An array of scientific evidence suggest that in some cases, the bacteria in your gut–your microbiome–could be tied to neurological and psychological disorders and differences, from anxiety and autism to Parkinson's and schizophrenia. The journal Science published a survey of the field and the Cambridge, Massachusetts start-up Holobiome that hopes to use insight into this "psychobiome" to develop treatments for depression, insomnia, and other conditions with a neurological side to them. From Science:

For example, many people with irritable bowel syndrome are also depressed, people on the autism spectrum tend to have digestive problems, and people with Parkinson’s are prone to constipation.

Researchers have also noticed an increase in depression in people taking antibiotics—but not antiviral or antifungal medications that leave gut bacteria unharmed. Last year, Jeroen Raes, a microbiologist at the Catholic University of Leuven, and colleagues analyzed the health records of two groups—one Belgian, one Dutch—of more then 1000 people participating in surveys of their types of gut bacteria. People with depression had deficits of the same two bacterial species, the authors reported in April 2019 in Nature Microbiology.

Researchers see ways in which gut microbes could influence the brain. Some may secrete messenger molecules that travel though the blood to the brain. Other bacteria may stimulate the vagus nerve, which runs from the base of the brain to the organs in the abdomen. Bacterial molecules might relay signals to the vagus through recently discovered “neuropod” cells that sit in the lining of the gut, sensing its biochemical milieu, including microbial compounds.

A family in lockdown performs the Beatles' "Come Together." Read the rest

Prime Minister Justin Trudeau says Canada will not pay the full price for medical masks that do not live up to medical standards.

Police in Haiti are investigating allegations that the president of the national football federation raped teenage girls.

Former Proteas head coach Ray Jennings is adamant Aiden Markram should be chosen as Faf du Plessis' replacement as captain of the Test team.

Other Space Synopsis Other Space is a Science Fiction comedy television series produced by Yahoo that premiered in April of 2015. Created by Paul Feig (Freaks and Geeks) Other Space is set in the early 22nd century and follows the story of the inexperienced crew aboard UMP Cruiser on a routine space exploratory mission. In […]

The Protectors (1972) Synopsis The Protectors (1972) was an action thriller television series produced by ITV that premiered in September of 1972. The Protectors (1972) was a British action thriller series created by Gerry Anderson (Thunderbirds) about an international group of rich troubleshooters. Contessa di Contini (played by Nyree Dawn Porter), Paul Buchet (played by […]

Do you know that feeling when you are hyped and ready to take on a new challenge? You are taken over by a surge of motivation and excitement and you’ve made a commitment you fully intend to stick to. It sounds familiar, right? Perhaps you declared your intention to dedicate more time to self-care, or […]

The post 7 Must-Do Hacks for When Your Motivation Dips appeared first on Dumb Little Man.

Mother’s Day is just around the corner and finding the perfect gift for such a special occasion can be a really overwhelming task, particularly if you’re a last minute shopper. That’s why, to help you out, we’re sharing with you the best Mother’s Day gift ideas you can give to every supermom on your list. […]

The post DumbLittleMan’s Ultimate Gift Guide for Mother’s Day 2020 appeared first on Dumb Little Man.

Spotify will gain more than 10 million US listeners in 2020   February 25, 2020 (New York, NY) – Pandora is no longer the most popular music streaming service in the […]

Hi, Amazon. We’ve had a long history, ever since I ordered those first books and DVDs to be delivered to my college mailbox. You indulged my whims, from paleo cooking to crocheting, and you deposited a solid amount of cash in my bank account at the end of every month. Not to mention that fat …

Dear Amazon, We’re Breaking Up. It’s Not Me. It’s You. Read More »

The post Dear Amazon, We’re Breaking Up. It’s Not Me. It’s You. appeared first on Adventurous Kate.

With a bright, 8.2-inch HD display and the flexibility to work in almost any vehicle, the Lanmodo Automotive Vast Night Vision System is a near-perfect alternative to factory-installed systems.

