Intracellular redistribution of nuclear and nucleolar proteins during differentiation of 32D murine hemopoietic cells.
We have investigated the intracellular localization of four proteins in murine hemopoietic 32D and 32D-derived cells during exponential growth and after induction of differentiation. The four proteins studied were the insulin receptor substrate-1 (IRS-1), the ID2 protein, nucleolin, and the upstream binding factor (UBF), all of which are involved directly or indirectly in the differentiation program. These four proteins were found to be predominantly nuclear (and/or nucleolar) during exponential growth, as expected. In three models of induced differentiation along the granulocytic pathway, IRS-1, ID2, and nucleolin shifted in part to the cytoplasm, where their levels eventually decreased. UBF also disappeared during differentiation, but we could not detect a cytoplasmic shift in this protein. These experiments indicate that induction of granulocytic differentiation in 32D and 32D-derived cells is accompanied by intracellular redistribution of proteins. This nucleo-cytoplasmic shuttle may play a significant role in the changes in gene expression that occur during differentiation.
Tu
Xiao
X
Kimmel Cancer Center, Thomas Jefferson University, 233 S. 10th Street, Philadelphia, PA 19107, USA.
Baffa
Raffaele
R
Luke
Stephen
S
Prisco
Marco
M
Baserga
Renato
R
D021581:Active Transport, Cell Nucleus; D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D051797:Inhibitor of Differentiation Protein 2; D055504:Insulin Receptor Substrate Proteins; D051379:Mice; D009687:Nuclear Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism; D035463:Pol1 Transcription Initiation Complex Proteins / Q000378:metabolism; D021381:Protein Transport; D016601:RNA-Binding Proteins / Q000378:metabolism; D012097:Repressor Proteins; D014157:Transcription Factors / Q000378:metabolism; D000097796:Nucleolin
D004268:DNA-Binding Proteins; D051797:Inhibitor of Differentiation Protein 2; D055504:Insulin Receptor Substrate Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D035463:Pol1 Transcription Initiation Complex Proteins; D016601:RNA-Binding Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D000097796:Nucleolin; C497452:Idb2 protein, mouse; C526295:Irs1 protein, mouse; C063844:transcription factor UBF