Translocation of transcription regulators into the nucleus during granulocyte commitment of HL-60 cells.
Expression of transcription factors required for lineage commitment of differentiating cells (C/EBPbeta and c-Myb) and for survival of differentiated cells (STATs and NFkappaB) was examined in the HL-60 cell line. Differentiation was induced by treating the cells with retinoic acid. c-Myb expression in the nucleus restored at the precommitment stage (18 h) what concurred with the highest nuclear level of C/EBPbeta, which suggests a combinatorial interaction of these transcription factors in the granulocytic signalling pathway. Expression of STAT5a and STAT5b varied during differentiation, whereas no significant changes were seen in STAT3 levels. Increased cytosolic level of NFkappaB p65 during precommitment and commitment stages of granulocytic differentiation coincided with augmentation of the STAT5a protein level, which could be evidence of their possible cooperation during granulocytic-lineage commitment of HL-60 cells. Our results suggest that the studied transcription factors cooperatively promote signalling in the differentiating promyelocytic HL-60 cell line in response to retinoic acid.
Department of Developmental Biology, Institute of Biochemistry, LT-2600 Vilnius, Lithuania. ruta.navakauskiene@bchi.lt
Ruta
R
Navakauskiene
Agné
A
Kulyte
Grazina
G
Treigyte
Arunas
A
Gineitis
Karl-Eric
KE
Magnusson
D002454:Cell Differentiation / Q000187:drug effects*; D002467:Cell Nucleus / Q000378:metabolism*; D006098:Granulocytes / Q000166:cytology / Q000378:metabolism*; D018922:HL-60 Cells; D006801:Humans; D007223:Infant; D021381:Protein Transport; D020598:Proto-Oncogene Proteins c-myb / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology; D014443:Tyrosine / Q000378:metabolism
D020598:Proto-Oncogene Proteins c-myb; D014157:Transcription Factors; D014443:Tyrosine; D014212:Tretinoin