Environment-based object values learned by local network in the striatum tail
Value and reward are known to be encoded in the part of the brain called the basal ganglia. Research has identified the specific neuronal circuits underlying environment-based value learning.
Obtaining valuables is one of the most important actions for the survival of animals, including humans. And even if they are the same, their value to animals changes depending on the environment and circumstances in which they are placed. Animals make good judgments about their value based on experience and learning. So what is the mechanism by which we learn the value of things?
→ Published in PNAS January 26, 2021 118 (4) e2013623118
Environment-based object values learned by local network in the striatum tail
In skeletal muscle, quiescent satellite cells maintain low levels of protein synthesis, mediated in part through the phosphorylation of eIF2α (P-eIF2α). Paradoxically, P-eIF2α also increases the translation of specific mRNAs, which is mediated by P-eIF2α dependent read through of inhibitory upstream open reading frames (uORFs). Here, we ask whether P-eIF2α dependent mRNA translation enables expansion of satellite cells. We demonstrate that uORFs in the 5’UTR of mRNA for the mitotic spindle stability gene Tacc3 direct P-eIF2α dependent translation. Satellite cells deficient for TACC3 exhibit defects in expansion, self-renewal and regeneration of skeletal muscle.
→ Tsukuba Journal - University of Tsukuba (Japanese language)
Research on astronaut health and model organisms have revealed six features of spaceflight biology that guide current understanding of fundamental molecular changes that occur during space travel.
→ Cell – Volume 183, Issue 5, 25 November 2020, Pages 1162-1184
In vitro data and molecular dynamics simulations suggest that KS-58 enters cells and blocks intracellular Ras–effector protein interactions. KS-58 selectively binds to K-Ras(G12D) and suppresses the in vitro proliferation of the human lung cancer cell line A427 and the human pancreatic cancer cell line PANC-1, both of which express K-Ras(G12D). Moreover, KS-58 exhibits anti-cancer activity when given as an intravenous injection to mice with subcutaneous or orthotropic PANC-1 cell xenografts. The anti-cancer activity is further improved by combination with gemcitabine.
A New Era for Space Life Science: International Standards for Space Omics Processing
(Published Nov 26, 2020)
TMRC Genomics Division members have been involved in the formation of ISSOP (International Standards for Space Omics Processing).
Scientists across the world are conducting space omics studies to develop countermeasures for safe and effective crewed space missions. However, optimal extraction of scientific insight from such data is contingent on improved standardization.
ISSOP has been founded as an international consortium of scientists who aim to enhance guidelines between space biologists globally.
This paper informs scientists and data scientists from many fields about the challenges and future avenues of space omics and can serve as an introductory reference for new members in the space biology discipline.
→ A New Era for Space Life Science: International Standards for Space Omics Processing
→ Press Release - University of Tsukuba Website (in Japanese language)
→ Research Outline PDF (In Japanese language)
(Published Nov 11, 2020)
Professor Masayuki Matsumoto, TMRC University of Tsukuba, Faculty of Medicine
“Every day of our lives, we make many different decisions. In many cases, we are faced with choosing which of several options would be most rewarding for us. What kind of brain mechanisms might be responsible for the logical decision-making that helps us choose more rewarding behaviors? The key to answering this question is a substance called dopamine, and the neurons that produce it, called dopamine neurons. Prof. Matsumoto is studying the functions of dopamine neurons with the aim of uncovering what role they play in decision-making.”
(Published Nov 11, 2020)
The intestinal environment, including the gut flora, has been shown to interact with brain function.
In this study, the relationship between the intestinal flora and sleep was investigated using mice in which the intestinal flora was removed by chronic antibiotic administration. A metabolome analysis of the contents of the cecum determined that the state of intestinal metabolism in “intestinal flora-removed” mice showed significant changes in the metabolic pathways of amino acids involved in neurotransmitter synthesis compared to normal mice. In particular, vitamin B6 was significantly reduced and serotonin, which regulates nerve function, was depleted.
On the other hand, a significant increase in glycine and gamma-aminobutyric acid (GABA), which suppress the activity of nerve cells, was observed.
When sleep was analyzed using EEG and EMG, “intestinal flora-removed” mice had decreased sleep in the light period (sleep period) and increased sleep in the dark period (active period). The day and night, sleep / wakefulness pattern was weakened. It was also found that theta waves, which are the characteristic brain waves components of REM sleep with cerebral cortex activity, were reduced. These findings suggest that removal of the gut flora may reduce sleep quality.
It is expected that further research may allow new methodologies for promoting improved health through a deeper understanding of the interaction between the intestinal environment and brain function (gut-brain axis) and eating habits.
Limited rejuvenation of aged hematopoietic stem cells in young bone marrow niche
Key Point
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Generation of a p16ʰⁱᵍʰ Reporter Mouse and Its Use to Characterize and Target p16ʰⁱᵍʰ Cells In Vivo
(Available online Sept 18th, 2020)
Key Points
• p16high cells are detectable in all tissues, are enriched with age, and do not proliferate.
• p16high cells exhibit heterogenous senescence-associated phenotypes.
• Elimination of p16high cells ameliorates steatosis and inflammation in a NASH model.
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