The post Brighten Up Your After-Dark Road-Tripping with Lanmodo’s Vast Automotive Night Vision System appeared first on Vagabondish.

By choosing the right brands and most versatile fabrics, you can pack the same men's travel clothes no matter where you're headed.

The post The Men’s Travel Clothes I Pack No Matter Where I’m Headed appeared first on Vagabondish.

People are always curious about work-from-home (WFH), remote working setups. So, I posted a Basecamp message asking our employees to share a photo of their home office, desk, table, whatever. Here’s what came in. First, the ask: And the answers, in the order they came in: Andy Didorosi, Marketing Justin White, Programmer Jonas Downey, Designer… keep reading

In this livesteam, David and I answer audience questions about how to work remotely. At Basecamp we’ve been working remotely for nearly 20 years, so we have a lot of experience to share. This nearly 2-hour video goes into great detail on a wide variety of topics. Highly recommended if you’re trying to figure out… keep reading

For many, moving from everyone’s-working-from-the-office to everyone’s-working-at-home isn’t so much a transition as it is a scramble. A very how the fuck? moment. That’s natural. And people need time to figure it out. So if you’re in a leadership position, bake in time. You can’t expect people to hit the ground running when everything’s different.… keep reading

We’ve been teaching people how to do remote work well for the better part of two decades. We wrote a whole book about the topic in 2013, called REMOTE: Office Not Required. Basecamp has been a remote company since day one, and our software is sold as an all-in-one toolkit for remote work. Yeah, we’re… keep reading

The men with the pinkest jumpsuits in British comedy are back with another series of their outrageously odd sketch show, starting tonight at 9pm on BBC Two.

Part of the Food for thought promo for the BBC UK Homepage

A couple weeks ago, my pals at Twitter were kind enough to invite me in to visit with their (rapidly growing) team. The topic was meetings, so I used it as an opportunity to publicly premiere a talk I've been presenting to private clients over the past few months.

I hope you'll enjoy, Broken Meetings (and how you'll fix them).

Slides:

Supplementary links and commentary forthcoming, but I wanted to go ahead and post the talk as quickly as the video was available. Special thanks to Michelle, Jeremy, and the crackerjack Twitter crew for a swell afternoon.

I really like this talk and sincerely hope you will find it useful in helping to un-break your own meetings.

[update 2011-01-18 @ 16:07:40: We're up!]

5by5 Live

Before Christ was a corporal, Dan Benjamin was already a bit of a hero to me.

Since the early aughts–long before his insanely great 5by5.tv podcast network–Dan’s Hivelogic Enkoder was saving us millions of spam messages. His thoughtful tutorials on OS X (including unmissable advice on doing sane installs of MySQL and Rails, among others) are among the best on the web. His CSS has been widely stolen and reused without acknowledgment by thieves as diverse as other people and me. And his polymath posts on everything from Buddhism to The Paleo Diet to how to record a “Double-ender” have shown a charming combination of curiosity and empathy that, amongst numerous other reasons, clearly makes Dan a better human than me.

A propos of nothing, Dan’s also the guy who conducted one of (mp3) the three best interviews with me in which it’s been my good fortune to participate.1

Today, I’m honored to say that Dan and I are starting a thing together.

If it suits you, drop by 5by5.tv/live in about 35 minutes–at Noon Eastern/9am Pacific–to find out what we’re up to. I think it might be good. I’ll just say I’m as excited about this as I’ve been about any new project I’ve started in the past year or so.

Anyway. You can judge for yourself. Whether you can tolerate me or otherwise, definitely do not miss the work Dan’s doing at 5by5. Because it really is outstanding and very polished stuff.

As for our thing? My own goal, to paraphrase a bit from that interview with Dan, is to help you get excited, get better–and then?–Back to Work.

More soon. Thanks.

And...we're up

Back to Work | Ep.#1: Alligator in the Bathroom

Download MP3 of "'Back to Work,' Ep. 1"

In the inaugural episode of Back to Work, Merlin Mann and Dan Benjamin discuss why they’re doing this show, getting back to work instead of buying berets, the lizard brain, and compare the Shadow of the Mouse to San Francisco, and eventually get to some practical tips for removing friction.

