Scientists in China have taken the lead in some fields, especially in life sciences. The following bio-valley Bian Xiao has compiled some heavy research by China scientists since 20 16 for your reference:
Yan Ning and Gao Fu: Molecular mechanism of cholesterol transport and Ebola virus invasion mediated by NPC 1 protein cells.
(Tsinghua University; China CDC, Microbiology Group of China Academy of Sciences)
Original source:/cell/fulltext/s0092-8674 (16) 30570-0.
On June 2nd, Cell published a research paper entitled "Molecular Mechanism of Cholesterol Transport and Ebola Virus Invasion Mediated by NPC 1 Protein". This research is the latest achievement of the cooperation between Tsinghua University Yan Ning Research Group, China CDC and Academician Gao Fu of China Academy of Sciences. The clear structure of NPC 1 protein was analyzed for the first time in the world, and its working process was initially revealed, which provided basis for intervention and treatment of rare genetic diseases.
NPC 1 is a membrane protein, which consists of 1278 amino acids and contains 13 transmembrane helices. In this paper, the structure of human cholesterol transporter NPC 1 with 4.4 angstrom resolution is reported for the first time in international academic circles. The molecular mechanism of NPC 1 and NPC-2 co-mediating intracellular cholesterol transport was also analyzed and discussed, which provided a molecular basis for understanding the molecular mechanism of NPC 1 mediating Ebola virus invasion.
Cao Xuetao: Finding the "Switch" of Anti-virus Immune Cells-Nature-Immunology
(China Academy of Engineering)
Original source:/ni/journal/v17/n7/full/ni.3464.html.
As the body's self-defense system, the immune system mainly relies on the defense function of immune cells, but how do immune cells recognize foreign viruses and carry out defense work independently?
Cao Xuetao, an academician of China Academy of Engineering, found that DNA methylase Dnmt3a can make natural immune cells highly sensitive to virus infection. Once virus invasion is recognized, it can significantly produce interferon and start the natural immune response against virus. The results of this study were published in the British journal Nature-Immunology.
The researchers chose "epigenetic regulatory molecules" that can regulate DNA methylation to determine gene expression as observation points. After screening, it was found that DNA methylase Dnmt3a can promote natural immune cells to release type I interferon efficiently. The results show that DNA methylation can maintain the high expression of key molecules in antiviral signal transduction pathway, which is fully prepared for natural cells to start antiviral immune response in time and efficiently when viruses invade. This discovery reveals a new epigenetic mechanism of antiviral immune response and provides a new molecular target for the prevention and treatment of viral infectious diseases.
Xie Xiaoliang and Bai Fan: Revealing the Molecular Mechanism of Bacterial Drug Resistance
(Biodynamic Optical Imaging Center, Peking University)
Original source:/molecular-cell/fulltext/s1097-2765 (16) 30048-x.
On April 2 1 day, Molecular Cell, a sub-issue of Cell, a top international academic journal, published the research results of Xie Xiaoliang and Bai Fan, the research group of Biodynamic Optical Imaging Center of Peking University. Using single molecule fluorescence imaging technology and Qualcomm quantitative gene sequencing technology, researchers deeply explored the mechanism of bacterial drug resistance, and revealed the principle that drug-resistant bacteria are still in most physiological activities, but the efflux system is actively working, constantly discharging the drug molecules that continue to enter, adding a safety barrier for the survival of drug-resistant bacteria.
The more active the efflux system is, the lower the concentration of antibiotics in the body, and the bacteria can survive in an environment containing antibiotics. Previous theories believed that the retention bacteria were generally formed by "passive defense strategy", and the latest research results showed that the "active defense strategy" which enhanced the efflux activity and pumped out antibiotics to reduce the intracellular drug concentration also played an important role. This important discovery perfects the existing understanding of the biological mechanism of the formation of retained bacteria.
Wang and Pei: Gastric cells are transformed into hepatopancreatic cells-cell stem cells for the first time.
(Institute of Field Blood Transfusion, Academy of Military Medical Sciences)
Doi: 10. 10 16
A few days ago, Wang and Pei's research team achieved a revolutionary research result. They used the technology of small molecular compounds to directly transform human gastric epithelial cells into endodermal progenitor cells for the first time in the world. Endodermal progenitor cells can be induced to differentiate into mature hepatocytes, pancreatic cells and intestinal epithelial cells, which brings new hope for the future treatment of end-stage liver disease and diabetes with stem cell technology. On July 2 1, the internationally renowned academic journal Cell-Stem Cells published this important achievement online, and three doctors, including Dr. Qin Jinhua, Dr. Wang Shuyong and Dr. Zhang Wencheng, were the first authors of the paper.
