AQP4-DARPin1: A Chimeric Antigen Based on Scaffold Protein DARPin for Efficient Detection of AQP4-IgG in NMOSD.

AQP4-IgG is an autoantibody associated with neuromyelitis optica spectroscopic disorder (NMOSD), a central nervous system inflammatory disease that requires early diagnosis and treatment. We designed two fusion proteins, AQP4-DARPin1 and AQP4-DARPin2, comprising the complete antigenic epitopes of aquaporin-4 (AQP4) and the constant region of the scaffold protein DARPin. These fusion proteins were expressed and purified from Escherichia coli and coated on microplates to develop an efficient method for detecting AQP4-IgG. Molecular dynamics simulation revealed that the fusion of AQP4 extracellular epitopes with DARPin did not alter the main structure of DARPin. The purified AQP4-DARPins bound recombinant antibody rAb-53 (AQP4-IgG) with affinities of 135 and 285 nM, respectively. Enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation demonstrated that AQP4-DARPin1 specifically recognized AQP4-IgG in the NMOSD patient serum. AQP4-DARPin1 as a coated antigen showed higher ELISA signal and end point dilution ratio than full-length AQP4. Our AQP4-DARPin1-coated AQP4-IgG ELISA had 100% specificity and 90% sensitivity. These results indicate that AQP4-DARPin1, compared to existing detection strategies that use full-length or extracellular loop peptides of AQP4, provides a new and more effective approach to the ELISA detection of NMOSD.

Selective penetration of fullerenol through pea seed coats mitigates osmosis-repressed germination via chromatin remodeling and transcriptional reprograming.

BACKGROUND: The alteration of chromatin accessibility plays an important role in plant responses to abiotic stress. Carbon-based nanomaterials (CBNMs) have attracted increasing interest in agriculture due to their potential impact on crop productivity, showcasing effects on plant biological processes at transcriptional levels; however, their impact on chromatin accessibility remains unknown. RESULTS: This study found that fullerenol can penetrate the seed coat of pea to mitigate the reduction of seed germination caused by osmotic stress. RNA sequencing (RNA-seq) revealed that the application of fullerenol caused the high expression of genes related to oxidoreduction to return to a normal level. Assay for transposase accessible chromatin sequencing (ATAC-seq) confirmed that fullerenol application reduced the overall levels of chromatin accessibility of numerous genes, including those related to environmental signaling, transcriptional regulation, and metabolism. CONCLUSION: This study suggests that fullerenol alleviates osmotic stress on various fronts, encompassing antioxidant, transcriptional, and epigenetic levels. This advances knowledge of the working mechanism of this nanomaterial within plant cells. © 2024 Society of Chemical Industry.

Nutrient content and resorption efficiency of leaves of broad-leaved trees along altitudes in Wuyi Mountains, China.

To reveal the variation of leaf nutrient utilization strategies with altitude gradient in subtropical mountain broadleaved trees, 44 species of broadleaved trees at different altitudes (1400, 1600 and 1800 m) in Wuyi Mountains were selected to measure nutrient content, stoichiometric ratio, and nutrient resorption efficiency of green and senescent leaves, and analyzed their allometric growth relationships. The results showed that nitrogen (N) and phosphorus (P) contents in green leaves were significantly higher than those in senescent leaves, which increased with the increases of altitude. The average values of phosphorus resorption efficiency (PRE) and nitrogen resorption efficiency (NRE) were 48.3% and 34.9%, respectively. PRE was significantly higher than NRE. There was no significant difference in nutrient resorption efficiency with altitude. NRE had positive isokinetic growth with and mature leaf N content at low altitude (1400 m) and negative allometry growth with senescent leaf N content at high altitude (1800 m). PRE and N and P contents of senescent leaves had negative isokinetic growth at low altitude (1400 m) and negative allometry growth at high altitudes (1600 and 1800 m). PRE-NRE allometric growth index was 0.95 at each altitude. The nutrient contents of green and senescent leaves increased with the increases of altitude, but altitude did not affect nutrient resorption efficiency. Plants preferred to re-absorbed P from senescent leaves. Nutrient resorption efficiency of leaves at high altitude affected the nutrient status of senescent leaves.

