Gene Expression Profiling during Erythroid Differentiation of K562 Cells

We studied the temporal changes in gene expression in K562 cells at intervals from 2 to 48 h following induction using differential display polymerase chain reaction and gene expression arrays. More than 110 cDNA fragments representing 86 unique mRNAs were either up- or downregulated during erythroid differentiation. Sixty-one of the differentially expressed cDNA fragments had more than 95% homology to known GenBank sequences; 21 represented cDNA sequences with only dbEST or high-throughput gene-screening database matches. Four fragments had no database matches. Using gene expression arrays, 73 differentially expressed genes were observed. Unique expressed sequence tags (ESTs) were used to “clone” two novel genes from available databases and their tissue expression was examined. Erythroid maturation in induced K562 cells is associated with differential expression of many genes. Some differentially expressed clones were transcription factors and 25 expressed fragments with open reading frames were found whose function remains unknown.