This sole substitution was sufficient to confer constitutive activity to the receptor variant ( PrlR ( I146L ) ) , as assessed in three reconstituted cell models ( Ba/F3 , HEK293 and MCF-7 cells ) by Prl-independent ( i ) PrlR tyrosine phosphorylation , ( ii ) activation of signal transducer and activator of transcription 5 ( STAT5 ) signaling , ( iii ) transcriptional activity toward a Prl-responsive reporter gene , and ( iv ) cell proliferation and protection from cell death .
O O O O O O O O O O O O O O B-GeneOrGeneProduct O B-SequenceVariant O O O O O O O O O O O B-CellLine O B-CellLine O B-CellLine O O O B-GeneOrGeneProduct O O O B-GeneOrGeneProduct O O O O O O O O B-GeneOrGeneProduct I-GeneOrGeneProduct I-GeneOrGeneProduct I-GeneOrGeneProduct I-GeneOrGeneProduct I-GeneOrGeneProduct I-GeneOrGeneProduct O B-GeneOrGeneProduct O O O O O O O O O O B-GeneOrGeneProduct O O O O O O O O O O O O O O O