A novel nucleic acid linker for multi-gene expression enhances plant and animal synthetic biology.

The production of compact vectors for gene stacking is hindered by a lack of effective linkers. Here, we report that a 26-nt nucleic acid linker, NAL1, from the fungus Glarea lozoyensis and its truncated derivatives could connect two genes as a bicistron, enabling independent translation in a maize protoplast transient expression system and human 293 T cells. The optimized 9-nt NAL10 linker was then used to connect four genes driven by a bidirectional promoter; this combination was successfully used to reconstruct the astaxanthin biosynthesis pathway in transgenic maize. The short and efficient nucleic acid linker NAL10 can be widely used in multi-gene expression and synthetic biology in animals and plants.

Identification and characterization of yellow stripe-like genes in maize suggest their roles in the uptake and transport of zinc and iron.

BACKGROUND: Yellow Stripe-Like (YSL) proteins are involved in the uptake and transport of metal ions. They play important roles in maintaining the zinc and iron homeostasis in Arabidopsis, rice (Oryza sativa), and barley (Hordeum vulgare). However, proteins in this family have not been fully identified and comprehensively analyzed in maize (Zea mays L.). RESULTS: In this study, we identified 19 ZmYSLs in the maize genome and analyzed their structural features. The results of a phylogenetic analysis showed that ZmYSLs are homologous to YSLs of Arabidopsis and rice, and these proteins are divided into four independent branches. Although their exons and introns have structural differences, the motif structure is relatively conserved. Analysis of the cis-regulatory elements in the promoters indicated that ZmYSLs might play a role in response to hypoxia and light. The results of RNA sequencing and quantitative real-time PCR analysis revealed that ZmYSLs are expressed in various tissues and respond differently to zinc and iron deficiency. The subcellular localization of ZmYSLs in the protoplast of maize mesophyll cells showed that they may function in the membrane system. CONCLUSIONS: This study provided important information for the further functional analysis of ZmYSL, especially in the spatio-temporal expression and adaptation to nutrient deficiency stress. Our findings provided important genes resources for the maize biofortification.

Perimeter monitoring of urban buried pipeline threated by construction activities based on distributed fiber optic sensing and real-time object detection.

Urban construction activities seriously jeopardize the security of buried pipeline. Distributed optical fiber vibration monitoring is one of the most promising ways to prevent third-party threats, of which the biggest challenge is to quickly and accurately detect rare abnormal events from extremely large amounts of time-space raw data. By analogy with image recognition, the task here is similar to object detection if considering the time-space optical signals as the grayscale images and the abnormal events as the objects. Given this, what we believe to be a novel monitoring method is proposed, which consists of two Faster R-CNN models, a max pooling layer and a monitoring strategy. In the field tests, the 86-hour optical vibration signals for 5.25 km distance are recognized within 6.6 minutes with the recognition rate of 98.85% for construction activities, and only two false alarms are issued. The proposed method can reduce the recognition time by 99.59% compared to the CNN-based method.