It's a start.

Sexy Audio RSS Feed
Sexy Subscription via iTunes

Episode Links

• Welcome to BrettTerpstra.com, home of Brett Terpstra and his nerdery
• carlhuda/janus – GitHub
• practically efficient — technology, workflows, life
• MacSparky – Blog
• The Brooks Review
• And now it’s all this
• Dan Rodney’s List of Mac OS X Keyboard Shortcuts & Keystrokes
• 43f Podcast: John Gruber & Merlin Mann’s Blogging Panel at SxSW | 43 Folders
• waffle software · ThisService
• One Thing Well
• html2text: THE ASCIINATOR (aka html2txt)
• The Conversation #27: Missionless Statements – 5by5

After seven weeks, Honda Canada in Alliston will gradually begin operations next week.

Friday, May 8, 2020, marks the 75 anniversary of VE Day.

While infection rates remain steady across the region, the Simcoe Muskoka District Health Unit is reporting more than half of all 360 cases have now recovered.

The calendar may say May, but that didn't stop Mother Nature from blasting some wintry weather in Muskoka on Friday.

Police officers responding to a call about a man with a machete in Oppenheimer Park Friday afternoon found what they were looking for, and then some.

The following article, Photos Of Kim Jong Un Spark Conspiracy Theories About A Body Double…You Be The Judge, was first published on 100PercentFedUp.com.

For several weeks rumors of the North Korean dictator’s sickness and ultimately, his death, have been making their rounds in the media. North Korea’s state-run media released photos of  Kim Jong Un that were allegedly taken on May 1, at the opening of a fertilizer factory in Sunchon, N. Korea. Twitter users who’ve studied the images are […]

Continue reading: Photos Of Kim Jong Un Spark Conspiracy Theories About A Body Double…You Be The Judge ...

The following article, BREAKING: 43-Yr-Old Father Of 9, Dollar Store Sec Guard, Shot DEAD While Allegedly Trying To Enforce MI Gov Whitmer’s Face Covering Exec Order, was first published on 100PercentFedUp.com.

Will the mainstream media report about the senseless death of a 43-year-old father of nine, who would have been alive today if it were not for VP wannabe, Gretchen Whitmer's executive order that forced him to respond to a customer not wearing a face mask? 

Continue reading: BREAKING: 43-Yr-Old Father Of 9, Dollar Store Sec Guard, Shot DEAD While Allegedly Trying To Enforce MI Gov Whitmer’s Face Covering Exec Order ...

The following article, 77-Yr-Old MI Barber Defies Gov Whitmer’s Shutdown Order: ”I don’t need another mother” Shop Will Stay Open Until “Jesus walks in or until they arrest me” [VIDEO], was first published on 100PercentFedUp.com.

Emergency orders that “non-essential businesses” remain closed during the Covid-19 crisis have devastated small business owners across America. A wave of business owners across the nation are defying executive orders by their governors and opening their businesses anyhow. Yesterday, we reported about a small business owner in the state of Michigan, where Governor Gretchen Whitmer […]

Continue reading: 77-Yr-Old MI Barber Defies Gov Whitmer’s Shutdown Order: ”I don’t need another mother” Shop Will Stay Open Until “Jesus walks in or until they arrest me” [VIDEO] ...

The following article, Legal Immigrant in Michigan Sends a Message to MI Gov Whitmer and Media Criticizing Freedom-Loving Protesters, was first published on 100PercentFedUp.com.

The media and even some governors are trying to paint the Americans who are protesting to open businesses up as racists and even Nazis. The Governor of Michigan recently made a derogatory statement about the protesters implying they are racists. Painting a negative picture of the people who want their freedom and businesses demonizes our […]

Continue reading: Legal Immigrant in Michigan Sends a Message to MI Gov Whitmer and Media Criticizing Freedom-Loving Protesters ...

