Year end inventory: 2018 science magazine heavyweight breakthrough research results

By the end of the year, 2018 is coming to an end, and we will be greeted by a brand new 2019 In 2018, the three famous international magazines cell, nature and Science (CNS) still published a lot of heavyweight research The small and medium-sized editors of this paper collate and share the bright point research published by science in 2018! Photo source: commons.wikipedia.org [1] Science: for 136 years, Johan H gibcus, Kumiko Samejima, Anton goloborodko et al A pathway for mitotic chromosomal formation Science, 18 Jan 2018, DOI: 10.1126/science.aao6135 Since scientists first observed chromosomes under a microscope, a biological mystery has emerged for 136 years, that is, how do chromosomes fold during mitosis? In January 2018, in a research report published in the international journal Science, scientists from Howard Hughes Medical Research Institute and other institutions in the United States said through research that cells roll chromosomes into circular structures, and then wind these circular structures into ladder like spiral structures Most of the time, the chromosomes in our cells are as loose in the nucleus as yarn, the researchers say The scattered chromosome chains look like speckles, but during mitosis, when our cells are ready to divide into two daughter cells and transfer genetic material to these daughter cells, the chromosomes coil up and load about six feet of DNA into tiny packages; the cells can easily transport these concentrated X-shaped masses to their daughter cells Later, the chromosomes are loose again and return to the speckled structure The researchers point out that the new study is expected to unify two conflicting views on chromosome folding during mitosis Chromosomes can be assembled into a series of circular structures, but they can also be in a spiral structure 【2】 Science: a blood test method can simultaneously screen 8 kinds of cancers, Joshua D Cohen, Lu Li, Yuyuan Wang et al Detection and localization of critically responsive cancers with a multi analyze blood test Science, 18 Jan 2018, DOI: 10.1126/science.aar3247, published in the international journal Science in January 2018 In a previous study, researchers from Johns Hopkins University and other research institutions developed a blood test method that can screen eight common types of cancer at a time and help determine where the cancer is located This test method, called cancerseek, is a unique non-invasive multi analyte test method, which can simultaneously evaluate the level of eight kinds of cancer proteins and whether there is cancer gene mutation in circulating DNA in the blood The test aims to screen eight common types of cancer that cause more than 60% of cancer deaths in the United States Five of the eight cancers currently covered by this test have not been screened In this study, the researchers said that the specificity of this test method for cancer is more than 99%; the researchers believe that very high specificity is essential, because false-positive results can allow patients to accept unnecessary invasive follow-up tests to confirm the existence of cancer; this test method tested 812 healthy controls and produced only seven false-positive results 【3】 Science: the first observation of stem cell division in adult brain: Gregor Alexander Pilz, Sara bottes, Marion betizeau et al Live imaging of neurogenesis in the adult mouse hippocampus Science, 09 Feb 2018359 (6376): 658-662, DOI: 10.1126/science.aao5056, published in the international journal Science in February 2018 In a previous research report, researchers from the University of Zurich, Switzerland, successfully tracked a single stem cell and its neurons in a complete adult brain for the first time for algebraic months, which provided new insights into the effective understanding of the generation mechanism of new neurons in the body In this paper, the researchers showed for the first time the process of neural stem cell differentiation and the integration of new neurons in the hippocampus of adult mice They performed in vivo two-photon imaging and genetic markers on neural stem cells to observe stem cell division and track the maturation of new neurons for up to two months By watching these cells work over time, they showed that most stem cells divide only a few rounds before they mature into neurons These results explain why the number of new cells decreases dramatically with age In the past, researchers said, it was technically impossible to track single stem cells in the brain for a while, considering that the hippocampus is located deep in the brain; this study solved the long-standing problems in this field, which is just the beginning of many experiments aimed at understanding how the human brain forms new nerve cells in the whole life process In the future, researchers hope to use neural stem cells for brain repair, such as for the treatment of cognitive aging, Parkinson's disease, Alzheimer's disease or major depression 【4】 Science: activation of lysosomes can rejuvenate aging neural stem cells Dena s Leeman, Katja hebestreit, Tyson ruetz et al Lysome activation clears aggregates and enhances quiet neural stem cell activation during aging Science, 16 Mar 2018359 (6381): 1277-1283, DOI: 10.1126/science.aag3048 In March 2018, in a research report published in the international journal Science, researchers from Stanford University School of medicine in the United States found that in the mouse brain, young stationary neural stem cells can store a large number