The RNA transport factor PHAX is required for proper histone H2AX expression and DNA damage response

Phosphorylated Adapter RNA Export Protein Is Methylated at Lys 381 by an Methyltransferase-like 21C (METTL21C)

Methyltransferase-like 21C (METTL21C) is a member of the non-histone methyltransferase superfamily, which mainly mediates the methylation of lysine (Lys) residues. The main types of modification are Lys dimethylation and trimethylation. However, at present, most of the studies on METTL21C are focused on humans and mice, and there are few reports on poultry. Therefore, chicken embryo fibroblasts (DF-1) were selected as the object of study. To explore the function of chicken METTL21C (chMETTL21C) in the proliferation of DF-1 cells, flow cytometry and qPCR were used to detect the function of chicken METTL21C in the proliferation of DF-1 cells. The results showed that overexpression of METTL21C blocked the cell cycle in the G1max S phase, thus inhibiting cell proliferation. In addition, based on proteomic analysis, stable overexpression of METTL21C may inhibit the proliferation of DF-1 cells by mediating lysine trimethylation of proliferation-related proteins phosphorylated adapter RNA export protein (PHAX), nucleoside diphosphate kinases (NDPKs), eukaryotic transcription extension factor (eukaryotic translation elongation factor 1A,e EF1A), and inversin (Invs). Through immunoprecipitation (co-IP) and liquid chromatography-mass spectrometry (LC-MS/MS) analysis, METTL21C-mediated PHAX Lys-381 methylation was confirmed to be involved in the regulation of DF-1 cell proliferation. The results of this study provide a reference for analyzing the methylation function of METTL21C and the mechanism of regulating the growth and development of chicken cells.

Arsenic resistance protein 2 and microRNA biogenesis: Biological implications in cancer development

Arsenic resistance protein 2 (Ars2) is a nuclear protein that plays a critical role in the regulation of microRNA (miRNA) biogenesis. Ars2 is required for cell proliferation and for the early stages of mammalian development through a possible effect on miRNA processing. Increasing evidence reveal that Ars2 is highly expressed in proliferating cancer cells, suggesting that Ars2 may be a potential therapeutic target for cancer. Therefore, development of the novel Ars2 inhibitors could represent the novel therapeutic strategies for treatment of cancer. In this review, we briefly discuss the mechanisms by which Ars2 regulates miRNA biogenesis and its impact on cell proliferation and cancer development. Particularly, we mainly discuss the role of Ars2 in the regulation of cancer development and highlight pharmacological targeting of Ars2 as a promising cancer therapeutic strategy.

The regulatory roles of the E3 ubiquitin ligase NEDD4 family in DNA damage response

E3 ubiquitin ligases, an important part of ubiquitin proteasome system, catalyze the covalent binding of ubiquitin to target substrates, which plays a role in protein ubiquitination and regulates different biological process. DNA damage response (DDR) is induced in response to DNA damage to maintain genome integrity and stability, and this process has crucial significance to a series of cell activities such as differentiation, apoptosis, cell cycle. The NEDD4 family, belonging to HECT E3 ubiquitin ligases, is reported as regulators that participate in the DDR process by recognizing different substrates. In this review, we summarize recent researches on NEDD4 family members in the DDR and discuss the roles of NEDD4 family members in the cascade reactions induced by DNA damage. This review may contribute to the further study of pathophysiology for certain diseases and pharmacology for targeted drugs.

Transcriptomic analysis reveals that coxsackievirus B3 Woodruff and GD strains use similar key genes to induce FoxO signaling pathway activation in HeLa cells

Coxsackievirus B3 (CVB3) is a major cause of viral myocarditis in humans. Although there have been studies on CVB3 infection and pathogenesis, the precise disease mechanism is still not clear. In this study, we used RNA-seq technology to compare the transcriptomic profile of virus-infected HeLa cells to that of uninfected cells to identify key genes involved in host-virus interaction. For this, two CVB3 strains, CVB3 Woodruff, an experimental strain, and GD16-69/GD/CHN/2016, a clinical strain, were selected to examine the common mechanisms underlying their infection. Transcriptomic profiles revealed increased expression of the cell cycle genes CCNG2, GADD45B, PIM1, RBM15, KLF10, and RIOK3 and decreased expression of CYBA. The autophagy-related genes ATG12 and YOD1 were found to be upregulated, while the expression of SOD2 and XPO1 increased slightly in infected cells, and only a minor change was observed in GABARAP expression. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed the FoxO signaling pathway to be enriched and showed a close interaction with differentially expressed genes (DEGs) in the protein-protein interaction network. DEGs associated with related pathways such as cell cycle, autophagy, and oxidative stress resistance were also confirmed by qRT-PCR. In summary, the FoxO signaling pathway was activated during infection with both CVB3 strains and was found to have a regulatory role in downstream pathways such as cell cycle, autophagy, oxidative stress resistance, and the antiviral immune response.

Integrated Bioinformatics Analysis Reveals Marker Genes and Potential Therapeutic Targets for Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare cardiovascular disease with very high mortality rate. The currently available therapeutic strategies, which improve symptoms, cannot fundamentally reverse the condition. Thus, new therapeutic strategies need to be established. Our research analyzed three microarray datasets of lung tissues from human PAH samples retrieved from the Gene Expression Omnibus (GEO) database. We combined two datasets for subsequent analyses, with the batch effects removed. In the merged dataset, 542 DEGs were identified and the key module relevant to PAH was selected using WGCNA. GO and KEGG analyses of DEGs and the key module indicated that the pre-ribosome, ribosome biogenesis, centriole, ATPase activity, helicase activity, hypertrophic cardiomyopathy, melanoma, and dilated cardiomyopathy pathways are involved in PAH. With the filtering standard (|MM| > 0.95 and |GS| > 0.90), 70 hub genes were identified. Subsequently, five candidate marker genes (CDC5L, AP3B1, ZFYVE16, DDX46, and PHAX) in the key module were found through overlapping with the top thirty genes calculated by two different methods in CytoHubb. Two of them (CDC5L and DDX46) were found to be significantly upregulated both in the merged dataset and the validating dataset in PAH patients. Meanwhile, expression of the selected genes in lung from PAH chicken measured by qRT-PCR and the ROC curve analyses further verified the potential marker genes' predictive value for PAH. In conclusion, CDC5L and DDX46 may be marker genes and potential therapeutic targets for PAH.