@entity24778 ( @entity24778 ) is the major regulator of granulopoiesis and acts through binding to its specific receptor ( @entity24079 ) on neutrophilic granulocytes. Previous studies of signaling from the 4 @entity24079 cytoplasmic @entity669 residues used model cell lines that may have idiosyncratic, nonphysiological responses. This study aimed to identify specific signals transmitted by the receptor @entity669 residues in primary myeloid cells. To bypass the presence of endogenous @entity24079 , a chimeric receptor containing the extracellular domain of the @entity12841 in place of the entire extracellular domain of the @entity24079 was used. A series of chimeric receptors containing @entity669 mutations to @entity815 , either individually or collectively, was constructed and expressed in primary bone marrow cells from @entity24778 -deficient @entity19 . Proliferation and differentiation responses of receptor-expressing bone marrow cells stimulated by epidermal growth factor were measured. An increased 50% effective concentration to stimulus of the receptor Y(null) mutant indicated that specific signals from @entity669 residues were required for cell proliferation, particularly at low concentrations of stimulus. Impaired responses by mutant receptors implicated @entity24079 Y(764) in cell proliferation and Y(729) in granulocyte differentiation signaling. In addition, different sensitivities to ligand stimulation between mutant receptors indicated that @entity24079 Y(744) and possibly Y(729) have an inhibitory role in cell proliferation. STAT activation was not affected by @entity669 mutations, whereas @entity13436 activation appeared to depend, at least in part, on Y(764). These observations have suggested novel roles for the @entity24079 @entity669 residues in primary cells that were not observed previously in studies in cell lines.

@entity669 residues of the XXXX receptor transmit proliferation and differentiation signals in @entity19 bone marrow cells.

@entity12841 :: ('13649(Tax:10090)', 'Gene') :: ['epidermal growth factor receptor'] @entity19 :: ('10090', 'Species') :: ['mice'] @entity24778 :: ('12985(Tax:10090)', 'Gene') :: ['G-CSF', 'Granulocyte colony-stimulating factor'] @entity13436 :: ('26413(Tax:10090)', 'Gene') :: ['ERK'] @entity24079 :: ('12986(Tax:10090)', 'Gene') :: ['G-CSF-R'] @entity815 :: ('CHEBI:28044', 'Chemical') :: ['phenylalanine'] @entity669 :: ('CHEBI:18186', 'Chemical') :: ['tyrosine']
@entity24778 :: (12985(Tax:10090),Gene) :: ['granulocyte colony-stimulating factor']
