Abstract
Hypoxia-inducible factor (HIF) is a transcription factor that regulates fundamental cellular processes in response to changes in oxygen concentration. HIFα protein levels are increased in most solid tumours and correlate with patient prognosis. The link between HIF and apoptosis, a major determinant of cancer progression and treatment outcome, is poorly understood. Here we show that Caenorhabditis elegans HIF-1 protects against DNA-damage-induced germ cell apoptosis by antagonizing the function of CEP-1, the homologue of the tumour suppressor p53. The antiapoptotic property of HIF-1 is mediated by means of transcriptional upregulation of the tyrosinase family member TYR-2 in the ASJ sensory neurons. TYR-2 is secreted by ASJ sensory neurons to antagonize CEP-1-dependent germline apoptosis. Knock down of the TYR-2 homologue TRP2 (also called DCT) in human melanoma cells similarly increases apoptosis, indicating an evolutionarily conserved function. Our findings identify a novel link between hypoxia and programmed cell death, and provide a paradigm for HIF-1 dictating apoptotic cell fate at a distance.
첫댓글 포도당이 극도로 감소된 상태에서 아세틸 CoA는미토콘드리아의 TCA회로에 들어가지 못함. 옥살로아세테이트가 포도당에서 만들어지기 때문임. 즉 포도당이 없는 환경에서는 지방산이 유래한 아세틸 CoA를 에너지로 변환하기 위한 옥살로아세테이트가 부족하여 미토콘드리아의 TCA회로가 잘 작용하지 않음
왜 케토제닉일때와 일반식일때 지방대사의 차이가 나는지 궁금했었는데
정답을 찾았습니다. 감사합니다 교수님
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