The action mechanisms revealed by the biochemical and structural analyses of replicative and translesion synthesis (TLS) DNA polymerases (Pols) are retained in their cellular roles. In this regard, DNA polymerase θ differs from other Pols in that whereas purified Polθ misincorporates an A opposite 1,N6-ethenodeoxyadenosine (ϵdA) using an abasic-like mode, Polθ performs predominantly error-free TLS in human cells. To test the hypothesis that Polθ adopts a different mechanism for replicating through ϵdA in human cells than in the purified Pol, here we analyze the effects of mutations in the two highly conserved tyrosine residues, Tyr-2387 and Tyr-2391, in the Polθ active site. Our findings that these residues are indispensable for TLS by the purified Pol but are not required in human cells, as well as other findings, provide strong evidence that the Polθ active site is reconfigured in human cells to stabilize ϵdA in the syn conformation for Hoogsteen base pairing with the correct nucleotide. The evidence that a DNA polymerase can configure its active site entirely differently in human cells than in the purified Pol establishes a new paradigm for DNA polymerase function.

We previously reported that overexpression of cytochrome P450 family 24 subfamily A member 1 (CYP24A1) increases lung cancer cell proliferation by activating RAS signaling and that CYP24A1 knockdown inhibits tumor growth. However, the mechanism of CYP24A1-mediated cancer cell proliferation remains unclear. Here, we conducted cell synchronization and biochemical experiments in lung adenocarcinoma cells, revealing a link between CYP24A1 and anaphase-promoting complex (APC), a key cell cycle regulator. We demonstrate that CYP24A1 expression is cell cycle–dependent; it was higher in the G2-M phase and diminished upon G1 entry. CYP24A1 has a functional destruction box (D-box) motif that allows binding with two APC adaptors, CDC20-homologue 1 (CDH1) and cell division cycle 20 (CDC20). Unlike other APC substrates, however, CYP24A1 acted as a pseudo-substrate, inhibiting CDH1 activity and promoting mitotic progression. Conversely, overexpression of a CYP24A1 D-box mutant compromised CDH1 binding, allowing CDH1 hyperactivation, thereby hastening degradation of its substrates cyclin B1 and CDC20, and accumulation of the CDC20 substrate p21, prolonging mitotic exit. These activities also occurred with a CYP24A1 isoform 2 lacking the catalytic cysteine (Cys-462), suggesting that CYP24A1's oncogenic potential is independent of its catalytic activity. CYP24A1 degradation reduced clonogenic survival of mutant KRAS-driven lung cancer cells, and calcitriol treatment increased CYP24A1 levels and tumor burden in Lsl-KRASG12D mice. These results disclose a catalytic activity-independent growth-promoting role of CYP24A1 in mutant KRAS-driven lung cancer. This suggests that CYP24A1 could be therapeutically targeted in lung cancers in which its expression is high.

Nucleoside analogues are a valuable experimental tool. Incorporation of these molecules into newly synthesized DNA (i.e. pulse-labeling) is used to monitor cell proliferation or to isolate nascent DNA. Some of the most common nucleoside analogues used for pulse-labeling of DNA in cells are the deoxypyrimidine analogues 5-ethynyl-2'-deoxyuridine (EdU) and 5-ethynyl-2'-deoxycytidine (EdC). Click chemistry enables conjugation of an azide molecule tagged with a fluorescent dye or biotin to the alkyne of the analog, which can then be used to detect incorporation of EdU and EdC into DNA. The use of EdC is often recommended because of the potential cytotoxicity associated with EdU during longer incubations. Here, by comparing the relative incorporation efficiencies of EdU and EdC during short 30-min pulses, we demonstrate significantly lower incorporation of EdC than of EdU in noninfected human fibroblast cells or in cells infected with either human cytomegalovirus or Kaposi's sarcoma-associated herpesvirus. Interestingly, cells infected with herpes simplex virus type-1 (HSV-1) incorporated EdC and EdU at similar levels during short pulses. Of note, exogenous expression of HSV-1 thymidine kinase increased the incorporation efficiency of EdC. These results highlight the limitations when using substituted pyrimidine analogues in pulse-labeling and suggest that EdU is the preferable nucleoside analogue for short pulse-labeling experiments, resulting in increased recovery and sensitivity for downstream applications. This is an important discovery that may help to better characterize the biochemical properties of different nucleoside analogues with a given kinase, ultimately leading to significant differences in labeling efficiency of nascent DNA.