Genome-wide analysis of the SMXL gene family in common bean and identification of karrikin-responsive PvSMXL2 as a negative regulator of PEG-induced drought stress.

Common bean (Phaseolus vulgaris L.) is a major legume crop worldwide, but its growth and development frequently face challenges due to abiotic stresses, particularly drought. Proper supplement of copper could mitigate the adverse effects of drought, but excessive accumulation of this metal in plants can be harmful. The suppressor of MAX2 1-like (SMXL) gene family, which plays important roles in various plant processes, including stress responses, remains poorly understood in common bean. In this study, we identified nine orthologues of SMXL genes in common bean, which are located on six chromosomes and classified into four subgroups. Basic molecular properties, including theoretical isoelectric point (PI), molecular weight (MW), grand average of hydropathicity (GVIO), gene structure, and conserved motifs were characterized, and numerous cis-elements in promoters were predicted. The expression patterns of PvSMXL genes were found to be distinct under 10% polyethylene glycol (PEG)-induced drought stress and 200 µM Cu treatments. Most PvSMXLs showed reduced expression in response to Cu treatment, whereas nearly half PvSMXLs exhibited inducible expression under drought stress. PvSMXL2, which exhibited a rapid response to karrikin 1 (KAR1), an active form of the plant growth regulators newly found in the smoke of burning plant material, was down-regulated by both PEG-induced drought and Cu stresses. Transient silencing of PvSMXL2 resulted in enhanced drought stress tolerance without conferring Cu tolerance. These findings provide valuable insights into the functions of SMXL genes in common bean under abiotic stress conditions.

Understanding water conservation vs. profligation traits in vegetable legumes through a physio-transcriptomic-functional approach.

Vegetable soybean and cowpea are related warm-season legumes showing contrasting leaf water use behaviors under similar root drought stresses, whose mechanisms are not well understood. Here we conducted an integrative phenomic-transcriptomic study on the two crops grown in a feedback irrigation system that enabled precise control of soil water contents. Continuous transpiration rate monitoring demonstrated that cowpea used water more conservatively under earlier soil drought stages, but tended to maintain higher transpiration under prolonged drought. Interestingly, we observed a soybean-specific transpiration rate increase accompanied by phase shift under moderate soil drought. Time-series transcriptomic analysis suggested a dehydration avoidance mechanism of cowpea at early soil drought stage, in which the VuHAI3 and VuTIP2;3 genes were suggested to be involved. Multifactorial gene clustering analysis revealed different responsiveness of genes to drought, time of day and their interactions between the two crops, which involved species-dependent regulation of the circadian clock genes. Gene network analysis identified two co-expression modules each associated with transpiration rate in cowpea and soybean, including a pair of negatively correlated modules between species. Module hub genes, including the ABA-degrading gene GmCYP707A4 and the trehalose-phosphatase/synthase gene VuTPS9 were identified. Inter-modular network analysis revealed putative co-players of the hub genes. Transgenic analyses verified the role of VuTPS9 in regulating transpiration rate under osmotic stresses. These findings propose that species-specific transcriptomic reprograming in leaves of the two crops suffering similar soil drought was not only a result of the different drought resistance level, but a cause of it.

Transcriptome Dynamics of Common Bean Roots Exposed to Various Heavy Metals Reveal Valuable Target Genes and Promoters for Genetic Engineering.

