The alternative oxidase is used as a second terminal oxidase in the mitochondria, electrons are transfered directly from reduced ubiquinol to oxygen forming water [2]. This is not coupled to ATP synthesis and is not inhibited by cyanide, this pathway is a single step process [1]. In rice the transcript levels of the alternative oxidase are increased by low temperature [1].

1: Transcript levels of tandem-arranged alternative oxidase genes in rice are increased by low temperature. Ito Y, Saisho D, Nakazono M, Tsutsumi N, Hirai A; Gene 1997;203:121-129. PMID:9426242

2: Cloning and analysis of the alternative oxidase gene of Neurospora crassa. Li Q, Ritzel RG, McLean LL, McIntosh L, Ko T, Bertrand H, Nargang FE; Genetics 1996;142:129-140. PMID:8770590