The essence of the March 5, 2021 issue of Science

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Science。

1.

，。Daniel Candinas，“，，。”，，，。CandinasJoel Zindel。202135Science，“Primordial GATA6 macrophages function as extravascular platelets in sterile injury”。

2.

In this new study, Kuanal Bhutani and his colleagues performed single-cell RNA sequencing on sperm from mice, cattle, and humans, and found that a large group of mammalian genes are combined on the cytoplasmic bridge that connects neighboring sperm.
Not fully shared.
Some of these genes are called "genoinformative markers (GIM)" by these authors, which can be used as selfish genetic factors to spread alleles unevenly in the population.
This discovery reveals the mechanism of natural selection at the sperm level.

3.
Science: using bispecific antibodies to target cancer
doi:10.

In a new study, researchers from Johns Hopkins University School of Medicine in the United States tried to develop an immunotherapy method to target the protein encoded by the mutated TP53 gene.
p53 is an intracellular protein, mainly located in the nucleus, so traditional antibody-based therapies cannot be achieved.
However, the protein is degraded by the proteasome into peptides, some of which can be presented on the cell surface by the human leukocyte antigen (HLA).
This, in principle, allows a properly designed protein to recognize peptide fragments of intracellular proteins when it binds to HLA on the cell surface.

4.
Science: Heavy! Scientists are expected to develop new therapies for blood diseases that endanger human lives !
doi:10.

Yuanbin Song, MD, said that human red blood cell diseases such as thalassemia and sickle cell disease affect the health of approximately 5% of the world’s population.
Our findings highlight the complex relationship between red blood cells and liver in this newly developed model.
Unique potential in disease, such as malaria, etc.

5.
Interpretation of Science papers! Nematodes without eyes guide foraging by distinguishing colors
doi:10.

H.
Robert Horvitz, a professor of biology at the Massachusetts Institute of Technology and co-author of the paper, said, “For me, a tiny nematode--with neither eyes nor molecular machines that detect colors--can recognize And avoiding a toxic bacteria, which is partly based on its blue color.
One of the joys of being a biologist is to have the opportunity to discover things in nature that no one has ever imagined.
"

6.
bioon.
com/article/6785142.
html" target="_blank">Science: New research has identified a variety of cardiac progenitor cell populations in the mouse embryonic heart region
doi:10.

The heart of vertebrates is made up of different types of cells, which are all essential for normal heart function.
In mice, the earliest mesoderm progenitor cells of cardiomyocytes are formed during gastrulation, migrate from the primitive streak to the rostral side, form a heart crescent, and begin to contract.
The heart crescent shape is then reshaped to form a linear heart tube.
There are at least two different sets of mesodermal cardiac progenitor cells: the first heart field (FHF) and the second heart field (SHF).
These two groups of mesodermal cardiac progenitor cells are different according to the early embryo.
However, the marker genes expressed in the overlapping regions are roughly determined.
Cells from outside these heart-producing areas also help the heart.
One such structure, the proepicardium, produces the epicardium, which is the outermost layer of cells in the vertebrate heart.
The epicardium provides important paracrine signals and can also produce a variety of heart cell types, including cardiomyocytes, vascular smooth muscle cells, and fibroblasts.

Scientists currently have limited understanding of when and how different heart cell types are produced during early development.
Single-cell transcriptomics provides a powerful method to characterize the various cell types of the embryonic heart and generate hypotheses about their origin and fate.
Therefore, in a new study, researchers from the University of Oxford, Cambridge University, and the Helmholtz Munich Center in Germany combined single-cell RNA sequencing with high-resolution volume imaging and time-lapse microscopy to achieve single-cell resolution.
To accurately characterize the cells of the mouse embryonic heart.
This powerful combination method provides a unified transcriptional and anatomical definition of cardiac progenitor cell types and their differentiation trajectories into cardiomyocytes.
The relevant research results were published in the Science Journal on March 5, 2021, with the title of the paper "Characterization of a common progenitor pool of the epicardium and myocardium".

7.
Science: Antibiotics with redox activity can increase the bioavailability of phosphorus
doi:10.
1126/science.
abd1515

Bacteria secrete a series of chemically reactive small molecules that provide multiple functions in different environments.
Phenazine molecules are generally considered antibiotics, but they can also participate in environmental redox reactions, especially reactions with iron.
McRose and Newman found that when exogenous additions or bacteria are made in situ, phenazine molecules can liberate phosphorus (P) from the surface of minerals in the form of phosphate, and the production of these molecules is controlled by signals in response to phosphorus limitation.
Regulation of pathways.
Bacterial strains that cannot produce these molecules grow more slowly under phosphorus limitation, but can be rescued by adding exogenous phenazine molecules.
These authors speculate that the reductive dissolution of iron oxides has the benefit of releasing phosphorus, which may be one of the mechanisms by which microorganisms in certain environments obtain phosphorus.

8.
Science: The warmer months of autumn lead to a decline in the number of butterflies
doi:10.
1126/science.
abe5585

Many recent studies have shown that the number of insects has declined sharply in the past few decades.
Butterflies are no exception.
Forister et al.
used three different data sets collected by experts and community scientists and found that the number of butterflies has declined in the past 40 years.
Although the drivers of the decline are complex, these authors found that climate change--especially the warm months of autumn--explained a large part, even though summer warming actually led to the increase.
This study shows that the effects of climate change may be hidden and its effects are unexpected.

9.
Science: Structurally reveal the regulation mechanism of cholesterol levels in cells
doi:10.
1126/science.
abb2224

Cholesterol levels in cells are controlled by the sterol regulatory element binding protein (SREBP) pathway.
When there is enough cholesterol in the cell, the transcription factor that regulates cholesterol metabolism is sealed on the endoplasmic reticulum membrane, but when cholesterol is depleted, this transcription factor is released and activates the genes involved in cholesterol synthesis and absorption.
expression.
Yan et al.
determined the structure of the central complex containing Scap and Insig-2 proteins in human SREBP.
These two membrane chimeric proteins undergo a 25-hydroxycholesterol (25HC) dependent association and must be dissociated to activate this pathway.
This structure shows that 25HC is sandwiched between Scap and Insig-2 to promote their union.
The catastrophe analysis is consistent with this structural model.

10.
Science: Parallel molecular mechanism of enzyme temperature adaptation
doi:10.
1126/science.
aay2784

Enzymes maintain a delicate balance between features that enhance chemical reactivity and features that help stabilize structures.
Both of these characteristics are important and can be irrelevant or adversarial.
Pinney et al.
combined the rich experimental work of thermophilic and mesophilic variants of ketosteroid isomerase (KSI) with bioinformatics data from different bacterial enzymes, revealing the molecular determination of the enzyme's thermal adaptability factor.
For KSI, they observed a trade-off between activity and thermal stability, which ultimately boiled down to a single active site residue.
Using a larger data set, they identified patterns that favor single amino acid substitutions at higher temperatures, and also considered how a network of stable interactions was created.
(Bioon.
com)