Abstract:Objective: To establish a 3D organoid culture system of mouse fetal liver cell using hyaluronic acid. Method: The fetal liver cells isolated from 12 to 14 days mouse embryos were preliminary screening of 2D liver stem/progenitor cells by Kubota’s Medium (KM) and 3D organoid culture in hyaluronan hydrogel. Result: Fetal liver cells grew as clones in 2D cell culture system. Liver stem/progenitor cell colonies maintained proliferation activity. The albumin and urea levels in supernatant increased significantly, which indicated hepatic functional maturation of the cell colonies in 3D hyaluronic hydrogels. The results of Q-PCR showed that the expression levels of liver stem/progenitor markers, such as AFP, CK19, EpCAM and Prox1, significantly reduced and were close to the expression level in adult mouse liver. Conclusion: In this study, stem-cell derived, functional mouse hepatic organoids in hyaluronan hydrogels was successfully established.

Abstract:Protein ubiquitination is one of the most versatile post-translational modifications, and is widely involved in multiple cellular processes including protein degradation, cellular signaling transduction and DNA damage responses. The eight sites (M1, K6, K11, K27, K29, K33, K48, K63) of ubiquitin help to form individual complex chains by being attached to C-terminus of another ubiquitin molecule. In addition, these different ubiquitin chains play distinct biological functions. However, functions of most ubiquitin chain types are poorly understood, due to the lack of tools that enable ubiquitin linkage-specific detection. Affinity reagents such as ubiquitin linkage-specific antibodies are powerful tools for the studies of the ubiquitin chains. This review focuses on the development and applications of several ubiquitin linkage-specific antibodies, as well as other specific affinity tools, which can be used for identifying of ubiquitin chains such as Affimer and UBD-based fluorescent sensors proteins. This review also briefly introduces the methods of obtaining antigens for the discovery of these ubiquitin linkage-specific antibodies.

Abstract:Brain iron homeostasis plays an important role in maintaining normal brain development and controlling cellular oxidative stress. Accumulating studies have shown that the imbalance of brain iron homeostasis is closely involved in the pathogenesis of Alzheimer’s disease (AD). Here, we reviewed the research progress of the role of iron metabolism in the pathogenesis of AD, particularly focusing on the alterations of several key molecules responsible for cellular iron uptake, storage, release and regulation, and discussed potential therapeutic strategies for AD against the elevated brain iron and altered cellular iron metabolic pathways. This review may contribute to further studies focusing on the role of iron metabolism and related molecules in AD pathogenesis, and provide new insight for the development of AD drugs targeting these molecules.

Abstract:Recognizing the motion of biological entities is crucial for individual survival and social interaction in many species. The properties and influencing factors of biological motion recognition are summarized here, based on the studies in psychophysical experiments, lesions and mental disorder. Then, the main findings in neural mechanism of biological motion recognition are reviewed from the perspective of dorsal-ventral visual pathways, according to the experimental evidences in neuroimaging, lesions and neuro-electrophysiological studies. Finally, some matters and suggestions for future research about neural mechanism of biological motion recognition are put forward.

Abstract:Depression is one of the most complex psychiatric diseases that cause the most serious harm in today"s society. Searching for objective biomarkers of depression has always been the focus and difficulty of psychiatric research and clinical practice. Numerous studies have shown that magnetic resonance imaging (MRI) combined with artificial intelligence technology might be currently the most likely biologic marker to find breakthroughly in mental illness such as depression. However, the current potential objective biomarkers of depression based on psychiatric imaging have not been consistently concluded. From the perspective of combining psychoradiology with artificial intelligence technology represented by machine learning (ML) and deep learning (DL), this paper summarizes and analyses the related studies on depression from three components of the clinical practice including disease diagnosis, prevention and treatment for the first time. We found that a.the brain areas with diagnostic value are mainly concentrated in: precuneus, cingulate gyrus, inferior parietal lobule, insula , thalamus and hippocampus; b.the brain regions with preventive value are mainly concentrated in: precuneus, central posterior gyrus, dorsolateral prefrontal cortex, orbitofrontal cortex, middle temporal gyri; c.brain regions with predictive therapeutic response are mainly concentrated in: precuneus, cingulate gyrus, inferior parietal lobule, middle frontal gyrus, middle occipital gyrus, lingual gyrus. Future research can be improved by enlarging the sample size through multi-center collaboration and data transformation, and at the same time non-imaging data can be applied to data mining, which will help to improve the classification accuracy of artificial intelligence models, and provide scientific evidence and reference for the studies on exploring psychoradiological objective biomarkers for depression and its clinical application.

