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bioRxiv · 10.1101/2021.07.14.452366

Ing4-deficiency enhances HSC quiescence and confers resistance to inflammatory stress

Thompson, Z.·Anderson, G. A.·Rodriguez, M.·Gabriel, S.·Binder, V.·Taylor, A. M.·Kathrein, K. L.
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Abstract

Hematopoiesis is tightly regulated by a network of transcription factors and complexes that are required for the development and maintenance of hematopoietic stem cells (HSCs). We recently identified the tumor suppressor, Ing4, as a critical regulator of HSC homeostasis. Though the Ing4 mechanism of action remains poorly characterized, it has been shown to promote stem-like cell characteristics in malignant cells. This activity is, in part, due to Ing4 mediated regulation of several major signaling pathways, including NF-{kappa}B and c-Myc. In murine hematopoiesis, Ing4 deficiency induces G0 arrest in HSCs, while simultaneously promoting gene expression signatures associated with differentiation. This results in a poised state for Ing4-deficient HSCs. Long term HSCs are unable to overcome this block, but short-term HSCs convert the poised state into regenerative capacity during hematopoietic challenges, including irradiation and transplantation. Overall, our findings suggest that Ing4 plays a crucial role in the regulation of hematopoiesis. Our model provides key tools for further identification and characterization of pathways that control quiescence and differentiation in HSCs.

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Thompson, Z., Anderson, G. A., Rodriguez, M., Gabriel, S., Binder, V., Taylor, A. M., Kathrein, K. L.. 2021-07-15. Ing4-deficiency enhances HSC quiescence and confers resistance to inflammatory stress. https://doi.org/10.1101/2021.07.14.452366

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