- D. S. Finbloom, E. F. Petricoin, +12 authors 111-117 Eur
- Biochern. 209,1053-1061 J. 13,1350-1356
Growth hormone activates gene transcription of the serine protease inhibitors (SPI) 2.1 and 2.2 by an unknown mechanism. In order to define the promoter regions responsible for this effect and to characterize the transcription factors involved, we have performed gel electrophoresis mobility shift assays on nuclear extracts from cells lines transfected with growth hormone receptor cDNk We have identified a 9-base pair DNA element, the SPI-GLE 1, which forms a complex with nuclear proteins following activation by growth hormone and which, when placed upstream of a minimal thymidine kinase promoter, drives chloramphenicol acetyltransferase expression in a growth hormone-dependent fashion. This element is similar to those from several genes regulated by other cytokines including interferon. The growth hormone-induced complexes formed were dependent on tyrosine phosphorylation but did not contain the interferon-y-activated transcription factor Stat 91. Competition studies with oligonucleotides similar to the SPI-GLE 1 reveal the sequence of a consensus element that specifically binds growth hormone-regulated nuclear proteins.