Tau is a microtubule-associated protein that plays a major role in Alzheimer's disease (AD) and other tauopathies. Recent reports indicate that, in the presence of crowding agents, tau can undergo liquid–liquid phase separation (LLPS), forming highly dynamic liquid droplets. Here, using recombinantly expressed proteins, turbidimetry, fluorescence microscopy imaging, and fluorescence recovery after photobleaching (FRAP) assays, we show that the divalent transition metal zinc strongly promotes this process, shifting the equilibrium phase boundary to lower protein or crowding agent concentrations. We observed no tau LLPS-promoting effect for any other divalent transition metal ions tested, including Mn2+, Fe2+, Co2+, Ni2+, and Cu2+. We also demonstrate that multiple zinc-binding sites on tau are involved in the LLPS-promoting effect and provide insights into the mechanism of this process. Zinc concentration is highly elevated in AD brains, and this metal ion is believed to be an important player in the pathogenesis of this disease. Thus, the present findings bring a new dimension to understanding the relationship between zinc homeostasis and the pathogenic process in AD and related neurodegenerative disorders.

(University of Bath) For the first time, labs around the world can 3D print their own precision microscopes, thanks to an open-source design created at Bath.

Mozart once called the pipe organ the “king of instruments” and Hong Kong has musical royalty sitting in the heart of Tsim Sha Tsui.

It is hard to miss the pipe organ when you are inside the Cultural Centre Concert Hall. With its four manuals, 93 stops and 8,000 pipes, it can produce an exceptional array of timbre and volume.

“The pipe organ is the ‘pearl’ of a concert hall,” explained pipe organist Chiu Siu-ling.

“Its enormous range of sounds, coupled with a huge variety of tone colours, creates a remarkable musical experience equivalent to that of an orchestra. It is the king of instruments.”

Star performer

The four-storey tall pipe organ was hand-made by famed Austrian manufacturer Rieger Orgelbau and installed when the Cultural Centre was built 30 years ago. It has attracted several world-renowned performers to Hong Kong over the years.

“When we built it in 1989, it was the first, huge mechanically operated organ in Asia. I think it is still our biggest organ we have ever built in Asia,” Rieger pipe organ maintenance technician Gerhard Pohl said.

He added that the instrument is also remarkably versatile.

“There are many organs they are built just for one musical style. On this organ, you can play everything, even jazz music.”

Mr Pohl comes to Hong Kong once a year to give the 30-year-old organ its annual health check. In between visits by the manufacturer’s technicians, William Wen ensures the Cultural Centre’s star performer remains in tip-top condition.

Top tuner

Mr Wen is Hong Kong’s only pipe organ maintenance technician. He carries out routine checks on the instrument and tunes it every month.

“Keeping it in tune is my responsibility. I take care of it.”

Mr Wen was one of the first in Hong Kong to learn the instrument in the 1980s. He became interested in pipe organ maintenance after a visit to an organ manufacturing company in Europe.

He recalled that in the ‘80s, organists in Hong Kong were few and far between. He was called upon to test the Cultural Centre organ before the grand opening, making him one of the first organists to play it.

“It was dark in the hall, so at first, I only noticed the organ’s keys. When I got closer, I was astounded by just how big the instrument was.”

