Self-labeling protein tags can introduce advanced molecular motifs to specific cellular proteins.Here we introduce the third-generation covalent TMPtag (TMP-tag3) and showcase its comparison with HaloTag and SNAP-tag. TMP-tag3 is based on a proximity-induced covalent Michael addition between an engineered Cys of E. coli dihydrofolate reductase (eDHFR) and optimized trimethoprim (TMP)acrylamide conjugates with minimal linkers. Compared to previous versions, the TMP-tag3 features an enhanced permeability when conjugated to fluorogenic spirocyclic rhodamines. As a small protein, the 18-kD eDHFR is advantageous in tagging selected mitochondrial proteins which are less compatible with bulkier HaloTag fusions. The proximal NÀ C termini of eDHFR also enable facile insertion into various protein loops. TMP-tag3, HaloTag, and SNAP-tag are orthogonal to each other, collectively forming a toolbox for multiplexed live-cell imaging of cellular proteins under fluorescence nanoscopy.

No abstract

Recently, full duplex (FD) has been attracting great attention, due to its capability to double the spectral efficiency. In this paper, we focus on a FD wireless communication network, in which a FD base station (BS) and a half duplex (HD) mobile station (MS) exchange their information via a HD relay station (RS) within two phases. An amplify-and-forward (AF) relaying scheme and a decode-and-forward (DF) relaying scheme are proposed for the two-way relay network. In the proposed DF relaying scheme, the RS chooses the best DF relaying mode according to channel state information (CSI) to achieve the maximum capacity. Specifically, the RS can decode and forward data streams from both the BS and MS, or only one of them, or none of them, and thus obtaining a selection diversity gain. In order to analyze the performance of the proposed schemes, achievable rate regions and sum-capacities of the proposed schemes are derived in closed form. Numerical and simulation results show that the proposed relaying schemes provide significant capacity gain.

Self-labeling protein tags can introduce advanced molecular motifs to specific cellular proteins.Here we introduce the third-generation covalent TMPtag (TMP-tag3) and showcase its comparison with HaloTag and SNAP-tag. TMP-tag3 is based on a proximity-induced covalent Michael addition between an engineered Cys of E. coli dihydrofolate reductase (eDHFR) and optimized trimethoprim (TMP)acrylamide conjugates with minimal linkers. Compared to previous versions, the TMP-tag3 features an enhanced permeability when conjugated to fluorogenic spirocyclic rhodamines. As a small protein, the 18-kD eDHFR is advantageous in tagging selected mitochondrial proteins which are less compatible with bulkier HaloTag fusions. The proximal NÀ C termini of eDHFR also enable facile insertion into various protein loops. TMP-tag3, HaloTag, and SNAP-tag are orthogonal to each other, collectively forming a toolbox for multiplexed live-cell imaging of cellular proteins under fluorescence nanoscopy.