Functional Requirements for a Samd14-Capping Protein Complex in Stress Erythropoiesis

ABSTRACT: Acute anemia induces rapid expansion of erythroid precursors and accelerated differentiation to replenish erythrocytes. Paracrine signals – involving cooperation between SCF/c-Kit signaling and other signaling inputs – are required for the activation and function of erythroid precursors in anemia. Our prior work revealed that the Sterile Alpha Motif (SAM) Domain 14 (Samd14) gene is transcriptionally upregulated in a model of acute anemia. Samd14 expression increases the regenerative capacity of the erythroid system and promotes stress-dependent c-Kit signaling. However, the mechanism underlying Samd14’s role in stress erythropoiesis is unknown. We identified a protein-protein interaction between Samd14 and the α- and β heterodimers of the F-actin capping protein (CP) complex. Knockdown of the CP β subunit increased erythroid maturation in ex vivo cultures and decreased colony forming potential of stress erythroid precursors. In a genetic complementation assay for Samd14 activity, our results revealed that the Samd14-CP interaction is a determinant of erythroid precursor cell levels and function. Samd14-CP promotes SCF/c-kit signaling in CD71med spleen erythroid precursors.

INSTRUMENT(S):

ORGANISM(S): Anemia Mus Musculus (mouse)

TISSUE(S): Cell Culture, Early Embryonic Cell

SUBMITTER: Sophe Alvarez  

LAB HEAD: Sophie Alvarez

PROVIDER: PXD030467 | Pride | 2022-08-09

REPOSITORIES: Pride