SummaryTransfer RNA (tRNA) is a central component of protein synthesis and cell signaling network. One salient feature of tRNA is its heavily modified status, which can critically impact its function. Here we show that mammalian ALKBH1 is a tRNA demethylase. It mediates the demethylation of N 1 -methyladenosine (m 1 A) in tRNAs. The ALKBH1-catalyzed demethylation of the target tRNAs results in attenuated translation initiation and their decreased usage in protein synthesis. This process is dynamic and responds to glucose availability to affect translation. Our results uncover reversible methylation of tRNA as a new regulatory mechanism of post-transcriptional gene expression. In briefReversible tRNA methylation helps translation respond to nutrient availability.

We describe the precise shaping and mode-resolved amplitude and phase characterization of optical arbitrary waveforms by using a 20 GHz optical frequency comb and integrated 64 x 20 GHz channel arrayed waveguide grating pair. Complex waveforms with large variations in phase and amplitude between adjacent modes were generated and characterized.

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Vertical and differential deformations in super‐high‐rise buildings are extremely important during construction. In order to be able to adjust the construction process accurately, taking the deformations into account, such deformations must be calculated exactly. The analysis of the vertical deformations of the high‐rise Shanghai World Financial Centre building is illustrated in this paper. The prediction models of CEB‐FIP 90 are used for calculating shrinkage and creep. The fictitious degree of hydration method has been applied for calculating the creep behaviour of the early‐age concrete. The influence of steel bars on the vertical deformations has been analysed based on the macroscopical modulus method. Calculation of the vertical deformations includes the pre‐construction and the post‐construction deformations. Finally, the differential deformation between the concrete and the mega‐structure column is determined. Theoretical results for the vertical displacement of this super‐high‐rise building agree very well with field monitoring data.