Generation and molecular characterization of the flt3L mutation.

(A) Schematic diagram of the wild-type flt3L gene and flt3L targeting vector. Exons are depicted in filled boxes. Relevant restriction sites, as well as the probe used for genomic Southern analysis, are shown. The positions of the initiator methionine (ATG) and transmembrane (TM) domain are depicted. (B) Genomic DNA from flt3L-targeted embryonic stem cells as well as representative +/+, +/−, and −/− mice were digested with XbaI and subject to Southern blot analysis using the depicted probe. (C) First strand cDNAs derived from either bone marrow (B) or spleen (S) of +/+ and −/− adult mice and a genomic DNA control (G) were amplified using flt3L specific primers and subjected to Southern blot analysis using a flt3L cDNA probe. Duplicate samples were amplified using mouse β-actin specific primers and visualized by ethidium bromide staining.