title: Regulation of urokinase receptor expression by phosphoglycerate kinase.
abstract: Post-transcriptional regulation represents a major mechanism by which eukaryotic gene expression is regulated through cis-trans interactions that serve as signals for rapid alterations of messenger RNA (mRNA) stability. Regulation of urokinase-type plasminogen activator receptor (uPAR) mRNA involves the interaction of a uPAR mRNA coding region sequence with a 50 kD uPAR mRNA binding protein. We purified this protein from human bronchial epithelial (Beas2B) cells and identified it as phosphoglycerate kinase (PGK). We cloned PGK cDNA by polymerase chain reaction and expressed the recombinant PGK protein, which specifically bound the uPAR mRNA coding region by gel mobility shift and Northwestern blotting. We also confirmed a direct interaction of PGK protein with uPAR mRNA by immunoprecipitation. Overexpression of PGK in uPAR-overproducing H157 lung carcinoma cells resulted in decreased cytoplasmic uPAR mRNA and cell surface uPAR protein expression. Reduced uPAR mRNA expression involved decreased stability of the uPAR mRNA. Decline in 3H-thymidine incorporation and migration occurred in H157 cells transfected with PGK cDNA. These results demonstrate that PGK regulates uPAR expression at the post-transcriptional level.
authors.affiliation: Department of Specialty Care Services, The University of Texas Health Center at Tyler, Tyler, TX 75708, USA. sreerama.shetty@uthct.edu
authors.forename: Sreerama
authors.initials: S
authors.lastname: Shetty
authors.forename: Harish
authors.initials: H
authors.lastname: Muniyappa
authors.forename: Prathap K S
authors.initials: PK
authors.lastname: Halady
authors.forename: Steven
authors.initials: S
authors.lastname: Idell
mesh_terms: D001980:Bronchi / Q000201:enzymology*; D002460:Cell Line; D018076:DNA, Complementary / Q000032:analysis / Q000235:genetics; D015536:Down-Regulation / Q000235:genetics; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D016366:Open Reading Frames / Q000235:genetics; D010735:Phosphoglycerate Kinase / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D011485:Protein Binding / Q000235:genetics; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics; D020871:RNA Stability / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism; D055293:Receptors, Urokinase Plasminogen Activator; D020545:Respiratory Mucosa / Q000201:enzymology*; D014407:Tumor Cells, Cultured
chemical_list: D018076:DNA, Complementary; C524898:PLAUR protein, human; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D055293:Receptors, Urokinase Plasminogen Activator; D010735:Phosphoglycerate Kinase