| Specifically , it was shown that an amino terminal segment of BP 180 ( aa . 13 25 ) contains the information necessary for binding to p120ctn isoforms 1 3 , but not to the isoform 4 , suggesting that the interacting domain is located immediately upstream from the Armadillo repeats and is encoded by exons 5 and 6 , which are subject to alternative splicing only in a minority of transcripts . ^^^ Finally , the tissue specific expression of BP 180 was shown to partially overlap with that of p120ctn , suggesting that the interaction of these two proteins may contribute to the modulation of cell cell / matrix interactions in such tissues . . ^^^ |