Single-cell landscape of the ecosystem in early-relapse hepatocellular carcinoma

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The 30-Base-Pair Deletion in Chinese Variants of the Epstein-Barr Virus LMP1 Gene Is Not the Major Effector of Functional Differences between Variant LMP1 Genes in Human Lymphocytes

One group of sequence variants of Epstein-Barr virus is characterized by a 10-amino-acid deletion within the CTAR-2 functional domain of the latent membrane protein, LMP1. A role for this deletion in enhancing the tumorigenicity of the viral oncogene in rodent fibroblasts was recently demonstrated. We examined the effect of this deletion upon LMP1 function in four human lymphoid cell lines by using three natural variants of LMP1: the prototype B95.8 gene and the CAO and AG876 genes, both of which have codons 343 to 352 of the B95.8-LMP1 deleted. These experiments revealed that LMP1-mediated upregulation of CD40 and CD54 was markedly impaired (by 60 to 90%) with CAO-LMP1 compared with B95.8-LMP1. In contrast, the function of AG876-LMP1 was indistinguishable from that of B95.8-LMP1 in two lines and was only slightly impaired in the other two lines. Activation of NF-κB by CAO-LMP1 was not impaired in any of the lines; rather, activation of an NF-κB reporter by CAO-LMP1 was consistently about twofold greater than the activation with B95.8- or AG876-LMP1. Therefore, while the CAO-LMP1 is functionally distinct from the prototype B95.8-LMP1 in human lymphocytes, the 10-amino-acid deletion appears not to be directly responsible. This conclusion was confirmed by using a B95.8-LMP1 mutant with codons 343 to 352 deleted and chimerae of CAO- and B95.8-LMP1 in which the CTAR-2 domains of these genes were exchanged. Sequences outside the CTAR-2 domain were implicated in the distinct functional characteristics of CAO-LMP1 in human lymphoid cells.     

A New Electrolyte Formulation for Securing High Temperature Cycling and Storage Performances of Na‐Ion Batteries

The Na‐ion battery is recognized as a possible alternative to the Li‐ion battery for applications where power and cost override energy density performance. However, the increasing instability of their electrolyte with temperature is still problematic. Thus, a central question remains how to design Na‐based electrolytes. Here, the discovery of a Na‐based electrolyte formulation is reported which enlists four additives (vinylene carbonate, succinonitrile, 1,3‐propane sultone, and sodium difluoro(oxalate)borate) in proper quantities that synergistically combine their positive attributes to enable a stable solid electrolyte interphase at both negative and positive electrodes surface at 55 °C. Moreover, the role of each additive that consists in producing specific NaF coatings, thin elastomers, sulfate‐based deposits, and so on via combined impedance and X‐ray photoelectron spectroscopy is rationalized. It is demonstrated that empirical electrolyte design rules previously established for Li‐ion technology together with theoretical guidance is vital in the quest for better Na‐based electrolytes that can be extended to other chemistries. Overall, this finding, which is implemented to 18 650 cells, widens the route to the rapid development of the Na‐ion technology based on Na₃V₂(PO₄)₂F₃/C chemistry.     

Solution structure of the N‐terminal domain of DC‐UbP/UBTD2 and its interaction with ubiquitin

DC‐UbP/UBTD2 is a ubiquitin (Ub) domain‐containing protein first identified from dendritic cells, and is implicated in ubiquitination pathway. The solution structure and backbone dynamics of the C‐terminal Ub‐like (UbL) domain were elucidated in our previous work. To further understand the biological function of DC‐UbP, we then solved the solution structure of the N‐terminal domain of DC‐UbP (DC‐UbP_N) and studied its Ub binding properties by NMR techniques. The results show that DC‐UbP_N holds a novel structural fold and acts as a Ub‐binding domain (UBD) but with low affinity. This implies that the DC‐UbP protein, composing of a combination of both UbL and UBD domains, might play an important role in regulating protein ubiquitination and delivery of ubiquitinated substrates in eukaryotic cells.     

N-糖蛋白去糖基化酶（PNGase）的研究进展

N-糖蛋白去糖基化酶（PNGase）是一种广泛存在于真菌、植物、哺乳动物中的去糖基化酶，可以水解N-糖蛋白或 N-糖肽上天冬酰胺与寡糖链连接的化学键，并释放出完整的N-寡糖。PNGase在生物体内参与蛋白质降解、器官发育、个体生长等过程。人PNGase基因功能缺陷会导致先天性去糖基化障碍，小鼠PNGase缺陷会导致胚胎致死性，线虫PNGase缺陷使其寿命下降。本文对PNGase在不同物种的分布、蛋白质结构、酶学功能及生物学功能进行阐述，为PNGase的生理病理功能及致病机制的基础研究提供思路，为PNGase作为糖生物学工具酶或药物开发的创新应用研究奠定基础。     

Cytosolic HMGB1 Mediates Autophagy Activation in an Emulsified Isoflurane Anesthesia Cell Model

Neurochemical Research - Inhalation anesthetic isoflurane may cause an increased risk of cognitive impairment. Previous studies have indicated that this cognitive decline is associated with...