Mr Wen takes up to five hours per maintenance visit to thoroughly check the pipes and tune the organ. He explained that the organ is regularly updated and was fitted with an electrical coupler system, providing greater flexibility in switching between lighter and stronger key actions as desired by the player.

“It has been updated a few times. In 2010, the organ was installed with an electrical coupler system. I used to get someone to press the keys for me while I would tune it from inside. But now, I just need a mobile phone on which I can tune it by myself.”

Musical legacy

To promote organ music and nurture local organists, the Cultural Centre has been organising the “King of the Instruments” Pipe Organ Education Series annually since 1999. Now the programme’s principal instructor, Ms Chiu has been teaching from the outset.

“People are not allowed to touch the instrument in a lot of other concert halls, and they seldom hold pipe organ concerts. This is actually not good for the organ. It has to be played to keep it in good condition or the keys and parts will become hard and old. This inspires me teach and let more and more musicians learn and play the instrument,” Ms Chiu explained.

More than 300 organists have so far been trained on the Cultural Centre’s organ. But it has also played something other than music - it has played Cupid too.

Like-minded musicians

Pipe organist Simon Chan met his wife, Shirley Cheng, through the programme.

“I joined the Pipe Organ Education Series in 2000. After that, I continued learning the organ with Ms Chiu and eventually became one of the course tutors. I met my wife in 2003 on the course.”

Ms Cheng was also a student on the course. She switched majors from information technology to music and that fateful decision led to meeting her husband.

“He asked me to watch him play. He was playing a big piece which was powerful and loud, and that was when I fell for his charms.”

The couple decided to embark on a life journey together and now hope to pass on their love of music and the pipe organ to their children.

“I wish for my kids to learn music too and to find out more about the pipe organ. This instrument brought their father and mother together and I want them to know our story,” said Ms Cheng.

The organist-music teacher duo also hopes to share the joy of the pipe organ with the rest of the community.

Children gain a valuable insight into Hong Kong’s waterworks by directing the flow of water at an attraction designed to emulate the water cycle at the Water Supplies Department’s brand new H2OPE Centre.

They learn how rain passes through catchwaters in mountains and is filtered and distributed to people’s homes at the attraction, one of the 54 games or displays at the water education centre.

Kids can also try their hand at a fishing simulator to learn about tips and advice on fishing in reservoirs and discover ways to recycle and save water at other exhibits of the 720-sq m centre, which opened in December.

“It is extremely fun. We do not have this at school. I know how to save water now,” student Kim Lam said.

“Usually, we sit in a classroom and answer questions. But now we can learn about water in Hong Kong by playing games. It is excellent,” fellow student Alan Zeng added.

Children can also watch immersive videos at the centre’s 3D dome theatre.

Deeper understanding

The department hopes the centre will raise public awareness about water conservation.

“Its exhibits, live demonstrations and interactive games help visitors gain more insight into Hong Kong’s water resources,” Water Supplies Department Senior Engineer Irene Tong explained.

People can also visit the city’s important waterworks facilities such as the Waterworks Heritage Trails and the High Island Reservoir in Sai Kung, by joining the department’s Excursion with Water Save Dave. 

Water Save Dave is the department’s mascot to help promote a water conservation culture in the community.

Water Supplies Department Engineer Fion Chan said: “Water Save Dave is blue and shaped like a water drop to encourage us to cherish every single drop of water.

“We hope that guided tours of waterworks facilities will raise the public’s awareness about water resources and conservation.”

(American Association for Cancer Research) Combining intratumoral electroporation of interleukin-12 (IL-12) DNA (tavokinogene telseplasmid, or TAVO) with the immune checkpoint inhibitor pembrolizumab (Keytruda) led to clinical responses in patients with immunologically quiescent advanced melanoma, according to results from a phase II trial.

The Hong Kong Special Administrative Region (HKSAR) Government welcomes the promulgation of the Meteorological Development Plan ...

