CLONING AND SEQUENCING OF AN ALTERNATIVE SPLICING-DERIVED CDNA VARIANT OF THE GM-CSF RECEPTOR-ALPHA SUBUNIT, WHICH ENCODES A TRUNCATED PROTEIN

GM-CSF interacts with the low affinity GM-CSF receptor alpha-subunit, which leads to high affinity association with the alpha-subunit/common beta-subunit complex and transduction of intracellular signals leadin g to proliferation, differentiation, and/or activation of hemopoietic cells, predominantly in the neutrophil and monocyte/macrophage lineage s. Several alternative splicing-derived variants of the GM-CSF recepto r alpha-subunit have been described previously by this and other labor atories. A newly discovered alternative-splicing derived variant was i solated from the peripheral blood mononuclear cells of a patient with juvenile myelomonocytic leukemia. This variant lacks 397 base pairs co rresponding to exons 8-11 of the wild type GM-CSF receptor alpha-subun it cDNA and potentially encodes a 233 amino acid protein lacking a mem brane-anchoring domain and creating the fourth known potential soluble isoform of the alpha-subunit of the GM-CSF receptor. (C) 1998 Wiley-L iss, Inc.