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Fig. 1. Characterization of XRnf12. (A) Amino acid sequence alignment of XRnf12,
XRnf12B, and XRnf12C, as well as mouse and chick Rnf12. Note the repetitive
heptamers present in XRnf12B and XRnf12C. A PDZ domain-binding motif is
present in the C terminus. NLS, nuclear localization signal; asterisks, sites
of mutation in the RING mutant XRnf12(HC>AA). DDBJ Accession Numbers are:
XRnf12 (AB114039), XRnf12B (AB114040) and XRnf12C (AB114041). (B) Schematic
representation of mRnf12, XRnf12, XRnf12B, and XRnf12C. (C) The N-terminal
region (aa 1-283) of XRnf12 interacts with LIM homeodomain proteins and Ldb1.
GST pull-down assay was performed with 35S-labeled Xlim-1, Xlim-3,
Xlim-5, Ldb1 and Ldb1
C. While GST XRnf12
C interacts with all of
the proteins tested, GST XRnf12
N shows little interaction. GST and GST
Ldb1 serves as negative and positive controls, respectively.