Summary

Mammalian eyes are exposed to visible light but cannot perform photosynthesis. Here, we show that introducing a nanoscale, structurally and functionally preserved thylakoid system, LEAF (light-reaction enriched thylakoid NADPH-foundry), into corneal cells enables light-driven bona fide photosynthetic production of NADPH and ATP, similar to plant leaves, which alleviates oxidative stress and inflammation. LEAF acts in two domains. Intracellularly, it integrates with host cells to supply NADPH and ATP via intact photosynthetic electron transport, restoring redox balance. Extracellularly, photosynthesized NADPH enhances endogeneous antioxidant enzyme activity and reduces reactive oxygen species in the local environment. These results establish a strategy for using light as an energy input in mammalian metabolic systems and suggest a possible cross-kingdom, endosymbiosis-like interaction in which animal cells derive functional benefits from plant-derived photosynthetic neo-organelles.

Abstract

Electrical signalling across distinct populations of brain cells underpins cognitive and emotional function. However, approaches that selectively regulate electrical signalling between two cellular components of a mammalian neural circuit remain sparse. Here we engineered an electrical synapse composed of two connexin proteins found in Morone americana (white perch fish)—connexin 34.7 and connexin 35—to accomplish mammalian circuit modulation. By exploiting protein mutagenesis, devising a new in vitro system for assaying connexin hemichannel docking, and performing computational modelling of hemichannel interactions, we uncovered a structural motif that contributes to electrical synapse formation. Targeting this motif, we designed connexin 34.7 and connexin 35 hemichannels that dock with each other to form an electrical synapse but not with other major connexins expressed in the mammalian central nervous system. We validated this electrical synapse in vivo using worms (Caenorhabditis elegans) and mice (Mus musculus). We demonstrate that it can strengthen communication across neural circuits composed of pairs of distinct cell types and modify behaviour accordingly. Thus, we establish ‘long-term integration of circuits using connexins’ (LinCx) for precision circuit editing in mammals.

Abstract

Purple bacteria are a diverse group of photosynthetic organisms that can capture and convert light energy with high quantum efficiency across a variety of ecological niches. They absorb light via an array of antenna proteins, primarily light-harvesting complex 2 (LH2), and rapidly transport the energy to the reaction center, where charge separation occurs. LH2 typically consists of eight or nine subunits that each contain three bacteriochlorophyll and one carotenoid. In the marine species Marichromatium (Mch.) purpuratum, the LH2 subunits bind an additional carotenoid, boosting absorbance in the blue where the underwater solar spectrum peaks. In order to accommodate the additional carotenoid, LH2 from Mch. purpuratum consists of only seven subunits, unique among known LH2. Using ultrafast transient absorption (TA) spectroscopy, time-resolved fluorescence, and steady-state techniques, we investigated the effects of these structural differences on the energy transfer dynamics of LH2 from Mch. purpuratum. Our results show, relative to other species, significantly slower rates of energy transfer within LH2 and an excited-state manifold likely to also slow energy transfer between LH2. LH2 from Mch. purpuratum is therefore tuned to match the solar spectrum of its ecological niche, suggesting that the variations in the molecular organization of these antenna proteins may be primarily for optimal light absorption.

cross-posted from: https://sopuli.xyz/post/7625705

According to the linked article, 72 studies suggest that wi-fi radiation harms/kills #bees -- and by some claims is a threat to their continued existence. I suppose if extinction were really a likely risk there would be widespread outrage and bee conservationists taking actions. It seems there is a lack of chatter about this. This thread also somewhat implies disinterest in even having wi-fi alternatives.

In any case, does anyone think this is a battle worth fighting? Some possible off-the-cuff actions that come to mind:

• ban the sale of wi-fi devices bigger than a phone in Europe¹ if they do not also comply with these conditions:
  • include an ethernet port as well. So e.g. macbooks would either have to bring back the ethernet port or nix wi-fi (and obviously Apple wouldn’t nix Wi-Fi).
  • have a physical wi-fi toggle switch on the chassis (like Thinkpads have)
• force public libraries with Wi-Fi to give an ethernet port option so library users at least have the option of turning off their own wi-fi emissions.
• ban the sale of Wi-Fi APs that do not have:
  • a configurable variable power setting that is easily tunable by the user; maybe even require a knob or slider on the chassis.
  • bluetooth that is internet-capable
• force phones that include wi-fi to also include bluetooth as well as the programming to use bluetooth for internet. Bluetooth routers have existed for over a decade but they are quite rare.. cannot be found in a common electronics shop.

Regarding bluetooth, it is much slower than wi-fi, lower range, and probably harder to secure. But nonetheless people should have this option for situations where they don’t need wi-fi capability. E.g. when a phone is just sitting idle it could turn off wi-fi and listen over bluetooth for notifications.

I suspect the 1st part of this quote from the article explains the lack of concern:

“The subject is uncomfortable for many of us because it interferes with our daily habits and there are powerful economic interests behind mobile communication technology.”

1. I say /Europe/ because it’s perhaps the only place where enough people would be concerned and where you also have the greatest chance of passing pro-humanity legislation (no “Citizens United” that human needs have to compete with).

Hey, so I just fu***g quit my new job rn. I got offered something better last minute but didn’t wanna be a dick and cancel on them at the last minute, so I went through with it anyways and then QUIT RIGHT AFTER THEY HIRED ME LMFAO. It felt so good man, total payback for all those times i wasted my time interviewing only to never get the gig.

This article describes using lipid nanoparticles (LNPs) containing silencing RNA (siRNA) to slow or prevent the spread of cancerous multiple myeloma cells through the body.

What I found interesting about this approach is that these LNPs do not target the cancerous cells themselves, but rather targets healthy endothelial cells lining blood vessels in the body. The mechanism of action is to reduce the expression of a protein (CyPA) that cancer cells use to aid their spread through the body. So, these LNPs are simply used to help contain and localize the cancerous growth while traditional cancer treatments are used to treat the malignant cells.

A significant challenge for this approach going forward is tuning the targeting and biodistribution of the LNPs. Most LNP treatments end up in either the liver or spleen where they transfect cells in those organs and express protiens. I don't have direct experience with siRNA molecules, but transfecting epithelial cells in a lasting way could prove difficult as it scales up from mouse models.

doi: https://dx.doi.org/10.1073/pnas.2215711120

Getting therapeutics to cross the blood-brain barrier is one of the biggest hurdles to many investigational neuroscience macromolecules. This approach of using a proven mechanism of action (ultrasound) in a device that is easily implantable and does not need to later be removed looks promising.

doi: https://dx.doi.org/10.1126/sciadv.adg6075

Some recent evidence points to the Earth's magnetic field playing a part in preferentially selecting right-handed chirality in RNA precursors. This work is not complete though as not every nucleotide can be made from this process yet, but it is so far, the best explanation available as to why genetic material and amino acids are exclusively R and L (respectively) oriented.