This report summarizes new evidence for a plasma-membrane-associated hydroquinone oxidase designated as CNOX (constitutive plasma membrane NADH oxidase) that functions as a terminal oxidase for a plasma membrane oxidoreductase (PMOR) electron transport chain to link the accumulation of lesions in mitochondrial DNA to cell-surface accumulations of reactive oxygen species. Previous considerations of plasma membrane redox changes during aging have lacked evidence for a specific terminal oxidase to catalyze a flow of electrons from cytosolic NADH to molecular oxygen (or to protein disulfides). Cells with functionally deficient mitochondria become characterized by an anaerobic metabolism. As a result, NADH accumulates from the glycolytic production of ATP. Elevated PMOR activity has been shown to be necessary to maintain the NAD(+)/NADH homeostasis essential for survival. Our findings demonstrate that the hyperactivity of the PMOR system results in an NADH oxidase (NOX) activity capable of generating reactive oxygen species at the cell surface. This would serve to propagate the aging cascade both to adjacent cells and to circulating blood components. The generation of superoxide by NOX forms associated with aging is inhibited by coenzyme Q and provides a rational basis for the anti-aging activity of circulating coenzyme Q.
Surface oxidase and oxidative stress propagation in aging
D.M. Morre, G. Lenaz, D.J. Morre; Surface oxidase and oxidative stress propagation in aging. J Exp Biol 15 May 2000; 203 (10): 1513–1521. doi: https://doi.org/10.1242/jeb.203.10.1513
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The Forest of Biologists
We are excited to announce the launch of The Forest of Biologists, a new biodiversity initiative created with support from the Woodland Trust, aiming to counteract nature loss and safeguard some of the most critically endangered ecosystems for future generations. Do take a look around our virtual forest. For every Research Article and Review/Commentary article that is published in JEB, a native tree is planted in a forest in the UK.
Celebrating 100 years of discovery
We are proud to be celebrating 100 years of discovery in Journal of Experimental Biology. Visit our centenary webpage to find out more about how we are marking this historic milestone.
Looking back on the first issue of JEB
Journal of Experimental Biology launched in 1923 as The British Journal of Experimental Biology. As we celebrate our centenary, we look back at that first issue and the zoologists publishing their work in the new journal.
In our new Conversation series JEB@100, JEB Editor-in-Chief Craig Franklin talks about the big outstanding questions in the field of physiological plasticity and why he thinks a sense of community is key to the journal's success. Find out more here.
Deer mice overheat and struggle to run in high temperatures
The impacts of warming temperatures associated with climate change on performance are poorly understood in most mammals. Matthew Eizenga and colleagues show that deer mice run comfortably at 25C, but as the temperature rises the tiny rodents start to struggle and they begin overheating at air temperatures of 38C, which could be a big problem for the animals in future climate scenarios.
Propose new workshop for 2025
Do you have an idea for a Workshop? We are now accepting proposals for our 2025 Biologists Workshops programme. As the scientific organiser, your involvement will be focused on the science. We'll take care of all the logistics. In 2025 we'll continue our efforts to diversify our Workshop programme and will be reserving one of our Workshops for an application from a Global South (GS) country to host an event overseas.