Dataset Information

Bcl11a Deficiency Leads to Hematopoietic Stem Cell Defects with an Aging-like Phenotype

ABSTRACT: B cell CLL/lymphoma 11A (BCL11A) is a transcription factor and regulator of hemoglobin switching that has emerged as a promising therapeutic target for sickle cell disease and thalassemia. In the hematopoietic system, BCL11A is required for B lymphopoiesis, yet its role in other hematopoietic cells, especially hematopoietic stem cells (HSCs) remains elusive. The extensive expression of BCL11A in hematopoiesis implicates context-dependent roles, highlighting the importance of fully characterizing its function as part of ongoing efforts for stem cell therapy and regenerative medicine. Here, we demonstrate that BCL11A is indispensable for normal HSC function. Bcl11a deficiency results in HSC defects, typically observed in the aging hematopoietic system. We find that downregulation of cyclin-dependent kinase 6 (Cdk6), and the ensuing cell-cycle delay, correlate with HSC dysfunction. Our studies define a mechanism for BCL11A in regulation of HSC function and have important implications for the design of therapeutic approaches to targeting BCL11A.

ORGANISM(S): Mus musculus

PROVIDER: GSE77207 | GEO | 2016/09/20

SECONDARY ACCESSION(S): PRJNA309701

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Basak A, Munschauer M, Lareau CA, Montbleau KE, Ulirsch JC, Hartigan CR, Schenone M, Lian J, Wang Y, Huang Y, Wu X, Gehrke L, Rice CM, An X, Christou HA, Mohandas N, Carr SA, Orkin SH, Chen JJ, Lander ES, and Sankaran VG. Increased production of the beta-like gamma-globin genes that form fetal hemoglobin can ameliorate the severity of sickle cell disease and beta-thalassemia, the major hemoglobin disorders. BCL11A is a key repressor of the gamma-globin genes and is expressed in a developmental stage-specific manner to regulate the physiologic fetal-to-adult hemoglobin switch. Despite extensive studies, the upstream mechanisms underlying the developmental expression of BCL11A and hemoglobin switching in humans have remained mysterious. Here we show that BCL11A is regulated at the level of mRNA translation during human hematopoietic development. While BCL11A mRNA is comparably expressed at all developmental stages in erythroid cells, robust protein expression only occurs in adult erythroid cells. Importantly, at the earlier stages of development, the observed reduction in protein expression is attributable to decreased synthesis and not increased degradation of BCL11A. While BCL11A protein is not well synthesized at these earlier stages of development, its mRNA curiously continues to be associated with ribosomes. Through unbiased proteomic analyses in erythroid cells, we demonstrate that the RNA-binding protein LIN28B, which is developmentally expressed in a reciprocal pattern to BCL11A, directly interacts with ribosomes. We show that the observed suppression of BCL11A protein translation is mediated by LIN28B through a direct interaction with BCL11A mRNA and independent of its role in let-7 microRNA biogenesis. Finally, we show that BCL11A is the major functional target in LIN28B-mediated fetal hemoglobin induction. Our results reveal a previously unappreciated regulatory mechanism underlying human hemoglobin switching and illuminate opportunities for developing improved treatments for sickle cell disease and beta-thalassemia.

Dataset Information

Bcl11a Deficiency Leads to Hematopoietic Stem Cell Defects with an Aging-like Phenotype

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure