FIG. 1.

Gene targeting of nsmase 1. (A) Strategy for the targeted disruption of the gene locus. The wild-type allele, the targeting vector, the recombined gene locus, and a schematic view of the occurring restriction fragment length polymorphism and the probes and primers used are shown. (B) Southern blot analysis of EcoRI-XbaI-digested ES cell DNA. The blot was probed with the 3′ probe and the neo probe, showing the fragments indicated in panel A. wt, wild type. (C) PCR analysis of ES cell DNA with primers specific for the wild-type allele (H) and the targeted allele (N). (D) Analysis of mouse tail DNA showing the expected restriction fragments and PCR fragments for each genotype. X, XbaI; E, EcoRI, B, BamHI; Sma, SmaI; K, KpnI; H, HindIII; and P, PstI.