The following article, ‘Schiff in Panic Mode’: Sources Say Russia Probe Transcripts Affirm Officials Found Nothing on Collusion, was first published on 100PercentFedUp.com.

Transcripts of House Intelligence Committee interviews have been cleared for release, and Adam Schiff is reportedly in panic mode. Unfortunately for Schiff, top law enforcement and intel officials said they saw no evidence of collusion between the Trump campaign and Russia in the transcripts. Republicans sought and got approval for the release of the transcripts […]

Continue reading: ‘Schiff in Panic Mode’: Sources Say Russia Probe Transcripts Affirm Officials Found Nothing on Collusion ...

The following article, Texas Gov Abbott Frees Salon Owner Shelley Luther: “Criminals shouldn’t be released to prevent COVID-19 just to put business owners in their place”, was first published on 100PercentFedUp.com.

Texas Governor Greg Abbott just changed the coronavirus order to free Salon A La Mode owner Shelley Luther from jail. Abbott tweeted out a comment about the poor treatment of the business owner: Throwing Texans in jail whose biz’s shut down through no fault of their own is wrong. I am eliminating jail for violating […]

Continue reading: Texas Gov Abbott Frees Salon Owner Shelley Luther: “Criminals shouldn’t be released to prevent COVID-19 just to put business owners in their place” ...

The following article, Mother of the Year, Michelle Obama Explains How Having Kids Was A “Concession”… Had To Give Up Her “Aspirations and Dreams” [VIDEO], was first published on 100PercentFedUp.com.

While campaigning for her community organizer turned presidential candidate husband, Barack, Michelle Obama told a crowd of his supporters in Milwaukee, Wisconsin that for the first time in her life, she was proud to be an American. Four years later, Michelle Obama was a keynote speaker at the DNC convention, where she told Democrats how […]

Continue reading: Mother of the Year, Michelle Obama Explains How Having Kids Was A “Concession”… Had To Give Up Her “Aspirations and Dreams” [VIDEO] ...

The following article, Woman Shoots Three Teenage McDonald’s Workers For Telling Her She Couldn’t Eat In Dining Room Over COVID19 Restrictions, was first published on 100PercentFedUp.com.

An angry Oklahoma woman shot at a group of teenagers working at a local McDonald’s after they explained to her that the dining room was closed due to coronavirus restrictions. 32-year-old Gloricia Woody was arrested by the Oklahoma City Police and charged with the shooting. From the Oklahoma City Police -Last night, officers were called […]

Continue reading: Woman Shoots Three Teenage McDonald’s Workers For Telling Her She Couldn’t Eat In Dining Room Over COVID19 Restrictions ...

The following article, BREAKING: President Trump’s Fiery Interview On Fox & Friends…”These are dirty politicians and dirty cops…They put our nation in danger with other nations, including Russia” [VIDEO], was first published on 100PercentFedUp.com.

This morning during a nearly one hour interview with Fox & Friends, President Trump addressed the decision by the DOJ to drop the case against the innocent General Michael Flynn. Trump ripped into the “dirty politicians and dirty cops” who went after General Michael Flynn. President Trump called the players involved in the horrible plot […]

Continue reading: BREAKING: President Trump’s Fiery Interview On Fox & Friends…”These are dirty politicians and dirty cops…They put our nation in danger with other nations, including Russia” [VIDEO] ...

The following article, Obama Private Call Released: Implores Political Operatives to Help Protect Him…”We gotta make this happen”, was first published on 100PercentFedUp.com.

Michael Isikoff at Yahoo News on Friday night released audio of a call from former President Barack Obama to political operatives and the media to help protect “the rule of law” by protecting him. Obama desperately wants the Deep State and media to protect him by helping elect Joe Biden: “The fact that there is […]

Continue reading: Obama Private Call Released: Implores Political Operatives to Help Protect Him…”We gotta make this happen” ...

In Lakeshore, it may be a little while longer before a retail cannabis store opens.

Mother's Day is Sunday, but with COVID-19, it's forcing many to change their plans.

