(A) Cellular O2
uptake rates in wild-type and ρ0-Hep3B cells.
(B) Southern blot analysis of undigested total cellular DNA
from wild-type and ρ0-Hep3B cells. Hybridization was
performed with a cytochrome oxidase subunit II probe, spanning bps
7757–8195, generated by reverse transcription–PCR. (C) EPO
secretion from wild-type (wt) and ρ0-Hep3B cells exposed
to normoxia (21% O2/5% CO2/74%
N2), hypoxia (1.5% O2/5%
CO2/93.5% N2), or CoCl2 (100
μM) during normoxia for 24 hr (n = 3, mean
± SD). EPO was measured by radioimmunoassay (46). (D)
Northern blot analysis of RNA from wild-type and ρ0-Hep3B
cells during normoxia (21% O2/5% CO2/74%
N2), hypoxia (1.5% O2/5%
CO2/93.5% N2), or CoCl2 (100
μM) during normoxia for 24 hr. ALDA, aldolase; PGK-1,
phosphoglycerate kinase. (E) HIF-1 DNA binding in nuclear
extracts from wild-type and ρ0-Hep3B cells. Both cell
types were exposed to normoxia (21% O2/5%
CO2/74% N2), hypoxia (1.5%
O2/5% CO2/93.5% N2) or
CoCl2 (100 μM) during normoxia for 4 hr. C, constitutive;
NS, nonspecific.