Cloning and functional analysis of cdnas with entire open reading frame for 300 previously undefined genes expressed in CD34+ hematopoietic stem/progenitor cells

300 cDNAs containing putatively entire open reading frames (ORFs) for previously undefined genes were obtained from CD34+ hematopoietic stem/progenitor cells (HSPCs), based on EST cataloging, clone sequencing, in silica cloning and rapid amplification of cDNA ends (RACE). The cDNA sizes ranged from 360 to 3496 bp and their ORFs coded for peptides of 58 to 752 amino acids. Public database search indicated that 225 cDNAs exhibited sequence similarities to genes identified across a variety of species (bacteria, yeast, drosophila, arabidopsis and mammals not including primates). Homology analysis led to the recognition of 50 basic structure motifs/domains among these cDNAs. Genomic exon-intron organization could be established in 243 genes by integration of cDNA data with genome sequence information. Interestingly, a new gene named as HSPC070 on 3p was found to share a sequence of 105bp in 3' UTR with RAF gene in reversed transcription orientation. Chromosomal localizations were obtained using electronic mapping for 192 genes and with radiation hybrid (RH) for 38 ones. Macro-array technique was applied to screen the gene expression patterns in 5 hematopoietic cell lines (NB4, HL60, U937, K562 and Jurkat) and a number of genes with differential expression were found. The resource work has provided a wide range of information useful not only for expression genomics and annotation of genomic DNA sequence, but also for further research on the molecular regulation of hematopoietic development and differentiation. The biological functions of these previously undefined genes with regard to hematopoiesis are now under investigation.