Background: EPB41L1 gene (erythrocyte membrane protein band 4.1 like 1) encodes the protein 4.1N, a member of 4.1 family, playing a vital role in cell adhesion and migration, which is associated with the malignant progression of various human cancers. However, the expression and prognostic significance of EPB41L1 in kidney renal clear cell carcinoma (KIRC) remain to be investigated. Methods: In this study, we collected the mRNA expression of EPB41L1 in KIRC through the Oncomine platform, and used the HPA database to perform the pathological tissue immunohistochemistry in patients. Then, the sub-groups and prognosis of KIRC were performed by UALCAN and GEPIA web-tool, respectively. Further, the mutation of EPB41L1 in KIRC was analyzed by c-Bioportal. The co-expression genes of EPB41L1 in KIRC were displayed from the LinkedOmics database, and function enrichment analysis was used by LinkFinder module in LinkedOmics. The function of EPB41L1 in cell adhesion and migration was confirmed by wound healing assay using 786-O cells in vitro. Co-expression gene network was constructed through the STRING database, and the MCODE plug-in of which was used to build the gene modules, both of them was visualized by Cytoscape software. Finally, the top modular genes in the same patient cohort were constructed through data mining in TCGA by using the UCSC Xena browser. Results: The results indicated that EPB41L1 was down-expressed in KIRC, leading to a poor prognosis. Moreover, there is a mutation in the FERM domain of EPB41L1, but it has no significant effect on the prognosis of KIRC. The co-expressed genes of EPB41L1 were associated with cell adhesion and confirmed in vitro. Further analysis suggested that EPB41L1 and amyloid beta precursor protein (APP) were coordinated to regulated cancer cell adhesion, thereby increasing the incidence of cancer cell metastasis and tumor invasion. Conclusions: In summary, EPB41L1 is constantly down-expressed in KIRC tissues, resulting a poor prognosis. Therefore, we suggest that it can be an effective biomarker for the diagnosis of KIRC.

The dynamic balance of DNA methylation and demethylation is required for erythropoiesis. Our previous transcriptomic analyses revealed that DNA methyltransferase 1 (DNMT1) is abundantly expressed in erythroid cells at all developmental stages. However, the role and molecular mechanisms of DNMT1 in human erythropoiesis remain unknown. Here we found that DNMT1 deficiency led to cell cycle arrest of erythroid progenitors which was partially rescued by treatment with a p21 inhibitor UC2288. Mechanically, this is due to decreased DNA methylation of p21 promoter, leading to upregulation of p21 expression. In contrast, DNMT1 deficiency led to increased apoptosis during terminal stage by inducing endoplasmic reticulum (ER) stress in a p21 independent manner. ER stress was attributed to the upregulation of RPL15 expression due to the decreased DNA methylation at RPL15 promoter. The upregulated RPL15 expression subsequently caused a significant upregulation of core ribosomal proteins (RPs) and thus ultimately activated all branches of unfolded protein response (UPR) leading to the excessive ER stress, suggesting a role of DNMT1 in maintaining protein homeostasis during terminal erythroid differentiation. Furthermore, the increased apoptosis was significantly rescued by the treatment of ER stress inhibitor TUDCA. Our findings demonstrate the stage-specific role of DNMT1 in regulating human erythropoiesis and provide new insights into regulation of human erythropoiesis.

An in situ labelling strategy was proposed to produce quantum dot-labelled respiratory syncytial viruses (RSVs) by incorporating the biotinylated membrane protein of the host cells into mature virions, followed by conjugation with streptavidin modified quantum dots (SA-QDs), which has the advantages such as convenience, efficiency and minor influence on viral infectivity and thus could be successfully applied to track the early stage of virus entry.

Acute liver injury (ALI) is a common clinical disease caused by sepsis, metabolic syndrome, hepatitis virus. Macrophage plays an important role in the development of ALI, which is characterized by polarization and inflammatory regulation. The polarization process of macrophages is related to membrane binding proteins and adaptors. Protein 4.1R acts as an adaptor, linking membrane proteins to the cytoskeleton, and is involved in cell activation and cytokine secretion. However, whether protein 4.1R is involved in regulating macrophage polarization and inflammation-induced liver injury remains unknown. In this study, protein 4.1R is identified with the special effect on macrophage M1 polarization. And it is further demonstrated that protein 4.1R deficiency significantly enhance glycolytic metabolism. Mechanistically, the regulation of protein 4.1R on pyruvate kinase M2 (PKM2) plays a key role in glycolysis metabolism. In addition, we found that protein 4.1R directly interacts with toll-like receptor 4 (TLR4), inhibits the activation of the AKT/HIF-1α signaling pathway. In conclusion, protein 4.1R targets HIF-1α mediated glycolysis regulates M1 macrophage polarization, indicating that protein 4.1R is a candidate for regulating macrophage mediated inflammatory response. In conclusion, we have revealed a novel function of protein 4.1R in macrophage polarization and ALI, providing important insights into the metabolic reprogramming, which is important for ALI therapy. We have revealed a novel function of protein 4.1R in macrophage polarization and ALI, providing important insights into the metabolic reprogramming, which is important for ALI therapy.