The BH3-only proteins BIM and PUMA are not critical for the reticulocyte apoptosis caused by loss of the pro-survival protein BCL-XL

Delbridge, AR; Aubrey, BJ; Hyland, C; Bernardini, JP; Di Rago, L; GARNIER, JM; Lessene, G; Strasser, A; Alexander, WS; Grabow, S

Author(s): Delbridge, AR; Aubrey, BJ; Hyland, C; Bernardini, JP; Di Rago, L; GARNIER, JM; Lessene, G; Strasser, A; Alexander, WS; Grabow, S;
Details: Publication Year 2017-07-06,Volume 8,Issue #7,Page e2914
Journal Title: Cell Death & Disease
Publication Type: Journal Article
Abstract: Anaemia is a major global health problem arising from diverse causes and for which improved therapeutic strategies are needed. Erythroid cells can undergo apoptotic cell death and loss of pro-survival BCL-XL is known to trigger apoptosis during late-stage erythroid development. However, the mechanism by which loss or pharmacological blockade of BCL-XL leads to erythroid cell apoptosis remains unclear. Here we sought to identify the precise stage of erythropoiesis that depends on BCL-XL. We also tested whether deficiency of BIM or PUMA, the two main pro-apoptotic antagonists of BCL-XL, could prevent reticulocyte death and anaemia caused by BCL-XL loss. Using an in vivo mouse model of tamoxifen-inducible Bclx gene deletion and in vitro assays with a BCL-XL-selective inhibitor, we interrogated each stage of erythrocyte differentiation for BCL-XL dependency. This revealed that reticulocytes, but not orthochromatic erythroblasts, require BCL-XL for their survival. Surprisingly, concurrent loss of BIM or PUMA had no significant impact on the development of anemia following acute BCL-XL deletion in vivo. However, analysis of mixed bone marrow chimaeric mice revealed that loss of PUMA, but not loss of BIM, partially alleviated impaired erythropoiesis caused by BCL-XL deficiency. Insight into how the network of pro-survival and pro-apoptotic proteins works will assist the development of strategies to mitigate the effects of abnormal cell death during erythropoiesis and prevent anaemia in patients treated with BCL-XL-specific BH3-mimetic drugs.
Publisher: Springer Nature
Research Division(s): Molecular Genetics Of Cancer; Cancer And Haematology; Cell Signalling And Cell Death; Chemical Biology
PubMed ID: 28682312
Publisher's Version: https://doi.org/10.1038/cddis.2017.304
NHMRC Grants: NHMRC/1016701, NHMRC/1016647, NHMRC/1020363, NHMRC/1058344,
Terms of Use/Rights Notice: Refer to copyright notice on published article.

Creation Date: 2017-07-26 12:48:10

Last Modified: 2017-07-26 02:52:16