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Calmodulins (CaMs) and calmodulin-like proteins (CMLs) belong to families of calcium-sensors that act as calcium ion (Ca2+) signal-decoding proteins and regulate downstream target proteins. As a tropical halophyte, Canavalia rosea shows great resistance to multiple abiotic stresses, including high salinity/alkalinity, extreme drought, heat, and intense sunlight. However, investigations of calcium ion signal transduction involved in the stress responses of C. rosea are limited. The CaM and CML gene families have been identified and characterized in many other plant species. Nevertheless, there is limited available information about these genes in C. rosea. In this study, a bioinformatic analysis, including the gene structures, conserved protein domains, phylogenetic relationships, chromosome distribution, and gene synteny, was comprehensively performed to identify and characterize CrCaMs and CrCMLs. A spatio-temporal expression assay in different organs and environmental conditions was then conducted using the RNA sequencing technique. Additionally, several CrCaM and CrCML members were then cloned and functionally characterized using the yeast heterogeneous expression system, and some of them were found to change the tolerance of yeast to heat, salt, alkalinity, and high osmotic stresses. The results of this study provide a foundation for understanding the possible roles of the CrCaM and CrCML genes, especially for halophyte C. rosea's natural ecological adaptability for its native habitats. This study also provides a theoretical basis for further study of the physiological and biochemical functions of plant CaMs and CMLs that are involved in tolerance to multiple abiotic stresses. [ABSTRACT FROM AUTHOR]

Thaumatin-like proteins (TLPs), including osmotins, are multifunctional proteins related to plant biotic and abiotic stress responses. TLPs are often present as large multigene families. Tetragonia tetragonoides (Pall.) Kuntze (Aizoaceae, 2n = 2x = 32), a vegetable used in both food and medicine, is a halophyte that is widely distributed in the coastal areas of the tropics and subtropics. Saline–alkaline soils and drought are two major abiotic stress factors significantly affecting the distribution of tropical coastal plants. The expression of stress resistance genes would help to alleviate the cellular damage caused by abiotic stress factors such as high temperature, salinity–alkalinity, and drought. This study aimed to better understand the functions of TLPs in the natural ecological adaptability of T. tetragonoides to harsh habitats. In the present study, we used bioinformatics approaches to identify 37 TtTLP genes as gene family members in the T. tetragonoides genome, with the purpose of understanding their roles in different developmental processes and the adaptation to harsh growth conditions in tropical coral regions. All of the TtTLPs were irregularly distributed across 32 chromosomes, and these gene family members were examined for conserved motifs of their coding proteins and gene structure. Expression analysis based on RNA sequencing and subsequent qRT-PCR showed that the transcripts of some TtTLPs were decreased or accumulated with tissue specificity, and under environmental stress challenges, multiple TtTLPs exhibited changeable expression patterns at short (2 h), long (48 h), or both stages. The expression pattern changes in TtTLPs provided a more comprehensive overview of this gene family being involved in multiple abiotic stress responses. Furthermore, several TtTLP genes were cloned and functionally identified using the yeast expression system. These findings not only increase our understanding of the role that TLPs play in mediating halophyte adaptation to extreme environments but also improve our knowledge of plant TLP evolution. This study also provides a basis and reference for future research on the roles of plant TLPs in stress tolerance and ecological environment suitability. [ABSTRACT FROM AUTHOR]

In numerous studies, it is imperative to establish a homogeneous refractive index (RI) surrounding environment to acquire a surface lattice resonance (SLR) characteristic peak for a plasmonic array. However, this requirement will limit the practical applicability of the SLR. This study successfully achieved the fabrication of cost-efficient, size-adjustable, and structure-transferable two-dimensional (2D) ordered gold (Au) near-spherical nanoparticle (NP) arrays with large NP size (>100 nm) through utilizing a colloidal crystal template and annealing process. In this method, the NP diameter can be adjusted by varying the thickness of the deposited Au film. Importantly, the fabricated 2D Au NP arrays with larger NP size supported an obvious and sharp SLR peak by exciting with normal incident light in an asymmetric air environment. These results indicated that if the arrays were well arranged and the NP size was large enough, index-matching was not necessary for the formation of far-field electromagnetic coupling of the plasmonic NPs. Furthermore, theoretical calculation demonstrated that the significant SLR signal in air environment was relevant to the NP size. Due to the obvious SLR peak in air, the 2D Au NP arrays were applied as a sensor to detect hemoglobin (Hb). It was found that the SLR peak was more sensitive than the localized surface plasmon resonance (LSPR) peak, and its offset was obviously observed when the Hb concentration was as low as 10 μM. Moreover, the Au NP arrays also displayed good uniformity and stability. Besides rigid nanophotonic sensor, the prepared 2D Au NP arrays on a quartz substrate can be transferred to a flexible substrate to form a flexible free-standing optical sensor, providing a real-time tunable SLR mode. With the decrease of water content, the SLR peak continuously blue-shifted from 1058 nm to 605 nm, displaying high sensitivity. This paper not only provides a cost-effective and controllable approach to fabricate next-generation rigid and flexible nanophotonic devices, but also paves the way for practical application of SLR in sensing. [ABSTRACT FROM AUTHOR]

