Figure 3.

HSI,II demonstrated minimal function following transient and stable transfections into pituitary and placental cell lines. (A) Transient transfection studies. The hGH-N promoter was fused to CAT with or without the linked HSI,II fragment (diagrammed below the histogram). The effect of HSI,II on CAT expression was determined after transfections into GH3, GHFT1, JEG3, and NIH 3T3 cells. The ordinate represents the ratio of the pHSI,II-hGH-CAT expression to phGHN-CAT. (B) Stable transfections and neo^r (neomycin-resistant) colony assay. The tk (thymidine kinase) promoter was linked to the neo^r gene in the presence or absence of HSI,II. The ordinate represents the ratio of neo^r colonies generated by pHSI,II-tk-neo^r to those generated with ptk-neo^r. (C) Stable transfections and neo^r colony assay in GHFT1 cells using the hGH gene promoter linked to the neo^r gene in the presence or absence of HSI,II. The ordinate represents the ratio of neo^r colonies generated by pHSI,II-hGHN-neo^r to those generated with phGHN-neo^r. Error bars span one standard deviation.