Volume 15 Issue 9, September 2019

The N⁶-methyladenosine modification on RNA affects almost all steps of RNA metabolism. A new approach, using the CRISPR-based technology to modulate m⁶A level in mRNA, enables direct functional interrogation of site-specific m⁶A.

An unusual terpene nucleoside, 1-TbAd, made by pathogenic mycobacteria acts as an antacid to block mycobacterial degradation in host cell vacuoles. The antacid activity acts to reduce acidity by neutralizing the pH of these degradative cell organelles.

Asymmetric cell division, which generates daughter cells with distinct characteristics, is a mechanism for creating complex systems through cellular differentiation. Two studies in this issue develop synthetic platforms that program spatial localization of genetic material or signaling molecules to enable asymmetric cell division in Escherichia coli.

Analysis of recent X-ray crystallography data on eukaryotic glycosyltransferases in complex with acceptor and donor substrates reveals structural features that govern substrate specificity and glycosylation site selection.

Fusion of Cas9 with m6A writers METTL3 and METTL14 or eraser ALKBH5 enables site-specific writing or erasing of RNA m6A modifications in mammalian cells and investigation of individual m6A modification-mediated function.

The iron chaperone poly(rC)-binding protein 1 (PCBP1) coordinates ferrous iron via its KH3 domain and, together with BolA2 and glutathione, forms a complex that is required for the assembly of [2Fe–2S] clusters on the cytosolic BolA2–Glrx3 chaperone.

Split Cpf1 pairs are identified to enable chemical- and light-induced genome editing via dimerization. Another pair of split Cpf1 can be used to activate gene expression with high efficiency in cells and in mice.

Buter et al. elucidated the biological function of the terpene nucleoside 1-TbAd, which is made abundantly by virulent but not avirulent Mycobacterium tuberculosis strains, and demonstrate that 1-TbAd regulates the pH and function of host macrophage endolysosomes.

A bacterial 2-hydroxyacyl-CoA lyase catalyzes ligation of carbonyl-containing molecules of different chain lengths with formyl-CoA to produce elongated 2-hydroxyacyl-CoAs, enabling a one-carbon bioconversion pathway with formaldehyde as a substrate.

Inhibition of fatty acid synthase, FASN, blocks innate immune signaling through TLR/MyD88 in neutrophils by blocking palmitoylation of MyD88 by palmitoyltransferase zDHHC6 and improves outcomes in two mouse models of sepsis.

The chromosomal partitioning system (par) of Caulobacter crescentus was repurposed to create an inducible genetic circuit for asymmetric plasmid partitioning and cell division in Escherichia coli.

Small molecule or light-inducible gene circuits in Escherichia coli enable asymmetric cell pole localization of diguanylate phosphodiesterase and facilitate asymmetric cell division regulated by c-di-GMP-responsive transcription factors.