Understanding the gene regulatory basis of plant response to heavy metals (HMs) is fundamental for the management of food safety and security. However, a comprehensive and comparative view of the plant responses to different HMs is still lacking. Here, we compared root transcriptomes in common bean under 9 HM treatments at 50 µM for three time points each. Cd, Cr, Co, Ni, and Pb caused most severe morphological and/or biochemical retardations. A total of 448 genes were found to be responsive to all nine HMs, which were mostly involved in photosynthesis, oxidization-reduction, and ion binding. Cd and Cu triggered the greatest number of unique differentially expressed genes (DEG)s, which were predominantly related to cellular transport/localization in the former and RNA binding in the latter. Short-term and prolonged HM treatments shaped very different DEG patterns. Weighted gene co-expression network analysis identified six co-expression modules showing exceptionally high transcripts abundance in specific HM × time scenarios. We experimentally verified the promoter activity of the gene GIP1 and the novel function of XTH23 under Cu/Cd stress. Collectively, the transcriptomic atlas provides valuable resources for better understanding the common and unique mechanisms of plant response to different HMs and offers a mass of candidate target genes/promoters for genetic engineering.

Bicalutamide, an androgen receptor antagonist, effectively alleviate allergic rhinitis via suppression of PI3K-PKB activity.

OBJECTIVES: To investigate the therapeutic effect of Bicalutamide, an androgen receptor antagonist on the onset and development of allergic rhinitis in an animal model. METHODS: 40 male BALB/c mice were randomly divided into five groups (eight mice per group). Aluminum hydroxide powder was used as an adjuvant, combined with Ovalbumin (OVA) to establish the mouse model of allergic rhinitis via ultrasonic nebulization of OVA to stimulate the nasal cavity. Mice in Bica#1 group were intraperitoneally injected with 0.02 mg Bicalutamide/0.5 ml of normal saline daily for 7 consecutive days; mice in Bica#2 group were administered 0.02 mg Bicalutamide/0.5 ml of normal saline via intraperitoneal injection for 5 consecutive days, and then the same amount of normal saline was injected intraperitoneally for 2 consecutive days. Enzyme-linked immunosorbent assay was adopted to detect the serological levels of IgE, IL-4, and IL-6 production. Eosinophil infiltration was observed under microscope after hematoxylin and eosin staining of nasal mucosa. Quantitative PCR and Western blot were employed for determination of histamine receptors mRNA expression and PI3K/PKB associated protein levels, respectively. RESULTS: Histological analysis shown that allergic lesion was induced after OVA sensitization. Intraperitoneal injection with 0.02 mg Bicalutamide daily for 7 consecutive days significantly reduced the allergic lesion; however, mice injected with the same amount of normal saline at the same time demonstrated no allergic rhinitis symptoms. In addition, there was a significant reduction in eosinophils number in Bicalutamide treated mice (n = 8) compared to the OVA group (n = 8) (OVA: 19.6 ± 5.3 vs. Bica#1: 7.7 ± 0.8 vs. Bica#2: 9.4 ± 1.2, both p < 0.01). Furthermore, ELISA results revealed that the serological levels of IgE (OVA: 17.3 ± 1.7 µg/ml vs. Bica#1: 9.2 ± 0.6 vs. Bica#2: 10.4 ± 2.3, both p < 0.05), IL-4 (OVA: 164.3 ± 5.1 pg/ml vs. Bica#1: 110.2 ± 3.1 vs. Bica#2: 115.3 ± 4.1, both p < 0.05) and IL-6 (OVA: 167.3 ± 3.7 pg/ml vs. Bica#1: 117.5 ± 6.5 vs. Bica#2: 114.8 ± 2.4, both p < 0.05) were significantly decreased after two different dosage of Bicalutamide treatment. Similarly, histamine receptors in mast cells were significantly reduced after two different dosage of Bicalutamide treatment. More importantly, p-PKB protein was notably reduced after two different dosage of Bicalutamide treatment compared to the OVA group, mTOR protein levels were also down regulated after two different dosage of Bicalutamide treatment. CONCLUSIONS: Our data demonstrated that androgen receptor antagonist Bicalutamide can significantly alleviate allergic rhinitis lesion in the animal model. PI3K/PKB activity in mast cells was suppressed after Bicalutamide injection. Our results provide important implication in allergic rhinitis prevention and treatment.

The spatial pattern and influencing factors of tourism eco-efficiency in Inner Mongolia, China.