Do you know which main gases are contained in the composition of air? Under climate change and global warming, carbon dioxide ...

(Anglia Ruskin University) A new study has found an association between low average levels of vitamin D and high numbers of COVID-19 cases and mortality rates across 20 European countries.

(Michigan Medicine - University of Michigan) Now, as hospitals across the country start to return to doing non-emergency operations that keep their beds full and their books balanced, they need to think carefully about what resources each of those procedures will need as the pandemic continues. A new guide could help them prioritize and plan. Created by poring over seven years' worth of data from 17 common operations in dozens of hospitals, it's available for free for any hospital to use.

(Rutgers University) A Rutgers engineer has created a mathematical model that accurately estimates the death toll linked to the COVID-19 pandemic in the United States and could be used around the world.

(Carnegie Mellon University) A new study sought to determine how the impact of recommender systems (also called recommenders) is affected by factors such as product type, attributes, and other sources of information about products on retailers' websites. The study found that recommenders increased the number of consumer views of product pages as well as the number of products consumers consider, but that the increase was moderated by product attributes and review ratings.

(University of Warwick) Warm winter spells have increased in frequency and duration two- to three times over since 1878, according to scientists led by the University of Warwick.

(Max Planck Institute for the Science of Human History) Three 16th-century skeletons from a mass burial in Mexico City highlight the role of the transatlantic slave trade in introducing and disseminating new pathogens to the Americas. Researchers from the Max Planck Institute for the Science of Human History and Escuela Nacional de Antropología e Historia in Mexico analyzed skeletal features, genetic data and isotopes to explore the life history of three enslaved Africans and explore the wide-ranging impacts of massive forced migration.

(University of Chicago Press Journals) Extensive cooperation among biologically unrelated individuals is uniquely human. It would be surprising if this uniqueness were not related to other uniquely human characteristics, yet current theories of human cooperation tend to ignore the human aspects of human behavior. This paper presents a theory of cooperation that draws on social, cultural, and psychological aspects of human uniqueness for which current theories have little or no explanation.

(University of Southern Denmark) Investing in the future: Researchers show how cannibalism among the invasive comb jelly enables adults to survive severe conditions at the edge of their ecological range with implications for the use and evolutionary origins of cannibalism.

(European Geosciences Union) A new declaration endorsed by EGU and other international geoscience societies affirms the commitment of the Earth, planetary and space science community to support and promote scientific knowledge and research for the benefit of humanity.

(Florida State University) Florida State University and partner universities investigated current baseline conditions in the southern Gulf to create a series of maps and guides that detail the distribution of carbon, nitrogen and the carbon-14 isotope.