A beverage company in the U.S. is inviting moms to let out a ‘quaranscream’ this Mother’s Day on a designated ‘zero-judgement venting hotline’ for a chance to win its wine spritzers.

11 February 2020

The atypical trichromatic cyanobacterial phytochrome NpTP1 from Nostoc punctiforme ATCC 29133 is a linear tetrapyrrole (bilin)-binding photoreceptor protein that possesses tandem-cysteine residues responsible for shifting its light-sensing maximum to the violet spectral region. Using bioinformatics and phylogenetic analyses, here we established that tandem-cysteine cyanobacterial phytochromes (TCCPs) compose a well-supported monophyletic phytochrome lineage distinct from prototypical red/far-red cyanobacterial phytochromes. To investigate the light-sensing diversity of this family, we compared the spectroscopic properties of NpTP1 (here renamed NpTCCP) with those of three phylogenetically diverged TCCPs identified in the draft genomes of Tolypothrix sp. PCC7910, Scytonema sp. PCC10023, and Gloeocapsa sp. PCC7513. Recombinant photosensory core modules of ToTCCP, ScTCCP, and GlTCCP exhibited violet-blue–absorbing dark-states consistent with dual thioether-linked phycocyanobilin (PCB) chromophores. Photoexcitation generated singly-linked photoproduct mixtures with variable ratios of yellow-orange and red-absorbing species. The photoproduct ratio was strongly influenced by pH and by mutagenesis of TCCP- and phytochrome-specific signature residues. Our experiments support the conclusion that both photoproduct species possess protonated 15E bilin chromophores, but differ in the ionization state of the noncanonical “second” cysteine sulfhydryl group. We found that the ionization state of this and other residues influences subsequent conformational change and downstream signal transmission. We also show that tandem-cysteine phytochromes present in eukaryotes possess similar amino acid substitutions within their chromophore-binding pocket, which tune their spectral properties in an analogous fashion. Taken together, our findings provide a roadmap for tailoring the wavelength specificity of plant phytochromes to optimize plant performance in diverse natural and artificial light environments.

Previous studies have shown that sphingosine kinase interacting protein (SKIP) inhibits sphingosine kinase (SK) function in fibroblasts. SK phosphorylates sphingosine producing the potent signaling molecule sphingosine-1-phosphate (S1P). SKIP gene (SPHKAP) expression is silenced by hypermethylation of its promoter in acute myeloid leukemia (AML). However, why SKIP activity is silenced in primary AML cells is unclear. Here, we investigated the consequences of SKIP down-regulation in AML primary cells and the effects of SKIP re-expression in leukemic cell lines. Using targeted ultra-HPLC-tandem MS (UPLC-MS/MS), we measured sphingolipids (including S1P and ceramides) in AML and control cells. Primary AML cells had significantly lower SK activity and intracellular S1P concentrations than control cells, and SKIP-transfected leukemia cell lines exhibited increased SK activity. These findings show that SKIP re-expression enhances SK activity in leukemia cells. Furthermore, other bioactive sphingolipids such as ceramide were also down-regulated in primary AML cells. Of note, SKIP re-expression in leukemia cells increased ceramide levels 2-fold, inactivated the key signaling protein extracellular signal-regulated kinase, and increased apoptosis following serum deprivation or chemotherapy. These results indicate that SKIP down-regulation in AML reduces SK activity and ceramide levels, an effect that ultimately inhibits apoptosis in leukemia cells. The findings of our study contrast with previous results indicating that SKIP inhibits SK function in fibroblasts and therefore challenge the notion that SKIP always inhibits SK activity.