Background: Tourism eco-efficiency is a performance basis for evaluating green total factor productivity and sustainable development. Objective: The objective of this study was to measure tourism eco-efficiency in Inner Mongolia and explore its influencing factors. The aim was to provide an accurate reference for improving the quality and efficiency of tourism in Inner Mongolia and promoting the sustainable development of the regional economy and society. Methods: Tourism eco-efficiency in Inner Mongolia from 2009 to 2019 was calculated using a super-slacks-based measure (SBM) model with an undesirable output. The spatial variation function was used to explore the spatial evolution pattern of tourism eco-efficiency in Inner Mongolia, and the influencing factors of the spatial evolution were analyzed by geographically weighted regression. Results: Tourism eco-efficiency in Inner Mongolia is relatively low. Eco-efficiency values among cities in Inner Mongolia vary, and their distribution is not balanced. The structural eco-efficiency of tourism in Inner Mongolia has been consistent from 2009 to 2019. The degree of homogenization in the overall direction is relatively good. Furthermore, its spatial distribution form and internal structure evolution show a certain regularity and continuity. The pattern evolution of tourism eco-efficiency in Inner Mongolia is jointly driven by the economic level, environmental regulation, industrial structure, traffic conditions, resource endowment, and tourism reception facilities. These influencing factors show obvious spatial heterogeneity. Conclusion: From the perspective of Inner Mongolia, the difference in the tourism eco-efficiency value from 2009 to 2019 was relatively large, but the number of effective areas in the efficiency frontier generally showed a fluctuating growth trend. The range parameters of tourism eco-efficiency showed a decreasing trend, and the spatial correlation effect of tourism eco-efficiency in Inner Mongolia showed a decreasing trend under the influence of structural and spatial differentiation.

The Anatomical Basis of Heavy Metal Responses in Legumes and Their Impact on Plant-Rhizosphere Interactions.

Rapid industrialization, urbanization, and mine tailings runoff are the main sources of heavy metal contamination of agricultural land, which has become one of the major constraints to crop growth and productivity. Finding appropriate solutions to protect plants and agricultural land from heavy metal pollution/harmful effects is important for sustainable development. Phytoremediation and plant growth-promoting rhizobacteria (PGPR) are promising methods for this purpose, which both heavily rely on an appropriate understanding of the anatomical structure of plants. Specialized anatomical features, such as those of epidermis and endodermis and changes in the root vascular tissue, are often associated with heavy metal tolerance in legumes. This review emphasizes the uptake and transport of heavy metals by legume plants that can be used to enhance soil detoxification by phytoremediation processes. Moreover, the review also focuses on the role of rhizospheric organisms in the facilitation of heavy metal uptake, the various mechanisms of enhancing the availability of heavy metals in the rhizosphere, the genetic diversity, and the microbial genera involved in these processes. The information presented here can be exploited for improving the growth and productivity of legume plants in metal-prone soils.

First report of bean common mosaic virus naturally infecting yam bean (Pachyrhizus erosus) in China.