There aren’t a ton of synonyms for the word “hypocrisy.” I’ve become aware of this problem ever since I began writing about the Tara Reade–Joe Biden situation. I keep gravitating towards phrases such as “despicable hypocrisy,” or “partisan hypocrisy,” or “unconscionable hypocrisy,” but you can only go to the well so often. Really, though, I’m not sure how else to describe the actions of someone like Senator Dianne Feinstein.You might recall that it was Feinstein, the ranking member of the Judiciary Committee, who withheld Christine Blasey Ford's allegation of sexual misconduct against Supreme Court nominee Brett Kavanaugh from the Senate so that it could not be properly vetted, in a last-ditch effort to sink the nomination.Feinstein knew that Ford's credibility was brittle -- the alleged victim could not tell us where or when the attack occurred, hadn’t mentioned Kavanugh’s name to anyone for over 30 years, and offered nothing approaching a contemporaneous witness.At first, Feinstein did not want to provide Ford’s name, or a place or time of the alleged attack, or allow the accused to see any evidence against him, denying him the ability to answer the charges.Henceforth this brand of justice could be referred to as “The Joe Biden Standard,” since it’s exactly the kind of show trial the presumptive Democratic nominee promises college kids via Title IX rules.When finally asked about Reade yesterday, Feinstein responded: “And I don’t know this person at all who has made the allegations. She came out of nowhere. Where has she been all these years? He was vice president.”To put this in perspective, when Ford came forward “out of nowhere,” Feinstein said: “Victims must be able to come forward only when they are ready.”What’s changed?During the Kavanaugh hearings Feinstein noted that “sharing an experience involving sexual assault — particularly when it involves a politically connected man with influence, authority and power — is extraordinarily difficult.”Is Biden not a politically connected man with influence, authority, and power? Feinstein is now arguing the opposite: She is saying we should dismiss Reade’s allegations because she failed to come forward against a powerful man earlier.But to answer Feinstein’s question about what Reade has been “up to” the past 27 years: Well, she’s been telling people that Biden had engaged in sexual misconduct. She relayed her story to her former neighbor, her brother, her former co-worker, and at least two other friends. It is also likely that her mother called Larry King Live asking for advice for her daughter the year of the alleged attack.Yesterday a document uncovered by local journalists in California -- somehow missed by Barack Obama’s crack vetting team -- shows Reade’s ex-husband bolstering her claim in 1996 divorce proceedings: “On several occasions [Reade] related a problem that she was having at work regarding sexual harassment, in U.S. Senator Joe Biden's office.”The reaction to the divorce papers has been extraordinary. Biden defenders argue that because Reade alleged “sexual harassment” -- a catch-all term used in the 1990s when men were getting away with despicable behavior far more often -- it proves her story has changed. Biden, through his deputy campaign manager Kate Bedingfield, alleges that “more and more inconsistencies” come up every day.Even if Reade didn't tell everyone everything that allegedly happened every time she mentioned the incident, that doesn’t definitively prove anything. If it did, none of us would have ever heard the name Christine Blasey Ford.Indeed, at time of Ford’s evolving story, there was a slew of journalists taking deep dives into the unreliability of memory and trauma and complexities of relaying assault allegations. I assume that science hasn’t changed in two years.Let’s also not forget that, despite Ford’s inconsistencies, Biden still argued that Kavanaugh should be presumed guilty. Why shouldn’t he?It is also quite amazing to see Biden’s defenders implicitly contending that Reade is only credibly claiming that she was sexually harassed for nearly 30 years, so her story must be politically motivated.Even if we concede that Reade is a wily Sanders operative or Putin stooge, what political motive could Reade possibly have had back in 1993 -- after working for Biden -- to smear the senator? What motive did she have to repeat that story to her family before Sanders was a candidate or Putin was running Russia?By the way, liberals have never argued that political motivations should be disqualifying. Ford came forward, by her own admission, because she did not believe the man who had allegedly assaulted her in high school should be given a seat on highest court in the land. Reade says she doesn’t want a man who allegedly assaulted her -- when he was in his 50s -- to hold the most powerful office in the world.Feinstein, of course, isn’t the only one to engage in this kind of transparent double standard. When asked about Reade, the idealist Alexandria Ocasio-Cortez, said, “I’m not sure. Frankly, this is a messy moment, and I think we need to acknowledge that -- that it is not clear-cut.”Where was all this hand-wringing and caution over the messiness of sexual-assault claims when nearly every Democrat and all their allies in the press were spreading Julie Swetnick’s alleged “gang rape” piece? Nowhere.AOC, whose position on Biden has evolved, invited Ana Maria Archila, the women who had famously cornered a weak-kneed senator Jeff Flake in an elevator and yelled at him about Kavanaugh, to the 2019 State of the Union address. Archila now says, “I feel very trapped.”I bet.People point out that there are numerous sexual-misconduct allegations leveled at Donald Trump. Indeed. If they haven’t yet, news outlets should scrutinize and investigate the credibility of those allegations, as they did for Biden but not for Kavanaugh. But it’s important to remember that Trump accuser E. Jean Carroll was given immediate and widespread coverage on cable news, while Reade reportedly wasn’t asked to tell her story by any major network -- save Fox News -- until this week.Of course, most Biden defenders are being purposely obtuse about the debate -- Mona Charen’s recent column is an excellent example. The problem isn’t that Biden is being treated unjustly, or that he should be treated unjustly; it’s that he is being treated justly by the same people who treat others unjustly. Democrats have yet to explain why Biden is afforded every benefit of the doubt but not Kavanaugh, and not millions of college students.Public figures such as Biden have every right to demand fair hearings and due process. Voters have every right to judge the credibility of both accuser and accused. Many women are victims. Many women are victims who are powerless to prove it. And some women are frauds. You can’t keep demanding that our political system adjudicate similar incidents under two completely differ set of rules. It’s untenable.

