Single-cell transcriptome reveals the novel role of T-bet in suppressing the immature NK gene signature
Abstract
The transcriptional activation and repression during NK cell ontology are poorly understood. Here, using single-cell RNA-sequencing, we reveal a novel role for T-bet in suppressing the immature gene signature during murine NK cell development. Based on transcriptome, we identified five distinct NK cell clusters and define their relative developmental maturity in the bone marrow. Transcriptome-based machine-learning classifiers revealed that half of the mTORC2-deficient NK cells belongs to the least mature NK cluster. Mechanistically, loss of mTORC2 results in an increased expression of signature genes representing immature NK cells. Since mTORC2 regulates the expression of T-bet through AktS473-FoxO1 axis, we further characterized the T-bet-deficient NK cells and found an augmented immature transcriptomic signature. Moreover, deletion of Foxo1 restores the expression of T-bet and corrects the abnormal expression of immature NK genes. Collectively, our study reveals a novel role for mTORC2-AktS473-FoxO1-T-bet axis in suppressing the transcriptional signature of immature NK cells.
Data availability
Sequencing data have been deposited in GEO under accession code GSE150166
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mTORC1 and mTORC2 differentially regulate NK cell developmentNCBI SRA BioSample database, PRJNA434424.
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Developmental Acquisition of Regulomes Underlies Innate Lymphoid Cell FunctionalityNCBI Gene Expression Omnibus, GSE77695.
Article and author information
Author details
Funding
National Institutes of Health (AI102893)
- Subramaniam Malarkannan
National Cancer Institute (CA179363)
- Subramaniam Malarkannan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Florent Ginhoux, Agency for Science Technology and Research, Singapore
Ethics
Animal experimentation: All mice were maintained in pathogen-free conditions in the Biological Resource Center at the Medical College of Wisconsin. All animal protocols were approved by Institutional Animal Care and Use Committees. The unique animal protocols that are approved by the IACUC and used in this study is: AUA1512.
Version history
- Received: August 25, 2019
- Accepted: May 8, 2020
- Accepted Manuscript published: May 14, 2020 (version 1)
- Version of Record published: May 28, 2020 (version 2)
Copyright
© 2020, Yang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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