Direct imaging of single‐molecule and its movement is of fundamental importance in biology, but challenging. Herein, aided by the nanoconfinement effect and resultant high reaction activity within metal–organic frameworks (MOFs), the designed Ru(bpy)32+ embedded MOF complex (RuMOFs) exhibits bright electrochemiluminescence (ECL) emission permitting high‐quality imaging of ECL events at single molecule level. By labeling individual proteins of living cells with single RuMOFs, the distribution of membrane tyrosine‐protein‐kinase‐like7 (PTK7) proteins at low‐expressing cells is imaged via ECL. More importantly, the efficient capture of ECL photons generated inside the MOFs results in a stable ECL emission up to 1 h, allowing the in operando visualization of protein movements at the cellular membrane. As compared with the fluorescence observation, near‐zero ECL background surrounding the target protein with the ECL emitter gives a better contrast for the dynamic imaging of discrete protein movement. This achievement of single molecule ECL dynamic imaging using RuMOFs will provide a more effective nanoemitter to observe the distribution and motion of individual proteins at living cells.

Soybean (Glycine max) is one of the most important crops world-wide. Under low nitrogen (N) condition, soybean can form a symbiotic relationship with rhizobia to acquire sufficient N for their growth and production.Nodulation signaling controls soybean symbiosis with rhizobia. The soybean Nodule Inception (GmNINa) gene is a central regulator of soybean nodulation. However, the transcriptional regulation of GmNINa remains largely unknown. Nodulation is sensitive to salt stress, but the underlying mechanisms are unclear.Here, we identified an NAC transcription factor designated GmNAC181 (also known as GmNAC11) as the interacting protein of GmNSP1a. GmNAC181 overexpression or knockdown in soybean resulted in increased or decreased numbers of nodules, respectively. Accordingly, the expression of GmNINa was greatly up-and downregulated, respectively. Furthermore, we showed that GmNAC181 can directly bind to the GmNINa promoter to activate its gene expression. Intriguingly, GmNAC181 was highly induced by salt stress during nodulation and promoted symbiotic nodulation under salt stress.We identified a new transcriptional activator of GmNINa in the nodulation pathway and revealed a mechanism by which GmNAC181 acts as a network node orchestrating the expression of GmNINa and symbiotic nodulation under salt stress conditions.

Neural interfaces provide a window for bio-signal modulation and recording with the assistance of neural microelectrodes. However, shrinking the size of electrodes results in high electrochemical impedance and low capacitance, thus limiting the stimulation/recording efficiency. In order to achieve critical stability and low power consumption, here, nanocone-shaped platinum (Pt) with an extensive surface area is proposed as an adhesive layer on a bare Pt substrate, followed by the deposition of a thin layer of iridium oxide (IrOx) to fabricate high-performance nanocone-array-based Pt-IrOx neural microelectrodes (200 μm in diameter). A uniform nanocone-shaped Pt with significant roughness is created via controlling the ratio of NH4+ and Pt4+ ions in the electrolyte, which can be widely applicable for batch production on multichannel flexible microelectrode arrays (fMEAs) and various substrates with different dimensions. The Pt-IrOx nanocomposite-coated microelectrode presents a significantly low impedance down to 0.72 ± 0.04 Ω cm2 at 1 kHz (reduction of ~92.95%). The cathodic charge storage capacity (CSCc) and charge injection capacity (CIC) reaches up to 52.44 ± 2.53 mC cm−2 and 4.39 ± 0.36 mC cm−2, respectively. Moreover, superior chronic stability and biocompatibility are also observed. The modified microelectrodes significantly enhance the adhesion of microglia, the major immune cells in the central nervous system. Therefore, such a coating strategy presents great potential for biomedical and other practical applications.

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