Author Correction

There were four errors in both the online and the print versions of this paper. In the paragraph ‘Extracellular matrix synthesis is controlled by HIF-1 a under hypoxia ’ in Results on p. 1823, line 10, it should read ‘Significantly less extractable proteoglycans were detected in HIF-1a-null than in wild-type cultures after 44 hours exposure to 0.5 % oxygen (Fig. 5B)’. On p. 1824, the legend to Fig. 5, lane 3, should read ‘(A) Analysis of aggrecan gene expression: Bars represent-fold changes of aggrecan mRNA levels in HIF-1a-null cells compared with wild-type levels (normoxic and hypoxic wild-type expression taken as 1.0, respectively)’. On p. 1824, the legend to Fig. 6, lanes 12-13, should read ‘(normoxic and hypoxic wild-type expression taken as 1.0, respectively)’. On p. 1825, the legend to Fig. 7, lane 7 should read ‘(untreated normoxic and hypoxic expression taken as 1.0, respectively)’. We apologize for any inconvenience caused