Expression of two inward rectifier potassium channels is essential for differentiation of primitive human hematopoietic progenitor cells.
A potassium inward rectifier (K(ir)) current was previously shown by us to be induced in primitive hematopoietic progenitor cells, stimulated with the combination of interleukin-3 (IL-3) and stem cell factor (SCF). Biophysical features of whole cell currents implicated the involvement of more than one K(ir) channel type. Employing IL-3 + SCF stimulated human cord blood CD34+38- cells, we isolated and characterized different components of this current. Reverse transcription-polymerase chain reaction (RT-PCR) subcloning identified the expression of a strongly rectifying K(ir) channel (K(ir) 4.3) as well as a weakly rectifying K(ir) channel (K(ir) 1.1) in these cells. Inhibition of the expression of each of the channels suppressed progenitor cell generation by IL-3 and SCF-stimulated CD34+38- cells in 7-day suspension cultures. The variable expression of two essential inward rectifying potassium channels early in the course of hematopoietic progenitor cell differentiation may play a potentially important role in potassium homeostasis in these cells.
Bruce Rappaport Faculty of Medicine, Haifa, Israel.
O
O
Shirihai
B
B
Attali
D
D
Dagan
S
S
Merchav
D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D000595:Amino Acid Sequence; D015703:Antigens, CD; D018952:Antigens, CD34 / Q000032:analysis / Q000276:immunology; D000943:Antigens, Differentiation / Q000032:analysis; D001483:Base Sequence; D002454:Cell Differentiation; D003001:Cloning, Molecular; D016207:Cytokines / Q000037:antagonists & inhibitors; D005312:Fetal Blood; D006131:Growth Inhibitors / Q000235:genetics / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D006801:Humans; D015640:Ion Channel Gating; D007963:Leukocytes, Mononuclear; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D009244:NAD+ Nucleosidase / Q000032:analysis; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D015221:Potassium Channels / Q000096:biosynthesis* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D024661:Potassium Channels, Inwardly Rectifying; D012313:RNA / Q000378:metabolism
D015703:Antigens, CD; D018952:Antigens, CD34; D000943:Antigens, Differentiation; D016207:Cytokines; D006131:Growth Inhibitors; C086989:KCNJ1 protein, human; D008562:Membrane Glycoproteins; D016376:Oligonucleotides, Antisense; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D012313:RNA; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D009244:NAD+ Nucleosidase; D051997:ADP-ribosyl Cyclase 1