The budget carrier will begin conducting temperature checks via touchless thermometers on June 1. Passengers have to start wearing masks Friday.

The streets of Chicago may be largely empty as residents hunker down from coronavirus but some of the city's most deprived neighborhoods are still echoing to the sound of deadly gunfire and raucous partying. While significant falls in crime have been one of the few positive side effects of lockdowns in much of the United States and elsewhere, they have barely made a dent in the homicide rate in Chicago, a city that has long recorded the most murders in the country. Chicago police say 56 murders were committed in April despite statewide stay-at-home orders -- only a fraction lower than the 61 for the same month in 2019 -- while last weekend, the first of the new month, four people were killed and 46 others shot and wounded.

Alumni inspired by the scientific response to the SARS outbreak are developing a platform to help researchers collaborate on global challenges.

(Osaka University) Researchers from Osaka University and Mandom Corporation succeeded in generating immortalized myoepithelial cells in human eccrine sweat glands, providing a novel test system for research on human sweating.

(American Association for the Advancement of Science) While an effective vaccine for the SARS-CoV-2 virus is likely many months away, development could be accelerated by conducting controlled human infection (CHI) studies -- which are increasingly being considered by the scientific community due to the urgent need.

Teri L. Hernandez
May 1, 2016; 29:82-88
From Research to Practice

Cynthia Payne
Aug 1, 2001; 14:
Preface

Daren Anderson
Jan 1, 2007; 20:10-16
Feature Articles

Apr 1, 2004; 17:97-101
Articles

Russell E. Glasgow
Apr 1, 2001; 14:
Feature Articles

As the pandemic ebbed in China, alumni from the region raised more than $2.1 million to send crucial protective gear to New York healthcare workers.

13 April 2018

Invitation Only Research Event

Research Event

Event participants

Phil Bloomer, Executive Director, Business & Human Rights Resource Centre
Julie Broome, Director, Ariadne Network
Allison Corkery, Director of Rights Claiming and Accountability Program, Centre for Economic and Social Rights; Atlantic Fellow for Social and Economic Equity, London School of Economics
Chair: Sonya Sceats, Associate Fellow, International Law Programme

12 June 2019

Research Event

Event participants

Douglas, Legal Director, GCHQ
Zhixiong Huang, Luojia Chair of International Law, Wuhan University
Nemanja Malisevic, Director of Digital Diplomacy, Microsoft
Harriet Moynihan, Associate Fellow, International Law Programme, Chatham House
Chair: Elizabeth Wilmshurst, Distinguished Fellow, International Law Programme, Chatham House

2 December 2019

Hostile cyber operations by one state against another state are increasingly common. This paper analyzes the application of the sovereignty and non-intervention principles in relation to states’ cyber operations in another state below the threshold of the use of force. 

