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Fig. 1. Structure and expression of Lig 1 targeted alleles. The structure
of the 3' end of the wild-type and Lig 1 targeted alleles is
shown schematically. Lig 1 exons are depicted as numbered open boxes.
In the Lig 1-(#53) allele, exons 23-27 have been replaced
by the PGK-HPRT(RI) Hprt minigene. Hprt exons are shown as
numbered closed boxes with the Pgk promoter cross-hatched. In the
Lig 1-(#12) allele, exons 23-27 have been replaced by the
DWM110 Hprt minigene, with the Hprt promoter stippled. The
normal RNA splicing pattern for Lig 1 mRNA is indicated and the
sequences present in the Lig 1/Hprt fusion transcripts from the
Lig 1 targeted alleles are shown. Note that the fusion transcript
from the Lig 1-(#53) allele is rare.