation sites are treated as the positive samples, whereas the remaining non-verified lysine sites are treated as unlabeled samples. A bioinformatics tool named PUL-GLU was developed to identify glutarylation sites using a positive-unlabeled learning algorithm.

Results: Experimental results show that PUL-GLU significantly outperforms the current glutarylation site predictors. Therefore, PUL-GLU can be a powerful tool for accurate identification of protein glutarylation sites.

Conclusion: A user-friendly web-server for PUL-GLU is available at

Keywords: Post-translational modification, glutarylation, support vector machine, positive-unlabeled learning, protein acylation, site predictors.

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Article Details

Year: 2020
Published on: 09 July, 2020
Page: [204 - 211]
Pages: 8
DOI: 10.2174/1389202921666200511072327
Price: $65

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