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Translational control of transcription factor ATF4 through paired upstream ORFs (uORFs) plays an important role in eukaryotic gene regulation. While it is typically induced by phosphorylation of eIF2α, ATF4 translation can be also induced by expression of a translational inhibitor protein, eIF5-mimic protein 1 (5MP1, also known as BZW2) in mammals. Here we show that the 5MP gene is maintained in eukaryotes under strong purifying selection, but is uniquely missing in two major phyla, nematoda and ascomycota. The common function of 5MP from protozoa, plants, fungi and insects is to control translation by inhibiting eIF2. The affinity of human 5MP1 to eIF2β was measured as being equivalent to the published value of human eIF5 to eIF2β, in agreement with effective competition of 5MP with eIF5 for the main substrate, eIF2. In the red flour beetle, Tribolium castaneum, RNA interference studies indicate that 5MP facilitates expression of GADD34, a downstream target of ATF4. Furthermore, both 5MP and ATF4 are essential for larval development. Finally, 5MP and the paired uORFs allowing ATF4 control are conserved in the entire metazoa except nematoda. Based on these findings, we discuss the phylogenetic and functional linkage between ATF4 regulation and 5MP expression in this group of eukaryotes.

Recent studies have shown high usage of the IGHV1-69 germline immunoglobulin gene for influenza hemagglutinin stem-directed broadly-neutralizing antibodies (HV1-69-sBnAbs). Here we show that a major structural solution for these HV1-69-sBnAbs is achieved through a critical triad comprising two CDR-H2 loop anchor residues (a hydrophobic residue at position 53 (Ile or Met) and Phe54), and CDR-H3-Tyr at positions 98±1; together with distinctive V-segment CDR amino acid substitutions that occur in positions sparse in AID/polymerase-η recognition motifs. A semi-synthetic IGHV1-69 phage-display library screen designed to investigate AID/polη restrictions resulted in the isolation of HV1-69-sBnAbs that featured a distinctive Ile52Ser mutation in the CDR-H2 loop, a universal CDR-H3 Tyr at position 98 or 99, and required as little as two additional substitutions for heterosubtypic neutralizing activity. The functional importance of the Ile52Ser mutation was confirmed by mutagenesis and by BCR studies. Structural modeling suggests that substitution of a small amino acid at position 52 (or 52a) facilitates the insertion of CDR-H2 Phe54 and CDR-H3-Tyr into adjacent pockets on the stem. These results support the concept that activation and expansion of a defined subset of IGHV1-69-encoded B cells to produce potent HV1-69-sBnAbs does not necessarily require a heavily diversified V-segment acquired through recycling/reentry into the germinal center; rather, the incorporation of distinctive amino acid substitutions by Phase 2 long-patch error-prone repair of AID-induced mutations or by random non-AID SHM events may be sufficient. We propose that these routes of B cell maturation should be further investigated and exploited as a pathway for HV1-69-sBnAb elicitation by vaccination.

In technology-infused frontline service encounters, human-based service represents a high degree of uncertainty. However, understanding how technology can meet customer demands without undermining the importance of human interaction is crucial for retailers to remain competitive. However, empirical evidence comparing different types of service encounters (technology-facilitated vs. technology-assisted vs. technology-free) is lacking. Building on existing approaches to technology-enabled services, this study aims to extend the understanding of the optimal type of technology infusion and human interaction in the context of customer trust and willingness to pay. Drawing on social interaction theory, emphasizing that technology can influence the nature and quality of interactions between customers and frontline employees, this paper empirically examines different types of service encounters. A quasi-experimental online study (N = 944) was conducted.General results show that technology infusion within the service encounter has a negative impact on customers' trust in the frontline employee, but a positive impact on customers' willingness to pay. Furthermore, a mediating influence of customers' perceptions of the competence of frontline employees can be demonstrated. The results show that customers place more value on a technology-facilitated encounter than on a technology-assisted service. Based on the findings, this paper derives implications for retail managers at various levels. Since the customer's perception of the competence of front-line employees in using a technology is of high relevance to the customer, the retailer should pay more attention to training employees in the use of these technologies in their interactions with customers because of the perception of service competence and other relationship-building criteria such as trust. In addition, the competent use of these technologies and the customer's perception of them can also affect the customer's willingness to pay and thus the success of the business. [ABSTRACT FROM AUTHOR]