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RNA-binding proteins (RBPs) closely regulate the whole lifecycle of most RNA molecules, from the very early stage of transcription to RNA decay. Dysregulation of RBPs significantly affects the fate of cancer-related transcripts. Therefore, it is imperative to fully understand the complicated RBP-RNA regulatory networks in malignant diseases and to explore novel therapeutic targets. The RBP DAZAP1 (deleted in azoospermia-associated protein 1), originally identified as an important protein in spermatogenesis, had rarely been studied in the context of carcinogenesis. The role of DAZAP1 in hepatocellular carcinoma (HCC) was unveiled in this study. The relative expression of DAZAP1 was significantly upregulated in HCC and was positively associated with several key malignant characteristics and poor postoperative survival in patients. DAZAP1 knockdown by small interfering RNA markedly inhibited HCC cell proliferation, migration and invasion. Furthermore, DAZAP1 significantly reduced cellular sensitivity to sorafenib (SF), which had been proven to be an inducer of ferroptosis by targeting the system Xc− (composed of a light chain, xCT/SLC7A11, and a heavy chain, 4F2 heavy chain). At the mechanistic level, DAZAP1 was identified as a potent inhibitor of ferroptosis and an efficient binding partner of SLC7A1 1 mRNA. Further study revealed that DAZAP1 interacted with the 3′UTR (untranslated region) of SLC7A1 1 mRNA and positively regulated its stability. In our work, we clarified novel functions of DAZAP1 and preliminarily revealed its underlying mechanism in ferroptosis, which may be conducive to the exploration of biomarkers and therapeutic targets in HCC patients. • DAZAP1 effectively promotes HCC progression. • DAZAP1 negatively regulates ferroptosis in HCC cells. • DAZAP1 interacts with SLC7A1 1 mRNA, and positively regulates its stability. [ABSTRACT FROM AUTHOR]

Several novel orange emission supramolecular phosphorescent polymers (SPPs) with different counterions of PF 6 −, Br− and BIm 4 - have been developed for polymer light-emitting diodes. The formation of SPPs, utilizing efficient non-bonding assembly of dibenzo-24-crown-8-tethered iridium complex and dibenzylammonium-functionalized fluorene-dibenzothiophene-S,S-dioxide cooligomer, are monitored by 1H NMR and viscosity measurement. The influences of different counterions on the optical, thermal and electroluminescent (EL) properties of the resulting SPPs, as well as the supramolecular assembly behavior are investigated in detail. These SPPs display high glass transition temperatures of ca. 100 °C. The single-emissive-layer PLED with SPP-PF 6 exhibits the highest device efficiency of 12.32 cd A−1 with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.57, 0.43). More importantly, owing to "spacer" effect of the large BIm 4 - counterion, the device based on SPP-BIm 4 show very low efficiency roll-off. Supramolecular phosphorescent polymers (SPPs) with different counterions of PF 6 −, Br− and BIm 4 - have been developed for orange polymer light-emitting diodes, which exhibit good thermal stability and excellent electroluminescent properties. Image 1 • SPPs with different counterions of PF 6 −, Br− and BIm 4 - are obtained. • All the SPPs display orange light-emitting with a CIE coordinates of (0.57, 0.43). • The PLEDs based on SPP-PF 6 exhibited a highest LE of 12.32 cd A−1. • Due to "spacer" effect, the device with SPP-BIm 4 shows very low efficiency roll-off. [ABSTRACT FROM AUTHOR]

Ensuring the large signal stability of the DC microgrid is the premise of the safe operation of the DC microgrid, but the research on the large-signal stability of microgrids with multiple droop control micro-sources is still scarce. In this paper, a DC microgrid system model with multiple droop control micro-sources was established by appropriate simplification. Addressing the problem that most stability research methods cannot be quantitatively analyzed, the mixed potential function method was used to analyze the large signal stability of the system. However, the criterion obtained by the conventional mixed potential function method is complicated and contains multiple time-varying parameters, which is not convenient for analysis. Therefore, the simple form of the criterion was obtained through simplification and the analysis proved the rationality of the simplification. On this basis, a nonlinear droop control method was proposed to improve the anti-interference ability of the system. Finally, the accuracy of the large signal stability criterion and the effectiveness of nonlinear droop control on the system's large signal stability were verified by simulation. [ABSTRACT FROM AUTHOR]