To date, the most complete map of human cells has been released; plants have been planted on lunar soil for the first time | Global scientific news

The most complete map of human cells has been released so far.

Today, Science magazine published four papers simultaneously, publishing the most comprehensive pan-tissue human single cell map constructed by scientists of the International Union of Human Cell Atlas. This map, which contains 33 human tissues, more than 1 million cells and more than 500 cell types, provides extremely important insights into common and rare diseases, vaccine development, anti-tumor immunity and regenerative medicine.

In the first study, the researchers collected nearly 500000 living cells from organs donated by multiple subjects and described more than 500000 cell types in 24 organs and tissues, including epithelial cells, endothelial cells, stromal cells and immune cells, through single cell RNA sequencing (scRNA-seq), creating the whiteboard Homo sapiens (Tabula Sapiens) data set. In the second study, researchers at the Baird Institute in the United States used optimized mononuclear RNA sequencing (snRNA-seq) to analyze frozen samples from 8 healthy human organs from 16 donors, and obtained cross-tissue maps of more than 200000 cells and some rare cell types. In addition, they used machine learning algorithms to systematically associate these cells with 6000 single gene diseases and 2000 complex genetic diseases, and found the cell types affected by pathogenic genes and disease traits. In the third study, scientists from the Wellcome Sanger Institute and the University of Cambridge analyzed immune cells in 16 tissues from 12 adult organ donors by snRNA-seq, constructed a cell map containing 330000 immune cells, and identified about 100 different types of immune cells. In the final study, the scientists collected eight kinds of human tissues during pregnancy, created a cell map of the immune system before birth, and determined the specific location of these cells in the developmental tissue. It has been found that B cell precursors are present in all developmental organs in the early stage of development, and some immune cell types that are not found in adults are identified.

? Planetary science?

Plant plants in the lunar soil for the first time

Recently, a study published in the journal Communication Biology has cultivated plants on lunar soil for the first time and explored their growth patterns. A total of 12 grams of lunar soil samples collected by Apollo 11, 12 and 17 were used in the experiment. In order to make full use of valuable lunar soil samples, the researchers used cell culture plates as containers, with about one gram of lunar soil in each hole.

In addition to lunar soil samples, lunar soil simulations, Martian soil simulations and earth soils were used as comparisons. The researchers then moisturized the soil with nutrients and sowed Arabidopsis seeds. Because the gene sequencing of Arabidopsis thaliana is complete, researchers can track the effects of lunar soil on plant gene expression. It was found that almost all Arabidopsis thaliana germinated in lunar soil, but there were some differences in Arabidopsis thaliana growth, plant size or plant size compared with the other three control groups. When further analyzing the gene expression of Arabidopsis thaliana, the researchers found that Arabidopsis thaliana growing in lunar soil responded to stress, indicating that plants regard lunar soil as a source of stress. The researchers also found that plants grow better in less mature lunar soils than mature lunar soils, which undergo long-term space weathering.

? Virology?

18000 new cases of fever in North Korea yesterday

A total of 187800 people are receiving quarantine treatment after 18000 new fever cases and six deaths (including one confirmed case by COVID-19) were reported across the country on Monday, according to the Korean Central News Agency. Reported that since the end of April, fever of unknown causes has spread throughout North Korea, causing more than 350000 cases of fever in a short period of time, of which 162200 have been cured. (CCTV News)

? Physics?

Preparation of Quantum Magnetic Sensor from Diamond

Diamonds can not only be used as jewelry ornaments, but also a new type of quantum material with considerable research value. Nitrogen vacancy defect, NV color center, is a common point defect in diamond crystal structure, which is formed by nitrogen atom replacing carbon atom and adjacent hole. Precise magnetic measurement can be carried out by using its quantum paramagnetic resonance effect and fluorescence radiation characteristics in magnetic field. Recently, the State key Laboratory of Sensing Technology of Shanghai Institute of Microsystems and Information Technology of the Chinese Academy of Sciences has prepared a miniature optoelectronic integrated diamond quantum magnetic sensor based on nitrogen vacancy color center. The related research is published in KuaiBao of Applied Physics.

Based on the wafer-level MEMS platform and the standard micro-nano machining technology, the research team fabricated the diamond chip, which is the core of the diamond quantum magnetic sensor. The microwave radiation structure is integrated in the chip, and the in-situ microwave quantum state manipulation is realized. The diamond chip is coupled with an optical fiber module with a gradient refractive index lens, which realizes the working mode of "light in and out", reduces the size of the probe and realizes the high integration of the diamond magnetometer probe. The study further shows that the dual-frequency resonance technology can be used to measure the magnetic field and temperature field simultaneously, which not only improves the signal-to-noise ratio of magnetic field measurement through temperature drift suppression, but also ensures the temperature stability of the sensor. This study provides the possibility to establish a wearable sensor array with high consistency and high sensitivity. (Chinese Academy of Sciences)

? Biology?

The Theory of Life Origin of RNA- protein Hybridization

The "RNA World" hypothesis holds that life may exist in the form of complex primitive RNA chains that can replicate themselves and catalyze them. But these RNA need to evolve the ability to make proteins and ribosomes and eventually transfer the genetic information they carry to a more stable DNA. In a study published in Nature on May 11, scientists found that some unconventional bases in RNA can bind to amino acids, prompting them to bind to form a peptide chain of up to 15 amino acids.

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In the study, the researchers were inspired by ribosomes constructed by RNA and proteins to construct two paired RNA single strands. One of the chains is a "donor chain", which contains an unconventional base T6A, which binds to amino acids, and an unconventional base mnm5U is carried at the end of the "recipient chain". They found that when the two strands combine, the amino acids on T6A detach and bind to mnm5U with only a little heat. This process can be repeated, and the amino acids from the next "donor chain" will form covalent bonds with the amino acids on the mnm5U, resulting in a peptide chain containing a total of 15 amino acids, which can promote the more stable binding of the RNA chain. Studies have shown that the formation of peptides and RNA may have a synergistic effect: RNA may contribute to the formation of peptides, while peptides may contribute to the formation of more stable and longer RNA chains.

? Environment?

Existing models overestimate the ability of forests to absorb carbon.

Through photosynthesis, forests capture and fix carbon in the atmosphere in the form of woody biomass and soil carbon. Scientists have long believed that photosynthesis and plant growth are limited by the amount of carbon in the atmosphere-the more carbon there is, the more plants grow and the more space they have to store carbon. However, more and more studies have shown that forest carbon storage is also sensitive to other factors, including temp