Generation of p38βY323F mice. (A) A 5.1-kb genomic fragment of the mouse p38β locus (top) was cloned using SacI specific restriction sites and used to create the targeting vector (middle), into which a Y323F mutation and LoxP-flanked neomycin resistance gene were inserted. Insertion of the Y323F mutation deleted a BanII restriction site in the knockin allele. XmnI and HindIII specific sites used for Southern blot screening for the knockin allele. (B) Genotyping of p38βY323F mice was performed by Southern blot, yielding a 8.6-kb band that indicates the presence of WT allele (wt) and a 9.8-kb band representing the knockin (ki) allele. (C) Digestion of the WT p38β PCR product with BanII yielded a 274- and 101-bp band, and digestion of the p38βY323F mutant yielded an uncut 375-bp band lacking the BanII restriction site.
