Fig. 1. Hypomorphic phenotypes in BAC transgene-rescued Lim1 mutants. (A) Schematic diagram of mouse BAC clones around the Lim1 locus. (Adapted, with permission, from Celera Discovery System.) (B) Breeding scheme to generate BAC transgene-rescued Lim1 mutants. (C) PCR genotyping of neonates. Because two different null alleles of Lim1 (Lim1^neo and Lim1^lz) were used, BAC transgene-rescued Lim1 mutants were easily identified by PCR genotyping. (D-Q) Phenotypes of Lim1-null (D,H), BAC transgene-rescued Lim1 mutants for line 5 (E,I,L,O) and line 7 (F,J,M,P), and wild-type (G,K,N,Q) mice at birth. (D-G) Lateral view of the head region. Insets in D and E show frontal views. Arrowheads indicate ears. (H-K) Ventral view of urogenital system of female neonates. Arrowheads indicate connective tissues that lack the uterus, which is removed and not shown in H. (L-N) Hematoxylin and Eosin-stained metanephros. (O-Q) High magnification of the cortical region of the metanephros in L-N, respectively. (R-Y) Whole-mount in situ hybridization with a Lim1 probe at E12.5 of the metanephros (R-U) and urogenital ridges (V-Y) from BAC transgene-rescued Lim1 mutants (Line 7) (R,S,V,W) and wild-type (T,U,X,Y). (S,U,W,Y) High-magnification images in R, T, V and X. a, adrenal; cd, collecting duct; cm, condensed mesenchyme; g, gonad; ge, genitalia; gl, glomerulus; k, kidney; md, Müllerian duct; np, nephron progenitor; ov, ovary; tu, tubules of nephron; ub, ureteric bud; ur, ureter; ut, uterus.