The canonical pathway of eicosanoid production in most mammalian cells is initiated by phospholipase A2-mediated release of arachidonic acid, followed by its enzymatic oxidation resulting in a vast array of eicosanoid products. However, recent work has demonstrated that the major phospholipase in mitochondria, iPLA2γ (patatin-like phospholipase domain containing 8 (PNPLA8)), possesses sn-1 specificity, with polyunsaturated fatty acids at the sn-2 position generating polyunsaturated sn-2-acyl lysophospholipids. Through strategic chemical derivatization, chiral chromatographic separation, and multistage tandem MS, here we first demonstrate that human platelet-type 12-lipoxygenase (12-LOX) can directly catalyze the regioselective and stereospecific oxidation of 2-arachidonoyl-lysophosphatidylcholine (2-AA-LPC) and 2-arachidonoyl-lysophosphatidylethanolamine (2-AA-LPE). Next, we identified these two eicosanoid-lysophospholipids in murine myocardium and in isolated platelets. Moreover, we observed robust increases in 2-AA-LPC, 2-AA-LPE, and their downstream 12-LOX oxidation products, 12(S)-HETE-LPC and 12(S)-HETE-LPE, in calcium ionophore (A23187)-stimulated murine platelets. Mechanistically, genetic ablation of iPLA2γ markedly decreased the calcium-stimulated production of 2-AA-LPC, 2-AA-LPE, and 12-HETE-lysophospholipids in mouse platelets. Importantly, a potent and selective 12-LOX inhibitor, ML355, significantly inhibited the production of 12-HETE-LPC and 12-HETE-LPE in activated platelets. Furthermore, we found that aging is accompanied by significant changes in 12-HETE-LPC in murine serum that were also markedly attenuated by iPLA2γ genetic ablation. Collectively, these results identify previously unknown iPLA2γ-initiated signaling pathways mediated by direct 12-LOX oxidation of 2-AA-LPC and 2-AA-LPE. This oxidation generates previously unrecognized eicosanoid-lysophospholipids that may serve as biomarkers for age-related diseases and could potentially be used as targets in therapeutic interventions.

Coenzyme Q (Qn) is a vital lipid component of the electron transport chain that functions in cellular energy metabolism and as a membrane antioxidant. In the yeast Saccharomyces cerevisiae, coq1–coq9 deletion mutants are respiratory-incompetent, sensitive to lipid peroxidation stress, and unable to synthesize Q6. The yeast coq10 deletion mutant is also respiratory-deficient and sensitive to lipid peroxidation, yet it continues to produce Q6 at an impaired rate. Thus, Coq10 is required for the function of Q6 in respiration and as an antioxidant and is believed to chaperone Q6 from its site of synthesis to the respiratory complexes. In several fungi, Coq10 is encoded as a fusion polypeptide with Coq11, a recently identified protein of unknown function required for efficient Q6 biosynthesis. Because “fused” proteins are often involved in similar biochemical pathways, here we examined the putative functional relationship between Coq10 and Coq11 in yeast. We used plate growth and Seahorse assays and LC-MS/MS analysis to show that COQ11 deletion rescues respiratory deficiency, sensitivity to lipid peroxidation, and decreased Q6 biosynthesis of the coq10Δ mutant. Additionally, immunoblotting indicated that yeast coq11Δ mutants accumulate increased amounts of certain Coq polypeptides and display a stabilized CoQ synthome. These effects suggest that Coq11 modulates Q6 biosynthesis and that its absence increases mitochondrial Q6 content in the coq10Δcoq11Δ double mutant. This augmented mitochondrial Q6 content counteracts the respiratory deficiency and lipid peroxidation sensitivity phenotypes of the coq10Δ mutant. This study further clarifies the intricate connection between Q6 biosynthesis, trafficking, and function in mitochondrial metabolism.

Beatriz Rocha
Apr 1, 2020; 19:574-588
Research

Bokai Song
Apr 28, 2020; 0:RA120.001981v1-mcp.RA120.001981
Research

Yafeng Zhu
Mar 23, 2020; 0:TIR119.001646v1-mcp.TIR119.001646
Technological Innovation and Resources

Chia-Feng Tsai
May 1, 2020; 19:828-838
Research

Invitation Only Research Event