Ionizing radiation (IR)‐induced intestinal injury is usually accompanied by high lethality. Intestinal stem cells (ISCs) are critical and responsible for the regeneration of the damaged intestine. Astragalus polysaccharide (APS), one of the main active ingredients of Astragalus membranaceus (AM), has a variety of biological functions. This study was aimed to investigate the potential effects of APS on IR‐induced intestine injury via promoting the regeneration of ISCs. We have established models of IR‐induced intestinal injury and our results showed that APS played great radioprotective effects on the intestine. APS improved the survival rate of irradiated mice, reversed the radiation damage of intestinal tissue, increased the survival rate of intestinal crypts, the number of ISCs and the expression of intestinal tight junction‐related proteins after IR. Moreover, APS promoted the cell viability while inhibited the apoptosis of MODE‐K. Through organoid experiments, we found that APS promoted the regeneration of ISCs. Remarkably, the results of network pharmacology, RNA sequencing and RT‐PCR assays showed that APS significantly upregulated the HIF‐1 signalling pathway, and HIF‐1 inhibitor destroyed the radioprotection of APS. Our findings suggested that APS promotes the regeneration of ISCs through HIF‐1 signalling pathway, and it may be an effective radioprotective agent for IR‐induced intestinal injury. [ABSTRACT FROM AUTHOR]

Tetragonia tetragonoides (Pall.) Kuntze (Aizoaceae, 2n = 2x = 32), a vegetable used for both food and medicine, is a halophyte that is widely distributed in the coastal areas of the tropics and subtropics. Saline–alkaline soils and drought stress are two major abiotic stressors that significantly affect the distribution of tropical coastal plants. Abscisic acid-, stress-, and ripening-induced (ASR) proteins belong to a family of plant-specific, small, and hydrophilic proteins with important roles in plant development, growth, and abiotic stress responses. Here, we characterized the ASR gene family from T. tetragonoides, which contained 13 paralogous genes, and divided TtASRs into two subfamilies based on the phylogenetic tree. The TtASR genes were located on two chromosomes, and segmental duplication events were illustrated as the main duplication method. Additionally, the expression levels of TtASRs were induced by multiple abiotic stressors, indicating that this gene family could participate widely in the response to stress. Furthermore, several TtASR genes were cloned and functionally identified using a yeast expression system. Our results indicate that TtASRs play important roles in T. tetragonoides' responses to saline–alkaline soils and drought stress. These findings not only increase our understanding of the role ASRs play in mediating halophyte adaptation to extreme environments but also improve our knowledge of plant ASR protein evolution. [ABSTRACT FROM AUTHOR]

Cryptotanshinone (CPT), a major biological active ingredient extracted from root of Salvia miltiorrhiza (Danshen), has shown several pharmacological activities. However, the effect of CPT on radiation‐induced lung fibrosis (RILF) is unknown. In this study, we explored the protective effects of CPT on RILF from gut‐lung axis angle, specifically focusing on the bile acid (BA)‐gut microbiota axis. We found that CPT could inhibit the process of epithelial mesenchymal transformation (EMT) and suppress inflammation to reduce the deposition of extracellular matrix in lung fibrosis in mice induced by radiation. In addition, 16S rDNA gene sequencing and BAs‐targeted metabolomics analysis demonstrated that CPT could improve the dysbiosis of gut microbiota and BA metabolites in RILF mice. CPT significantly enriched the proportion of the beneficial genera Enterorhabdus and Akkermansia, and depleted that of Erysipelatoclostridium, which were correlated with increased intestinal levels of several farnesoid X receptor (FXR) natural agonists, such as deoxycholic acid and lithocholic acid, activating the FXR pathway. Taken together, these results suggested that CPT can regulate radiation‐induced disruption of gut microbiota and BAs metabolism of mice, and reduce the radiation‐induced lung inflammation and fibrosis. Thus, CPT may be a promising drug candidate for treating RILF. [ABSTRACT FROM AUTHOR]