The peroxisome is a subcellular organelle that functions in essential metabolic pathways, including biosynthesis of plasmalogens, fatty acid β-oxidation of very-long-chain fatty acids, and degradation of hydrogen peroxide. Peroxisome biogenesis disorders (PBDs) manifest as severe dysfunction in multiple organs, including the central nervous system (CNS), but the pathogenic mechanisms in PBDs are largely unknown. Because CNS integrity is coordinately established and maintained by neural cell interactions, we here investigated whether cell-cell communication is impaired and responsible for the neurological defects associated with PBDs. Results from a noncontact co-culture system consisting of primary hippocampal neurons with glial cells revealed that a peroxisome-deficient astrocytic cell line secretes increased levels of brain-derived neurotrophic factor (BDNF), resulting in axonal branching of the neurons. Of note, the BDNF expression in astrocytes was not affected by defects in plasmalogen biosynthesis and peroxisomal fatty acid β-oxidation in the astrocytes. Instead, we found that cytosolic reductive states caused by a mislocalized catalase in the peroxisome-deficient cells induce the elevation in BDNF secretion. Our results suggest that peroxisome deficiency dysregulates neuronal axogenesis by causing a cytosolic reductive state in astrocytes. We conclude that astrocytic peroxisomes regulate BDNF expression and thereby support neuronal integrity and function.

Heterotrimeric G proteins are the core upstream elements that transduce and amplify the cellular signals from G protein–coupled receptors (GPCRs) to intracellular effectors. GPCRs are the largest family of membrane proteins encoded in the human genome and are the targets of about one-third of prescription medicines. However, to date, no single therapeutic agent exerts its effects via perturbing heterotrimeric G protein function, despite a plethora of evidence linking G protein malfunction to human disease. Several recent studies have brought to light that the Gq family–specific inhibitor FR900359 (FR) is unexpectedly efficacious in silencing the signaling of Gq oncoproteins, mutant Gq variants that mostly exist in the active state. These data not only raise the hope that researchers working in drug discovery may be able to potentially strike Gq oncoproteins from the list of undruggable targets, but also raise questions as to how FR achieves its therapeutic effect. Here, we place emphasis on these recent studies and explain why they expand our pharmacological armamentarium for targeting Gq protein oncogenes as well as broaden our mechanistic understanding of Gq protein oncogene function. We also highlight how this novel insight impacts the significance and utility of using G(q) proteins as targets in drug discovery efforts.

The protein-tyrosine phosphatase SHP2 is an allosteric enzyme critical for cellular events downstream of growth factor receptors. Mutations in the SHP2 gene have been linked to many different types of human diseases, including developmental disorders, leukemia, and solid tumors. Unlike most SHP2-activating mutations, the T507K substitution in SHP2 is unique in that it exhibits oncogenic Ras-like transforming activity. However, the biochemical basis of how the SHP2/T507K variant elicits transformation remains unclear. By combining kinetic and biophysical methods, X-ray crystallography, and molecular modeling, as well as using cell biology approaches, here we uncovered that the T507K substitution alters both SHP2 substrate specificity and its allosteric regulatory mechanism. We found that although SHP2/T507K exists in the closed, autoinhibited conformation similar to the WT enzyme, the interactions between its N-SH2 and protein-tyrosine phosphatase domains are weakened such that SHP2/T507K possesses a higher affinity for the scaffolding protein Grb2-associated binding protein 1 (Gab1). We also discovered that the T507K substitution alters the structure of the SHP2 active site, resulting in a change in SHP2 substrate preference for Sprouty1, a known negative regulator of Ras signaling and a potential tumor suppressor. Our results suggest that SHP2/T507K's shift in substrate specificity coupled with its preferential association of SHP2/T507K with Gab1 enable the mutant SHP2 to more efficiently dephosphorylate Sprouty1 at pTyr-53. This dephosphorylation hyperactivates Ras signaling, which is likely responsible for SHP2/T507K's Ras-like transforming activity.

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.

