Epo-Induced Erythroid Maturation Is Dependent on Plcγ1 Signaling

ABSTRACT: Erythropoiesis is a tightly regulated process. Development of red blood cells occurs through differentiation of hematopoietic stem cells into more committed progenitors and finally into erythrocytes. Binding of erythropoietin to its receptor (EpoR) is strictly required for erythropoiesis as it promotes survival and late maturation of erythroid progenitors. In vivo and in vitro studies have highlighted the requirement of EpoR signaling through Jak2 tyrosine-kinase and Stat5a/b as a central pathway. Here, we demonstrate that phospholipase C gamma 1 (Plcγ1) is activated downstream of EpoR/Jak2 independently of Stat5. Plcγ1-deficient proerythroblasts and erythroid progenitors exhibited strong impairment in differentiation and colony-forming potential. In vivo, suppression of Plcγ1 in immunophenotypically defined hematopoietic stem cells (Lin-Sca1+KIT+CD48-CD150+) severely reduced erythroid development. To identify Plcγ1 effector molecules involved in regulation of erythroid differentiation we assessed for changes on the level of transcription and DNA methylation after inactivation of Plcγ1. The single common downstream effector was H2AFY2, which encodes for the histone variant macroH2A2 (mH2A2). Suppression of macroH2A2 expression recapitulated the effects of Plcγ1 knockdown on erythroid maturation. Taken together, our findings identify Plcγ1 and its downstream target macroH2A2, as a “non-canonical” signaling pathway essential for erythroid differentiation. MCIP-seq was used to interrogate methylation changes during Epo-induced differentiation of murine I/11 erythroblastic cell line upon knock-down of Plcy1 as compared to a mock control. Two different shRNA constructs that target Plcg1 were investigated at two different time points.

ORGANISM(S): Mus musculus

SUBMITTER: Daniel Lipka 

PROVIDER: E-GEOD-60087 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress