Deciphering the Epitranscriptomic Signatures in Cell Fate Determination and Development.

Precise regulation of transcriptome modulates several vital aspects in an organism that includes gene expression, cellular activities and development, and its perturbation ensuing pathological conditions. Around 150 post-transcriptional modifications of RNA have been identified till date, which are evolutionarily conserved and likewise prevalent across RNA classes including messenger RNA (mRNA), transfer RNA (tRNA), ribosomal RNA (rRNA), and detected less frequently in small nuclear RNA (snRNA) and microRNAs (miRNA). Among the RNA modifications documented, N6-methyladenosine (m6A) is the best characterised till date. Also, N1-methyladenosine (m1A), 5-methylcytosine (m5C) and pseudouridine (Ψ) are some of the other prominent modifications detected in coding and non-coding RNAs. "Epitranscriptome", ensemble of these post-transcriptional RNA modifications, precisely coordinates gene expression and biological processes. Current literatures suggest the critical involvement of epitranscriptomics in several organisms during early development, contributing to cell fate specification and physiology. Indeed, epitranscriptomics similar to DNA epigenetics involves combinatorial dynamics provided by modified RNA molecules and associated protein complexes, which function as "writers", "erasers" and "readers" of these modifications. A novel code orchestrating gene expression during cell fate determination is generated by the coordinated effects of different classes of modified RNAs and its regulator proteins. In this review, we summarize the current knowhow on N6-methyladenosine (m6A), 5-methylcytosine (m5C) and pseudouridine (ψ) modifications in RNA, the associated regulator proteins and enumerate how the epitranscriptomic regulations are involved in cell fate determination.

Influence of doping ion, capping agent and pH on the fluorescence properties of zinc sulfide quantum dots: Sensing of Cu2+ and Hg2+ ions and their biocompatibility with cancer and fungal cells.

Herein, a facile one-pot synthetic method was explored for the fabrication of glutathione capped Mn2+ doped­zinc sulphide quantum dots (GSH-Mn2+-ZnS QDs) for both fluorescent detection of Cu2+ and Hg2+ ions and for fluorescence imaging of two cancer (RIN5F and MDAMB231) and fungal (Rhizopus oryzae) cells. Particularly, doping of Mn2+ into ZnS QDs nanocrystal structure resulted a great improvement in the fluorescence properties of ZnS QDs. The emission peak of undoped ZnS QDs was found at 447 nm, which is due to the large number of surface defects in the ZnS QDs nanostructures. Under identical conditions, there is a good linear relationship between the quenching of fluorescence intensity and analytes (Cu2+ and Hg2+ ions) concentration in the range of 0.005 to 0.2 mM and of 0.025 to 0.4 mM for Cu2+ and Hg2+ ions, respectively. The GSH-Mn2+-ZnS QDs exhibit least cytotoxicity against RIN5F and MDAMB231 cells, demonstrating the multifunctional applications in sensing of metal ions and biocompatibility towards cancer (RIN5F and MDAMB231) and fungal (Rhizopus oryzae) cells.