Mutations in retinaldehyde-binding protein 1 (RLBP1), encoding the visual cycle protein cellular retinaldehyde-binding protein (CRALBP), cause an autosomal recessive form of retinal degeneration. By binding to 11-cis-retinoid, CRALBP augments the isomerase activity of retinoid isomerohydrolase RPE65 (RPE65) and facilitates 11-cis-retinol oxidation to 11-cis-retinal. CRALBP also maintains the 11-cis configuration and protects against unwanted retinaldehyde activity. Studying a sibling pair that is compound heterozygous for mutations in RLBP1/CRALBP, here we expand the phenotype of affected individuals, elucidate a previously unreported phenotype in RLBP1/CRALBP carriers, and demonstrate consistencies between the affected individuals and Rlbp1/Cralbp−/− mice. In the RLBP1/CRALBP-affected individuals, nonrecordable rod-specific electroretinogram traces were recovered after prolonged dark adaptation. In ultrawide-field fundus images, we observed radially arranged puncta typical of RLBP1/CRALBP-associated disease. Spectral domain-optical coherence tomography (SD-OCT) revealed hyperreflective aberrations within photoreceptor-associated bands. In short-wavelength fundus autofluorescence (SW-AF) images, speckled hyperautofluorescence and mottling indicated macular involvement. In both the affected individuals and their asymptomatic carrier parents, reduced SW-AF intensities, measured as quantitative fundus autofluorescence (qAF), indicated chronic impairment in 11-cis-retinal availability and provided information on mutation severity. Hypertransmission of the SD-OCT signal into the choroid together with decreased near-infrared autofluorescence (NIR-AF) provided evidence for retinal pigment epithelial cell (RPE) involvement. In Rlbp1/Cralbp−/− mice, reduced 11-cis-retinal levels, qAF and NIR-AF intensities, and photoreceptor loss were consistent with the clinical presentation of the affected siblings. These findings indicate that RLBP1 mutations are associated with progressive disease involving RPE atrophy and photoreceptor cell degeneration. In asymptomatic carriers, qAF disclosed previously undetected visual cycle deficiency.

Cone photoreceptors in the retina enable vision over a wide range of light intensities. However, the processes enabling cone vision in bright light (i.e. photopic vision) are not adequately understood. Chromophore regeneration of cone photopigments may require the retinal pigment epithelium (RPE) and/or retinal Müller glia. In the RPE, isomerization of all-trans-retinyl esters to 11-cis-retinol is mediated by the retinoid isomerohydrolase Rpe65. A putative alternative retinoid isomerase, dihydroceramide desaturase-1 (DES1), is expressed in RPE and Müller cells. The retinol-isomerase activities of Rpe65 and Des1 are inhibited by emixustat and fenretinide, respectively. Here, we tested the effects of these visual cycle inhibitors on immediate, early, and late phases of cone photopic vision. In zebrafish larvae raised under cyclic light conditions, fenretinide impaired late cone photopic vision, while the emixustat-treated zebrafish unexpectedly had normal vision. In contrast, emixustat-treated larvae raised under extensive dark-adaptation displayed significantly attenuated immediate photopic vision concomitant with significantly reduced 11-cis-retinaldehyde (11cRAL). Following 30 min of light, early photopic vision was recovered, despite 11cRAL levels remaining significantly reduced. Defects in immediate cone photopic vision were rescued in emixustat- or fenretinide-treated larvae following exogenous 9-cis-retinaldehyde supplementation. Genetic knockout of Des1 (degs1) or retinaldehyde-binding protein 1b (rlbp1b) did not eliminate photopic vision in zebrafish. Our findings define molecular and temporal requirements of the nonphotopic or photopic visual cycles for mediating vision in bright light.

Manganese (Mn) is an essential micronutrient required for the normal development of many organs, including the brain. Although its roles as a cofactor in several enzymes and in maintaining optimal physiology are well-known, the overall biological functions of Mn are rather poorly understood. Alterations in body Mn status are associated with altered neuronal physiology and cognition in humans, and either overexposure or (more rarely) insufficiency can cause neurological dysfunction. The resultant balancing act can be viewed as a hormetic U-shaped relationship for biological Mn status and optimal brain health, with changes in the brain leading to physiological effects throughout the body and vice versa. This review discusses Mn homeostasis, biomarkers, molecular mechanisms of cellular transport, and neuropathological changes associated with disruptions of Mn homeostasis, especially in its excess, and identifies gaps in our understanding of the molecular and biochemical mechanisms underlying Mn homeostasis and neurotoxicity.