RESUMO
N6-methyladenosine (m6A) RNA methylation is the most prevalent internal modification of mammalian messenger RNA. The m6A modification affects multiple aspects of RNA metabolism, including processing, splicing, export, stability, and translation through the reversible regulation of methyltransferases (Writers), demethylases (Erasers), and recognition binding proteins (Readers). Accumulating evidence indicates that altered m6A levels are associated with a variety of human cancers. Recently, dysregulation of m6A methylation was shown to be involved in the occurrence and development of gastric cancer (GC) through various pathways. Thus, elucidating the relationship between m6A and the pathogenesis of GC has important clinical implications for the diagnosis, treatment, and prognosis of GC patients. In this review, we evaluate the potential role and clinical significance of m6A-related proteins which function in GC in an m6A-dependent manner. We discuss current issues regarding m6A-targeted inhibition of GC, explore new methods for GC diagnosis and prognosis, consider new targets for GC treatment, and provide a reasonable outlook for the future of GC research.
RESUMO
The modifier of quantum dots plays an important role in synthesis and nature of quantum dots, however the effect on the interaction between quantum dots and protein is not very clear until up to now. In the present paper, the interactions of CdTe quantum dots with bovine serum album (BSA) were studied by spectroscopy methods including ultraviolet-visible absorption spectrometry (UV-Vis), fluorescence spectrometry (FL) and infrared spectrometry (IR). The CdTe quantum dots were modified by three different thiol-complex including thioglycolic acid, L-cysteine and glutathione, i. e. thioglycolic acid capped CdTe quantum dots (CdTe(T)), L-cysteine capped CdTe quantum dots (CdTe(L)) and glutathione capped CdTe quantum dots (CdTe(G)) respectively. The quenching constant K(sv) and corresponding thermodynamic parameters, such as enthalpy change (deltaH(theta)), entropy change (deltaS(theta)), Gibbs free energy change (deltaG(theta)), were calculated according to Stern-Volmer equations. The results showed that CdTe(T), CdTe(L) and CdTe(G) all have a strong ability of quenching the fluorescence of bovine serum albumin, and the interactions of the three types of thiol-capped CdTe quantum dots with BSA were static quenching process. The quenching constant of K(sv)(TGA) is similar to K(sv)(GSH), which is much less than K(sv)(L-Cys). The binding forces of CdTe(T) and CdTe(L) with the BSA were the main contributions from hydrophobic force according to the thermodynamic parameters (deltaH(theta) > 0, deltaS(theta) > 0 and deltaG(theta) < 0), while the binding forces of CdTe(G) with BSA were composed of both hydrogen bonding force and hydrophobic force according to the thermodynamic parameters(deltaH(theta) < 0, deltaS(theta) > 0 and deltaG(theta) < 0). It was found that different functional group and molecular volume size of thiol surface modified reagent played an important role in the interactions between CdTe QDs and BSA.