This study breaks through the dependence of classical reprogramming on transcription factors, enriches the theoretical system of stem cell regenerative biology, and provides a safe, controllable and effective cell source for mature hepatocytes, pancreatic cells and other functional cells derived from endoderm, which has broad application prospects in personalized regenerative medicine and drug screening. Using this technology, we can carry out personalized tissue culture in medicine, solve the problem of organ transplantation and improve the treatment level of digestive system diseases.
Liu Bing, Tang Fuchou, Yuan Weiping: Single cell scale analysis of hematopoietic stem cells-nature
(Affiliated Hospital of Academy of Military Medical Sciences; Peking University Biooptical Dynamic Imaging Center; Tianjin Blood Hospital of China Academy of Medical Sciences)
Original source:/nature/journal/vaop/ncurrent/full/nature17997.html.
On May 19, Nature published an important breakthrough in the study of the origin of hematopoietic stem cells in the form of a long article, which was jointly completed by China scientists Liu Bing's research group, Tang Fuqiao's research group and Yuan Weiping's research group. Through various research methods such as single cell transcriptome analysis, single cell induced transplantation and tissue-specific gene knockout, the whole development process of mouse hematopoietic stem cells was deeply analyzed at the single cell level for the first time.
Sequencing the single cell transcriptome of five representative cell types during the development of HSC reveals the outstanding characteristics of pre-HSC in transcription activity, metabolic state, arterial gene expression, signal pathway and transcription factor network. Using two kinds of genes specific to vascular endothelial cells and hematopoietic cells to knock out mice, the specific regulatory role of Rictor gene in the development of HSC was clarified. In addition, sequencing data mining and functional experiments confirmed that pre-HSC has heterogeneity of cell cycle state, and some cells proliferate actively. Finally, 98 characteristic genes of pre-HSC were found by comparing and analyzing the sequencing data of more cell populations.
Shao: "Immunity", an HIV neutralizing antibody in adolescence, was isolated from China patients for the first time.
(China Center for Disease Control and Prevention)
doi: 10. 10 16/j . immuni . 20 16 . 03 . 006
In a new study, researchers from China Center for Disease Control and Prevention, Peking University, Nankai University and Scripps Institute (TSRI) described the first immature or "adolescent" antibody found in a class of immune molecules with strong resistance to HIV. The author of this paper is Shao, a biologist and chief expert of AIDS in China Center for Disease Control and Prevention. Related research results were published online in Journal of Immunology on April 5, 20 16.
This research began in 2006, and Zhu and his colleagues were surprised to find that this antibody evolved rapidly from 2006 to 2008, and acquired many characteristics needed to resist HIV. Previous studies suggested that it took 10 to 15 years for the antibody of VRC0 1 to produce useful characteristics, which strongly refuted this point. The researchers also noted that this was the first time that an antibody against VRC0 1 was isolated from an Asian patient. Previous antibodies to VRC0 1 were from African or Caucasian patients. This means that people with different genetic backgrounds may benefit from a vaccine that uses the human body's ability to produce antibodies at the level of VRC0 1.
Liu Guanghui: Inhibition of NRF2 antioxidant pathway leads to premature aging.
(Institute of Biophysics, Chinese Academy of Sciences)
Original source:/cell/fulltext/s0092-8674 (16) 30565-7.
Liu Guanghui Laboratory of Institute of Biophysics, Chinese Academy of Sciences cooperated with Tom Misteli of National Cancer Institute of National Institutes of Health (NIH), and found that the disorder of cell antioxidant pathway mediated by transcription factor NRF2(NF-E2 related factor 2) is the driving force leading to cell aging. In addition, by screening small molecular compounds with the function of activating NRF2 pathway, it is found that an NRF2 agonist Otoprah used to treat fatty liver can delay the aging process of mesenchymal stem cells and improve their in vivo activity. The research results were published in the June 2nd issue of Cell.
Studies have shown that abnormally expressed progerin binds to transcription factor NRF2 and locks it on the nuclear membrane, which makes it unable to activate the expression of downstream antioxidant genes normally, leading to chronic oxidative stress in cells. Inhibition of NRF2 activity in young normal mesenchymal stem cells can simulate various cell defects of premature aging in children, and reactivation of NRF2 in mesenchymal stem cells derived from induced pluripotent stem cells (iPSC) in premature aging children can effectively reverse the phenotype of accelerating aging. These findings not only help to deepen people's understanding of human aging, but also provide new targets and strategies for delaying aging and preventing aging-related diseases.