Yam bean (Pachyrhizus erosus), a high-yielding leguminous root crop with good nutritional value, is widely cultivated in southern China. In 2020, P. erosus (cv. Mumashan) plants exhibiting irregular yellow leaves and malformed seed pods (Supplementary Fig S1) were observed at Ningbo city, Zhejiang Province, China. To determine the causal agent(s) of the disease, symptomatic leaves (n=4) were collected for electron microscopy negative staining. Virus particles with a length of about 700nm, similar to viruses in the genus Potyvirus, were observed via transmission electron microscope (TEM), suggesting the presence a potyvirus(es). To further confirm which potyvirus(es) infected yam bean, total RNA was extracted from leaf samples of a total of six plants, including four symptomatic plants and two asymptomatic plants using TRIzol reagent (Invitrogen Carlsbad, CA, USA) according to the manufacturer's instructions. RNA was reverse-transcribed into cDNA with M4-T as the 3'-anchoring primer by ReverTra Ace® kit (Toyobo, Japan). Sprimer/M4 Potyviridae specific primers (Chen et al., 2001) were used for PCR analysis. A ~1,700-bp-long product was amplified from four symptomatic plants using KOD FX enzyme (Toyobo, Japan). No such band was amplified from the two asymptomatic plants. The PCR product (~1.7kb) amplified from a single symptomatic plant was ligated into the pEASY®-Blunt Zero vector (TransGen Bio, Beijing, China) and sequenced (Sangon Bio, Shanghai, China). The amplicon showed 99% nucleotide sequence identities with bean common mosaic virus (BCMV) isolate NKY021 (KJ807819). Subsequently, the complete nucleotide sequences of this BCMV isolate (referred as BCMV-NB) was amplified by overlapping RT-PCR and rapid amplification of cDNA ends with primers (Supplementary Table S1) designed from the sequence of BCMV isolate NKY021. The BCMV-NB full genome (Accession No. OL871237) consists of 10,053 nucleotides excluding the poly(A) tail and contains a large open reading frame encoding a polyprotein of 3222 amino acids. BLASTn analysis showed that BCMV-NB shared a sequence identity of 96.4% with BCMV isolate HZZB011 (KJ807815). Phylogenetic tree generated by Neighbour-Joining method revealing the BCMV-NB isolate was grouped together with Chinese isolates from Glycine max (Supplementary Fig S1). To test the infectivity of BCMV-NB, virus-free yam bean (cv. Mumashan) and Nicotiana benthamiana seedlings were mechanically inoculated with sap extracted from the symptomatic leaves of a BCMV-NB-infected yam bean plant. The inoculated yam bean plants developed typical BCMV mosaic and chlorotic symptoms at 16 days post inoculation (dpi), while Nicotiana benthamiana had no obvious symptoms at 10 or 20 dpi (Supplementary Fig S1). BCMV infections were confirmed in yam bean plants (infection rate 6/6) and N. benthamiana plants (infection rate 8/8) by RT-PCR at 16 dpi and 10 dpi, respectively. Twelve further P. erosus plants (cv. Mumashan) were collected from a field in Ningbo city and tested by RT-PCR with BCMV-specific primer pair BCMV CP (+)/(-) (Supplementary Table 1). Eight out of the 12 samples tested positive for BCMV by PCR-gel electrophoresis (Supplementary Fig S1) and Sanger sequencing, suggesting a high incidence of BCMV infection in this field. BCMV infection in yam bean has been reported from Indonesia (Damayanti et al., 2008) and Peru (Fuentes et al., 2012). To the best of our knowledge, this is the first report of BCMV naturally infecting yam bean in China. Thus, special attention and appropriate management strategies are needed to minimize the damage caused by BCMV to yam bean crops in China.

LY294002 attenuates inflammatory response in endotoxin-induced uveitis by downregulating JAK3 and inactivating the PI3K/Akt signaling.

CONTEXT: Uveitis is a prevalent inflammatory eye disease that damages the vision of patients and even leads to blindness. LY294002, an inhibitor of PI3K, was reported to suppress the inflammation and alleviate the progression of many diseases. However, the function of LY294002 in uveitis is unclear. OBJECTIVE: This study aimed to explore the function of LY294002 in endotoxin-induced uveitis (EIU). MATERIALS AND METHODS: EIU rat models were established via a single intravitreal injection of LPS. At 24 h after LPS injection, the rats received LY294002 treatment for 14 days. The histopathology was observed by H&E staining. The concentration of proinflammatory cytokines in aqueous humor was tested by ELISA. The expression of proinflammatory cytokines in the iris ciliary body (ICB) and retina of EIU rats were detected by RT-qPCR. JAK3, PI3K, and Akt expression were assessed by RT-qPCR and western blotting. Translocation of Akt in rat retinal Müller cells (rMC-1) was evaluated by immunofluorescence staining. RESULTS: LY294002 alleviated ocular inflammation and decreased inflammatory cell infiltration in the anterior chamber, iris, ciliary body, vitreous cavity, and retina of EIU rats. LY294002 decreased the concentration of proinflammatory cytokines INF-γ, IL-17, IL-6, TNF-α, and IL-1ß in aqueous humor and their expression in the ICB and retina of EIU rats. LY294002 downregulated JAK3 expression in EIU rats. LY294002 inhibited p-PI3K and p-Akt expression in EIU rats and restrained Akt translocation from cytoplasm to cell membrane in LPS-treated rMC-1 cells. CONCLUSION: LY294002 ameliorates inflammation in EIU by downregulating JAK3 and inactivating the PI3K/Akt signaling.

