Seeking Delphi podcast host Mark Sackler is joined by panelists Liz Parrish, Aubrey de Grey, David Wood and co-moderator Keith Comito to discuss scenarios for getting to—and dealing with—a post aging future.
Johns Hopkins researchers report that a type of biodegradable, lab-engineered nanoparticle they fashioned can successfully deliver a “suicide gene” to pediatric brain tumor cells implanted in the brains of mice. The poly(beta-amino ester) nanoparticles, known as PBAEs, were part of a treatment that also used a drug to kill the cells and prolong the test animals’ survival.
In their study, described in a report published January 2020 in the journal Nanomedicine: Nanotechnology, Biology and Medicine, the researchers caution that for safety and biological reasons, it is unlikely that the suicide gene herpes simplex virus type I thymidine kinase (HSVtk)—which makes tumor cells more sensitive to the lethal effects of the anti-viral drug ganciclovir—could be the exact therapy used to treat human medulloblastoma and atypical teratoid/rhabdoid tumors (AT/RT) in children.
So-called “suicide genes” have been studied and used in cancer treatments for more than 25 years. The HSVtk gene makes an enzyme that helps restore the function of natural tumor suppression.
“If everything regenerated, there would be no death.” Richard J. Goss, Ph.D.Principles of Regeneration Richard J. Goss, Ph.D., author of Principles of Regeneration, was a visiting scientist at the MDI Biological Laboratory in the late 1960’s and early 1970’s. But is the statement that there would be no death if everything regenerated correct? The zebrafish,…
Telomerase defers the onset of telomere shortening and cellular senescence by adding telomeric repeat DNA to chromosome ends, and its activation contributes to carcinogenesis. Telomerase minimally consists of the telomerase reverse transcriptase (TERT) and the telomerase RNA (TR). However, how telomerase assembles is largely unknown. Here, we demonstrate that PES1 (Pescadillo), a protein overexpressed in many cancers, forms a complex with TERT and TR through direct interaction with TERT, regulating telomerase activity, telomere length maintenance, and senescence. PES1 does not interact with the previously reported telomerase components Reptin, Pontin, p23, and Hsp90. PES1 facilitates telomerase assembly by promoting direct interaction between TERT and TR without affecting TERT and TR levels. PES1 expression correlates positively with telomerase activity and negatively with senescence in patients with breast cancer. Thus, we identify a previously unknown telomerase complex, and targeting PES1 may open a new avenue for cancer therapy.
Telomerase is a ribonucleoprotein (RNP) enzyme that adds telomeric repeat DNA to chromosome ends (1–3). This prevents progressive shortening of telomeres caused by the failure of the DNA replication machinery to duplicate the very end of each chromosome. Once telomeres are shortened to a certain length, cells enter replicative senescence or, alternatively, undergo apoptosis, a major tumor-suppressive mechanism. Telomerase, which is required for de novo telomeric repeat DNA synthesis and telomere maintenance, is expressed in approximately 90% of cancer cells but undetectable in the majority of normal somatic cells (4–6). Thus, telomerase is thought to be a relevant factor in distinguishing cancer cells from normal cells and has become a target for cancer therapy.
Telomerase is minimally composed of the telomerase reverse transcriptase (TERT) and the telomerase RNA (TR). Studies have shown in vitro assembly of active telomerase by combining the purified RNA component with the TERT synthesized in rabbit reticulocyte extract (7–9). A few accessory proteins have been identified to associate with the active telomerase RNP complex. The molecular chaperones p23 and Hsp90 bind to human TERT (hTERT), and chemical inhibition of Hsp90 decreases telomerase activity (10, 11). However, determining whether Hsp90 is required for active telomerase assembly is difficult because chemical inhibition of a key chaperone in human cells potentially has pleiotropic and indirect effects. Assembly of human TR (hTR) and hTERT into catalytically active telomerase is facilitated by the adenosine triphosphatases Reptin and Pontin (12). Pontin knockdown (KD) reduces telomerase activity and hTR levels.
“The team used an advanced imaging technology called “zero-mode waveguide single-molecule fluorescence microscopy,” which they have adapted in recent years for real-time tracking of RNAs and proteins. Ribosomes are made of both RNA and proteins, reflecting a molecular partnership that is widely believed to go back nearly to the dawn of life on Earth.
In a proof-of-principle study published last year, the researchers used their approach to record an early, brief and relatively well-studied stage of ribosome assembly from the bacterium E. coli. This involved the transcription, or copying out from its corresponding gene, of a ribosomal RNA, and initial interactions of this RNA strand with a ribosomal protein.
In the new study, the team extended this approach by tracking not only the transcription of a ribosomal RNA but also its real-time folding. The work provided a detailed look at a complex, and until-now mysterious, part of E. coli ribosome assembly — the formation of an entire major component, or domain, of the E. coli ribosome, with assistance from eight protein partners that end up incorporated into the structure.”
The achievement, reported in Cell, reveals in unprecedented detail how strands of ribonucleic acid (RNA), cellular molecules that are inherently sticky and prone to misfold, are “chaperoned” by ribosomal proteins into folding properly and forming one of the main components of ribosomes.
Continue reading “In a first for cell biology, scientists observe ribosome assembly in real time” »
The European patent authorities have rejected an attempt to register an AI as an official inventor.
The possibility’s been a subject of debate for some time, and last summer a group of legal experts decided to force the issue. The group, led by Professor Ryan Abbott of the University of Surrey, submitted designs developed by an AI to the authorities in the US, UK and Europe, and later Germany, Israel, Taiwan and China.
The AI concerned, named Dabus, was created by Stephen Thaler, and is described as a connectionist artificial intelligence.
Solar Foods has developed a sustainable food that’s totally disconnected from agriculture. Now they need to scale it up.
When Solar Foods is producing its novel protein Solein at full-scale production, and using the cheapest source of renewable energy to do so, the start-up believes it ‘could match soy’, CEO Pasi Vainikka tells FoodNavigator.
This special issue of ‘Sophia’ aims to reflect upon future evolutions of religions and their related narratives and imaginaries from a critical and generative understanding of our ancient sources. Bodies are locations of creative power and symbolic proliferation. Cyborgian, transhuman, and posthuman embodiments are going to generate visions of the divine in tune with such an epistemic shift, by addressing questions such as: can God be represented as a cyborg? Could robots and avatars be prophets? Is internet a suitable setting for a posthuman theophany? This special issue articulates within the frame of a relational ontological perspective, according to which the notion of the divine evolves, as much as human and non-human persons do. In this evolutionary scenario, the representation of the divine realm may shift from era to era, adapting to new natural-cultural formations. This special issue argues that the posthuman paradigm shift will be followed by a symbolic turn in religious imaginaries as well.
In a posthuman future, human and non-human beings, plants, and minerals will most likely co-exist with advanced artificial intelligence, sentient robots, and conscious humanoids. As futurist Ray Kurzweil affirms: ‘The introduction of technology is not merely the private affair of one of the Earth’s innumerable species. It is a pivotal event in the history of the planet’ ( 1999, p. 35). Religions will need to re-think their theological approaches in order to allow for different types of subjectivities and embodied entities to partake in the religious quest. Religions themselves are material as well as symbolic networks, actualized through words, prayers, metaphors, rhythms, images, and symbols, among many other expressions. The physical, the virtual, and the symbolic are inextricably intertwined. In the era of the cyborg, God is not only human; in the era of the post-human, humans are not the only prophets.