Zhou Yongsheng: Using adipose-derived stem cells to find a new target for treating bone defect diseases —— Stem Cell Report.
(Peking University College of Stomatology)
doi: 10. 10 16/j . stemcr . 20 16.06 . 0 10？
Recently, the Zhou Yongsheng research team of Peking University Stomatological College published a new research progress in Cell Report. They found that a microRNA can promote bone formation by influencing the signal regulation network of adipose-derived stem cells, which provides a new direction for the treatment of osteoporosis and other diseases with adipose-derived stem cells.
Tissue engineering has become one of the most promising methods in the field of bone regeneration medicine. As a kind of mesenchymal stem cells, human adipose-derived stem cells have attracted more and more attention in the field of tissue engineering. Understanding the molecular regulatory network of adipose-derived stem cells differentiating into bone is an important basis for stem cell therapy.
This study found that MiR-34a was up-regulated during the differentiation of human adipose-derived stem cells (hASC) into bone. Over-expression of MiR-34a in vitro can significantly increase the alkaline phosphatase activity of hASC, and its mineralization ability can also promote the expression of osteogenesis-related genes. The enhancement of osteogenic ability can also be observed in ectopic transplantation after overexpression of MiR-34a by hASC.
China researchers: discover the important MicroRNA that prevents the progress of breast cancer-cancer research.
(Zhongshan University, Guangzhou)
doi: 10. 1 158/0008-5472。 CAN- 15- 1770？
Many studies have shown that the abnormal activation of transcription factor NF-kB in tumor cells is an important driving factor leading to many tumors. Under normal physiological conditions, the expression intensity and duration of NF-kB signal will be strictly regulated at multiple levels, but the mechanism of continuous activation of NF-kB signal pathway in tumors has not been fully clarified.
Recently, researchers from Sun Yat-sen University in Guangzhou published a new research progress in the international academic journal Cancer Research. They found that the silencing of microRNA may be related to the abnormal activation of NF-kB signal in cancer cells.
In this study, the researchers studied the regulation of NF-kB signaling cascade mediated by microRNA in breast cancer cells, and found that the expression of miR-892b in human breast cancer samples was significantly down-regulated, and the expression of this microRNA was related to the survival time of patients.
In vitro and in vivo experiments show that overexpression of miR-892b in breast cancer cells can significantly inhibit the growth, metastasis and angiogenesis of tumor cells, while the absence of miR-892b in cells will enhance the above characteristics. Experiments show that miR-892b can directly inhibit the expression of NF-kB regulatory proteins and NF-kB signaling pathway. Its targets include TRAF2, TAK 1 and TAB3. Therefore, the silencing of miR-892b in breast cancer cells will maintain the activity of NF-kB and lead to the continuous activation of this signaling pathway, thus enhancing the growth and metastasis of tumor cells.
China researcher: Answer how sodium intake affects blood sugar balance-Cell Metabolism.
(China Third Military Medical University)
doi:http://dx . doi . org/ 10. 10 16/j . cmet . 20 16.02 . 0 19？
Researchers from China Third Military Medical University published a new research progress in the international academic journal Cell Metallurgy. They found that sodium intake can regulate blood sugar balance through PPARδ-mediated signal pathway in adipose tissue. This study is of great significance for guiding people to eat healthily and helping diabetic patients to prevent cardiovascular metabolic diseases.
High sodium intake is the main risk factor of hypertension in diabetic patients. Promoting sodium excretion can reduce the risk of cardiovascular metabolic diseases in diabetic patients. However, the relationship between sodium intake and glucose balance is still not well understood.
In this latest study, the researchers reported that high sodium intake can significantly increase urinary sodium excretion in wild-type mice, but this effect was blocked in adipose tissue-specific PPARδ knockout mice and diabetic mice models. At the same time, the researchers found that PPARδ, which activates perirenal fat, can regulate the level of adiponectin in adipose tissue, and then inhibit the function of renal sodium-glucose cotransporter 2(SGLT2), which is the main transporter of renal glucose reabsorption. SGLT2 inhibitor is an important diabetes drug. These results indicate that the process of urinary sodium excretion induced by high sodium salt is regulated by PPARδ in adipose tissue, and the regulation of PPARδ is mediated by adiponectin and realized by regulating the function of SGLT2.
In addition, the researchers also found that in the state of diabetes, the urinary sodium excretion induced by high salt intake was also damaged due to the dysfunction of renal SGLT2. The urinary sodium excretion of type 2 diabetic patients with hyperglycemia is less, which is related to their plasma adiponectin level.