Cell surface receptor for IL3 expressed on hematopoietic progenitor cells, monocytes and B-lymphocytes that controls the production and differentiation of hematopoietic progenitor cells into lineage-restricted cells (PubMed:10527461). Ligand stimulation rapidly induces hetrodimerization with IL3RB, phosphorylation and enzyme activity of effector proteins such as JAK2 and PI3K that play a role in signaling cell proliferation and differentiation. Activation of JAK2 leads to STAT5-mediated transcriptional program (By similarity). Interacts with IL3 (PubMed:29374162). Heterodimer of an alpha and a beta subunit. The beta subunit is common to the IL3, IL5 and GM-CSF receptors. The WSXWS motif appears to be necessary for proper protein folding and thereby efficient intracellular transport and cell-surface receptor binding. The box 1 motif is required for JAK interaction and/or activation. The gene coding for this protein is located in the pseudoautosomal region 1 (PAR1) of X and Y chromosomes. Belongs to the type I cytokine receptor family. Type 5 subfamily.