of protein aggregates in their lysosomes As these neural stem cells age, their ability to clear these protein aggregates gradually declines, and their ability to respond quickly to the signal of "generating new neurons" weakens The researchers found that if the lysosomal function of these cells is restored to normal, their activation ability can be restored Resting or resting neural stem cells are thought to be a truly primitive cell type that just waits for activation, the researchers said But now researchers have found that these cells have more protein aggregates than activated neural stem cells, and these protein aggregates continue to pile up as cells age If these protein aggregates can be removed, the ability of these cells to activate and produce new neurons can be improved If this protein processing function can be restored, it may be very important to 'rejuvenate' the aging static neural stem cells Photo source: en.wikipedia.org [5] Science: high fiber diet can improve the health of patients with type 2 diabetes mellitus Liping Zhao, Feng Zhang, Xiaoying Ding, et al Gutbacteria selectively promoted by dietary fibers allow type 2 diabetes Science, 09 Mar 2018359 (6380): 1151-1156, DOI: 10.1126/science.aao5774 In March 2018, in a research report published in the international journal Science, scientists from China conducted a pioneering study on high fiber diet They found that in patients with type 2 diabetes, the use of a diet rich in multiple fibers can promote a specific group of intestinal microflora Growth leads to better blood sugar control, greater weight loss and better lipid levels, a finding that could soon improve treatment for type 2 diabetes In this paper, the researchers randomly divided type 2 diabetes patients into two groups: control group and treatment group The control group received standard patient education and dietary recommendations The treatment group was given a large number of different types of dietary fiber, while taking a similar diet to provide energy and major nutrients Both groups took the drug acarbose to help control blood sugar After 12 weeks, patients on a high fiber diet experienced a greater reduction in their 3-month average blood sugar levels, faster reductions in their fasting blood sugar levels, and more weight loss Among the 141 strains of enterobacteria identified by next generation sequencing, more fiber intake only promoted the growth of 15 strains of enterobacteria, which may be the key driving factor for improving health Under the promotion of high fiber diet, they can improve the level of butyric acid and acetic acid, and become the dominant strains in the intestine These short chain fatty acids create a mild acidic intestinal environment These acids create a weak acidic gut environment, which reduces the number of harmful bacterial populations and leads to increased insulin production and better blood glucose control This study laid the foundation for the establishment of healthy intestinal flora as a new nutritional method for the prevention and control of type 2 diabetes 【6】 Science: to reveal a new mitochondrial protective mechanism - mitocpr, Hilla weidberg, Angelika amon Mitocpr-a surveillance pathway that protections mitohondria in response to protect import stress Science, 13 APR 2018360 (6385): eaan4146, DOI: 10.1126/science.aan4146 As a kind of organelle, mitochondria provide energy and many necessary metabolites for cells, such as lipids, amino acids, iron sulfur clusters and heme All mitochondrial functions depend on protein input into the organelle, because mitochondrial proteome is almost completely encoded by nuclear genes Although mitochondrial input is extremely important for all mitochondrial functions, up to now, no one has described the response to protein input defects, which protect mitochondria under such stress In April 2018, in a research report published in the international journal Science, scientists from the United States first developed a system in budding yeast to inhibit this process in order to determine how cells respond to mitochondrial protein input defects In this paper, the researchers found that overexpression of proteins that depend on the location of two-component signal sequences in mitochondria can inhibit mitochondrial input and lead to the accumulation of mitochondrial protein precursors Proteinase protection and carbonate extraction assays for mitotic mitochondria revealed that these non input proteins were accumulated on the surface of mitochondria and in the mitochondrial input channels called transposase By developing a system that specifically suppresses mitochondrial protein input, the researchers studied the cell's response to this granulocyte protein input defect Transcriptome analysis was used to identify a gene expression pattern related to multidrug resistance in cells overexpressing proteins with two-component signals The researchers call this response mitochondrion damaging protein input response (mitocpr) Mitocpr is triggered by protein input defects but not by other mitochondrial defects such as mitochondrial respiratory failure, and it is mediated by transcription factor Pdr3 Their analysis further confirmed that mitocpr is essential to protect mitochondria during protein input stress Compared with wild-type cells, cells lacking Pdr3 did not trigger mitocpr during protein input stress, and accumulated higher levels of non input proteins on the surface of such organelles 【7】 Science: the TPO protein needed to maintain bone marrow hematopoietic stem cells is actually produced by liver cells