Structural highlights
Function
[ETT1_SCHPO] Required for correct translation termination (By similarity). Positive regulator of the stability of the N-terminal transcription factor domain (Sre1N) of sre1 which is released from the membrane and enters the nucleus to activate hypoxic gene expression. Acts also as a direct inhibitor of ofd1. Functions probably by inhibiting the ability of the ofd1 to accelerate Sre1N degradation in absence of oxygen.[1] [2]
Publication Abstract from PubMed
Fission yeast protein Sre1, the homolog of the mammalian sterol regulatory element-binding protein (SREBP), is a hypoxic transcription factor required for sterol homeostasis and low-oxygen growth. Nro1 regulates the stability of the N-terminal transcription factor domain of Sre1 (Sre1N) by inhibiting the action of the prolyl 4-hydroxylase-like Ofd1 in an oxygen-dependent manner. The crystal structure of Nro1 determined at 2.2 A resolution shows an all-alpha-helical fold that can be divided into two domains: a small N-terminal domain, and a larger C-terminal HEAT-repeat domain. Follow-up studies showed that Nro1 defines a new class of nuclear import adaptor that functions both in Ofd1 nuclear localization and in the oxygen-dependent inhibition of Ofd1 to control the hypoxic response.
The hypoxic regulator of sterol synthesis nro1 is a nuclear import adaptor.,Yeh TL, Lee CY, Amzel LM, Espenshade PJ, Bianchet MA Structure. 2011 Apr 13;19(4):503-14. PMID:21481773[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Chen XQ, Du X, Liu J, Balasubramanian MK, Balasundaram D. Identification of genes encoding putative nucleoporins and transport factors in the fission yeast Schizosaccharomyces pombe: a deletion analysis. Yeast. 2004 Apr 30;21(6):495-509. PMID:15116432 doi:http://dx.doi.org/10.1002/yea.1115
- ↑ Lee CY, Stewart EV, Hughes BT, Espenshade PJ. Oxygen-dependent binding of Nro1 to the prolyl hydroxylase Ofd1 regulates SREBP degradation in yeast. EMBO J. 2009 Jan 21;28(2):135-43. doi: 10.1038/emboj.2008.271. PMID:19158663 doi:http://dx.doi.org/10.1038/emboj.2008.271
- ↑ Yeh TL, Lee CY, Amzel LM, Espenshade PJ, Bianchet MA. The hypoxic regulator of sterol synthesis nro1 is a nuclear import adaptor. Structure. 2011 Apr 13;19(4):503-14. PMID:21481773 doi:10.1016/j.str.2011.01.017