The binding of PTB to the HIF-1α IRES is enhanced in hypoxic conditions

<p><b>Copyright information:</b></p><p>Taken from "The polypyrimidine tract-binding protein stimulates HIF-1α IRES-mediated translation during hypoxia"</p><p>Nucleic Acids Research 2005;33(21):6884-6894.</p><p>Published online 7 Dec 2005</p><p>PMCID:PMC1310900.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> () Western blot analysis using an anti-HIF-1α antibody (upper panel), and an anti-β-actin antibody as loading control (lower panel) on blots containing total cell extracts derived from HEK293T cells grown in either 20% oxygen (0 h) or 1% oxygen for 8 or 16 h. () Biotinylated HIF-1α IRES RNA-bound to streptavidin beads was incubated with cytoplasmic extracts derived from the HEK293T cells described in (A). After extensive washing, RNA-bound proteins were analyzed by western blotting using an anti-PTB antibody (upper panel). Western blot analysis of the cytoplasmic cell extracts used for RNA affinity chromatography using an anti-PTB antibody (second panel), an anti-β-actin antibody as loading control (third panel) and an anti-poly(ADP-ribose)polymerase antibody, showed equal cytoplasmic PTB expression in all samples. As positive control for poly(ADP-ribose)polymerase expression whole cell extract from normal HEK293T cells (indicated by asterisk) was used

The HIF-1α IRES efficiently mediates translation during hypoxic conditions

<p><b>Copyright information:</b></p><p>Taken from "The polypyrimidine tract-binding protein stimulates HIF-1α IRES-mediated translation during hypoxia"</p><p>Nucleic Acids Research 2005;33(21):6884-6894.</p><p>Published online 7 Dec 2005</p><p>PMCID:PMC1310900.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> Influence of oxygen depletion on HIF-1α and PITSLRE IRES activity. HEK293T cells were transfected with the bicistronic vectors Di-HIF and Di-PITSLRE (), or with a combination of the monocistronic reporter plasmids pSV-Fluc + pSV-HIF-Rluc and pSV-Fluc + pSV-Rluc (). Transfectants were then kept in either 20 or 1% oxygen for 24 h. The bars represent the averages ( = 3) ± SD of Firefly luciferase (Fluc) and luciferase (Rluc) activities in normoxic (open bars) or hypoxic (closed bars) conditions. Bars are representative of three independent transfection experiments