Role of a truncated erythropoietin receptor for erythroid differentiation.
Erythropoietin (EPO) is a cytokine that regulates erythropoiesis through the EPO receptor (EPOR). We reported previously that erythroid progenitor cells express both a full-length and a truncated form of EPOR (EPOR-F and EPOR-Tph). EPOR-Tph cannot transmit growth signals and acts as a dominant negative regulator against EPOR-F-mediated signals for cell survival and growth. Upon transfection of EPOR-F in a cell line, Ba/F3, beta-globin accumulation, which is considered to be a marker of erythroid-differentiation, is inducible in the transformants. We show here that the co-expression of EPOR-Tph in EPOR-F-transformants does not inhibit and rather upregulates the beta-globin induction while inhibiting survival and growth of the transformants. These data suggest that, in contrast to survival and growth signals, EPOR-Tph acts as a positive regulator for erythroid-differentiation signals in erythroid progenitor cells.
Nakamura
Y
Y
Institute of Basic Medical Sciences, University of Tsukuba, Ibaraki, Japan.
Tokumoto
Y
Y
Nakauchi
H
H
D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division; D002460:Cell Line; D002470:Cell Survival; D017931:DNA Primers; D004921:Erythropoietin / Q000494:pharmacology*; D005914:Globins / Q000096:biosynthesis; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D007700:Kinetics; D051379:Mice; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D017467:Receptors, Erythropoietin / Q000096:biosynthesis* / Q000502:physiology; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection
D017931:DNA Primers; D012333:RNA, Messenger; D017467:Receptors, Erythropoietin; D011994:Recombinant Proteins; D004921:Erythropoietin; D005914:Globins