TY - JOUR
T1 - Identification of the Hypoxia-Inducible Factor 1α-Responsive HGTD-P Gene as a Mediator in the Mitochondrial Apoptotic Pathway
AU - Lee, Mi Jung
AU - Kim, Jee Youn
AU - Suk, Kyoungho
AU - Park, Jae Hoon
PY - 2004/5
Y1 - 2004/5
N2 - Hypoxia-inducible factor 1α (HIF-1α) controls the cellular responses to hypoxia, activating transcription of a range of genes involved in adaptive processes such as increasing glycolysis and promoting angiogenesis. However, paradoxically, HIF-1α also participates in hypoxic cell death. Several gene products, such as BNip3, RTP801, and Noxa, were identified as HIF-1α-responsive proapoptotic proteins, but the complicated hypoxic cell death pathways could not be completely explained by the few known genes. Moreover, molecules linking the proapoptotic signals of HIF-1α directly to mitochondrial permeability transition are missing. In this work, we report the identification of an HIF-1α-responsive proapoptotic molecule, HGTD-P. Its expression was directly regulated by HIF-1α. through a hypoxia-responsive element on the HGTD-P promoter region. When overexpressed, HGTD-P was localized to mitochondria and facilitated apoptotic cell death via typical mitochondrial apoptotic cascades, including permeability transition, cytochrome c release, and caspase 9 activation. In the process of permeability transition induction, the death-inducing domain of HGTD-P physically interacted with the voltage-dependent anion channel. In addition, suppression of HGTD-P expression by small interfering RNA or antisense oligonucleotides protected against hypoxic cell death. Taken together, our data indicate that HGTD-P is a new HIF-1α-responsive proapoptotic molecule that activates mitochondrial apoptotic cascades.
AB - Hypoxia-inducible factor 1α (HIF-1α) controls the cellular responses to hypoxia, activating transcription of a range of genes involved in adaptive processes such as increasing glycolysis and promoting angiogenesis. However, paradoxically, HIF-1α also participates in hypoxic cell death. Several gene products, such as BNip3, RTP801, and Noxa, were identified as HIF-1α-responsive proapoptotic proteins, but the complicated hypoxic cell death pathways could not be completely explained by the few known genes. Moreover, molecules linking the proapoptotic signals of HIF-1α directly to mitochondrial permeability transition are missing. In this work, we report the identification of an HIF-1α-responsive proapoptotic molecule, HGTD-P. Its expression was directly regulated by HIF-1α. through a hypoxia-responsive element on the HGTD-P promoter region. When overexpressed, HGTD-P was localized to mitochondria and facilitated apoptotic cell death via typical mitochondrial apoptotic cascades, including permeability transition, cytochrome c release, and caspase 9 activation. In the process of permeability transition induction, the death-inducing domain of HGTD-P physically interacted with the voltage-dependent anion channel. In addition, suppression of HGTD-P expression by small interfering RNA or antisense oligonucleotides protected against hypoxic cell death. Taken together, our data indicate that HGTD-P is a new HIF-1α-responsive proapoptotic molecule that activates mitochondrial apoptotic cascades.
UR - http://www.scopus.com/inward/record.url?scp=1942453828&partnerID=8YFLogxK
U2 - 10.1128/MCB.24.9.3918-3927.2004
DO - 10.1128/MCB.24.9.3918-3927.2004
M3 - Article
C2 - 15082785
AN - SCOPUS:1942453828
SN - 0270-7306
VL - 24
SP - 3918
EP - 3927
JO - Molecular and Cellular Biology
JF - Molecular and Cellular Biology
IS - 9
ER -