Abstract:Tiki1 gene, found and named by Professor He Xi"s team from Boston Children"s Hospital, Harvard Medical School, plays a key role in the formation of head in Xenopus. However, as Tiki1 gene is absent in rodents such as mice, it is impossible to use mice or rat to study its role in mammals. In this study, we generated Tiki1 gene modified pigs using CRISPR/Cas9 system combined with somatic cell cloning technology to study the role of Tiki1 gene in pig development. Aligned the human Tiki1 mRNA sequence provided by professor He Xi"s team with the pig genome database, we selected two target sites (g1 and g2) with the top 2 highest sequence identity at the predicted pig Tiki1 gene locus. The sgrRNA plasmid was constructed to transfect porcine fetal fibroblasts, and 52 single cell clones were screened and sequenced. We finally selected 5 single-cell clones with biallelic knockout mutations at target site g1 and 3 single-cell clones with biallelic knockout mutations at target site g2 as nuclear donors for constructing Tiki1 knockout pigs. A total of 720 recombinant embryos were constructed and transferred into three surrogate sows and one of them was successfully pregnant monitored by B ultrasound. A total of 13 cloned piglets (ten living piglets and 3 dead piglets ) were produced, and 12 of them were biallelic knockout mutations at Tiki1 locus. Both the living and dead Tiki1 gene knockout cloned piglets were developed normally and the living piglets have survived healthy till now. The results indicate that the role of Tiki1 gene on early development of pigs is different from that of frogs. The specific role of Tiki1 gene in the early development of pigs needs to be further investigated.

Abstract:Invariant natural killer T (iNKT) cells are a subset of innate-like T cells, which play important regulatory roles in multiple diseases including infection, tumor and metabolic diseases. Revealing the cellular and molecular mechanisms that regulate the development, differentiation and function of iNKT cells is of great significance to elucidate the relationship between iNKT cells and diseases and to seek possible therapeutic approaches. Etoposide-induced protein 2.4 (Ei24) is an autophagy-associated protein which involved in the regulation of cell growth and apoptosis. However, whether Ei24 could regulate iNKT cell differentiation and functions remains unclear. Here, using Cre/loxP system to specifically delete Ei24 in T cells, we found that Ei24 was required for terminal maturation of iNKT cells in thymus, liver and spleen. iNKT1 and iNKT17, but not iNKT2 cells, were affected by Ei24 deficiency. Furthermore, we found that the production of IFN-γ, but not IL-4, was impaired in Ei24 deficient iNKT cells when lipid antigen α-GC was injected in vivo. These results demonstrate that Ei24 is required for the development and function of iNKT cells.

Abstract:Western blot (WB) is widely used to investigate the expression profiling for target proteins，which depends on the specific binding with antibodies and it is a fundamental technique in basic and application field of life science. However, traditional WB technique involves many manual steps, it is difficult to set up standard operational protocols. In most of the cases, it is used only within same WB analysis for the abundance investigation of target proteins qualitatively or relative quantitatively, while problematic to carry out comparison among different laboratories. In the current paper, after a summarized historical review of WB development, the concept of advance version of WB (WB 2.0) was proposed. The key components for the design and practical steps including digitalization, standardization, automation, micro-quantification, high through-put, reference-based normalization and database establishment were presented. In perspective, the application of WB 2.0 will activate the establishment of a public accessible protein expression database, which will be another supporting platform for life science succeeding the recognized genome and transcriptome databases.

Abstract:组蛋白甲基化修饰与基因的转录调控密切相关，其中果蝇的Ash1以及哺乳动物的同源蛋白Ash1L是催化组蛋白H3上36位赖氨酸进行单甲基化和双甲基化的甲基转移酶. 由于存在一个自抑制环区阻挡了底物的结合位点，Ash1/Ash1L本身的组蛋白甲基转移酶活性是很低的. 但与Mrg15结合后，Ash1/Ash1L从原来的自抑制态转变为活化态. 最近，Ash1L与Mrg15结合后复合物的晶体结构被成功解析出来，使之可以揭示Ash1L与Mrg15之间的特异相互作用以及Mrg15激活Ash1L的机理. 我们通过比较Ash1L/Mrg15复合物的两个晶体结构来讨论Ash1L分子中的天然无序区域在其活化过程中所起的重要调控作用.

Abstract: