Figure 1.

Generation of DP5-deficient mice. A, Schematic representation of the genomic dp5 locus (top), the gene-targeting construct (middle), and the targeted dp5 locus (bottom). DP5-null mice were generated by targeted disruption of dp5 through homologous recombination. The targeting vector (Tg Construct) was designed to replace the single coding exon of dp5 with a neomycin-resistant cassette. The probe used for Southern blot analysis is indicated. Nucleotide primers for PCR screening (arrowheads) are shown. S, SpeI; H, HindIII; N, NotI; B, BamHI; X, XbaI. B, Genomic tail DNA was digested with SpeI, and blots were hybridized with the probe indicated in A. Two mice of the indicated genotype are shown. C, Detection of normal and targeted alleles in genomic DNA by PCR analysis. D, Expression of dp5 transcripts in various tissues from DP5^+/+ and DP5^–/– mice by RT-PCR analysis. WT, Wild type; hsv-TK, herpes simplex virus-thymidine kinase; Bone M., bone marrow.