https://www.selleckchem.com/products/n6-methyladenosine.html The expression of exogenous PDE5, a non-photoreceptor-specific member of the PDE superfamily, prevents photoreceptor degeneration in rd1 mice. Unlike endogenous photoreceptor-specific PDE6 that was localised in the outer segments of photoreceptors, ectopically-expressed PDE5 was distributed in inner segments and synaptic terminals. PDE5 also promoted the development of the outer segments in rd1 mice. Co-expression of PDE5 and rhodopsin in cultured cells showed enhanced rhodopsin expression. Lowering the cGMP level in photoreceptor by PDE5 is sufficient to rescue photoreceptors in rd1 retinas. cGMP may also be involved in the regulation of rhodopsin expression in photoreceptors. Lowering the cGMP level in photoreceptor by PDE5 is sufficient to rescue photoreceptors in rd1 retinas. cGMP may also be involved in the regulation of rhodopsin expression in photoreceptors. The current coronavirus disease 2019 (COVID-19) pandemic, since first reported in Wuhan, has inspired worldwide efforts to develop effective COVID-19 vaccination strategies. mRNA vaccines encoding COVID-19 antigens gain lead in this global race due to their high effectiveness and simple manufacturing process. Notably, two COVID-19 mRNA vaccines, mRNA-1273 and BNT162b2, have survived in clinical trials and been authorized for emergency use across a range of countries. Recent advances on mRNA vaccine development for COVID-19 are discussed in this perspective, including sequence design, chemical modification, manufacturing process and in vivo delivery. Phase I to IV clinical trials of mRNA-1273 and BNT162b2 are then summarized, respectively. Using mRNA vaccines serves as a promising strategy to achieve mass vaccination in the COVID-19 pandemic. We hope that future studies of mRNA vaccine technology would overcome existing limitations and help people cope with COVID-19. Using mRNA vaccines serves as a promising strategy to achieve mass vaccination i