Large amounts of pumice stone generated by the submarine volcanic eruption at Fukutoku Okanoba on August 13, 2021, drifted ashore, affecting ship navigation and fishery operations. Through laboratory experiments, we investigated the possibility of using pumice as a sand-capping material for eutrophic sediments. Crushed pumice as a sand cover material effectively reduced the sedimentary oxygen consumption rate. Nutrient release from sediment showed a similar trend, with ~25% and 82% reduction in NH4-N and PO4-P release rates, respectively. Furthermore, the bivalve exposure experiments using crushed pumice suspended in seawater showed no adverse effects specific to pumice and lower bivalve mortality than that using kaolin at the same concentration. This could be owing to differences in gill accumulation and blockage owing to the particle size variation of the suspended particles. These results suggest that crushed pumice is effective for sand covering and suppresses oxygen consumption and nutrient release from the sediments.

Although RNA modifications were discovered decades ago, the identification of enzymes that write, read, and erase RNA modifications enabled their functional study and spawned the field of epitranscriptomics. Coupling that knowledge to new methods has enabled the precise pinpointing of epitranscriptomic modifications across the transcriptome plus the elucidation of their functional consequences. PCIF1 (Phosphorylated CTD Interacting Factor 1) was shown to add N6, 2’-O-dimethyladenosine (m⁶Am) marks at the first nucleotide after the 5’ N7-methylguanosine (m⁷G) cap. In this review, we discuss the epitranscriptomic regulation of mRNA in general, and focus on m⁷G cap-adjacent m⁶Am in particular. m⁶Am positions can now be distinguished from N6-methyladenosine (m⁶A) using new techniques leveraging PCIF1-knockout cells. Although m⁶Am modification sites can be detected precisely, conflicting data have been published regarding how cap-adjacent m⁶Am marks affect their host mRNA. Discrepancies in the data mean that the effects of cap-adjacent m⁶Am on mRNA stability, decapping, and translation continue to be debated. Finally, while PCIF1 is predominantly nuclear, a subset of results suggest a possible cytoplasmic role as well. Taken together, these contradictory results which employed different methodologies and cell lines means that further experiments are required to determine the ultimate biological function(s) of m⁷G cap-adjacent m⁶Am.

Keywords: Trichoderma sp., biogenic selenium nanoparticles, capping biomolecules, bio-corona, agriculture, plant biostimulants, phytopathogens, physicochemical properties, bioactivity mechanism