Research Progress of MEMS Inertial Switches.

As a typical type of MEMS acceleration sensor, the inertial switch can alter its on-off state while the environmental accelerations satisfy threshold value. An exhaustive summary of the design concept, performance aspects, and fabrication methods of the micro electromechanical system (MEMS) inertial switch is provided. Different MEMS inertial switch studies were reviewed that emphasized acceleration directional and threshold sensitivity, contact characteristics, and their superiorities and disadvantages. Furthermore, the specific fabrication methods offer an applicability reference for the preparation process for the designed inertial switch, including non-silicon surface micromachining technology, standard silicon micromachining technology, and the special fabrication method for the liquid inertial switch. At the end, the main conclusions of the current challenges and prospects about MEMS inertial switches are drawn to assist with the development of research in the field of future engineering applications.

A social network analysis of tourism cooperation in the Yangtze River Delta: A supply and demand perspective.

This study explores the spatial structure of regional tourism cooperation networks among 27 cities in the Yangtze River Delta from the perspective of supply and demand. Data from the supply network were collected from official news released by the Chinese government and quotations for tour routes published by travel agencies. Travel notes published on tourists' blog community platforms about their travel experiences were used as source data for the demand network. The degree of cooperation between the cities was analyzed based on the frequency of occurrence and co-occurrence of information on tourist attractions or cities in the Yangtze River Delta region in tourist notes, tourist route quotes, and official news. This study divides 27 cities in the Yangtze River Delta region into three categories: those where supply matches demand (e.g., Shanghai and Nanjing), nine cities where there is a demand lag (e.g., Zhenjiang), and 16 cities where there is a supply lag (e.g., Wuxi). Investigating the differences between the supply and demand networks is helpful to understand the effectiveness of regional tourism cooperation mechanisms and government policies, which is crucial for the sustainability and good governance of regional tourism.

Turnip mosaic virus P1 suppresses JA biosynthesis by degrading cpSRP54 that delivers AOCs onto the thylakoid membrane to facilitate viral infection.

Jasmonic acid (JA) is a crucial hormone in plant antiviral immunity. Increasing evidence shows that viruses counter this host immune response by interfering with JA biosynthesis and signaling. However, the mechanism by which viruses affect JA biosynthesis is still largely unexplored. Here, we show that a highly conserved chloroplast protein cpSRP54 was downregulated in Nicotiana benthamiana infected by turnip mosaic virus (TuMV). Its silencing facilitated TuMV infection. Furthermore, cpSRP54 interacted with allene oxide cyclases (AOCs), key JA biosynthesis enzymes, and was responsible for delivering AOCs onto the thylakoid membrane (TM). Interestingly, TuMV P1 protein interacted with cpSRP54 and mediated its degradation via the 26S proteosome and autophagy pathways. The results suggest that TuMV has evolved a strategy, through the inhibition of cpSRP54 and its delivery of AOCs to the TM, to suppress JA biosynthesis and enhance viral infection. Interaction between cpSRP54 and AOCs was shown to be conserved in Arabidopsis and rice, while cpSRP54 also interacted with, and was degraded by, pepper mild mottle virus (PMMoV) 126 kDa protein and potato virus X (PVX) p25 protein, indicating that suppression of cpSRP54 may be a common mechanism used by viruses to counter the antiviral JA pathway.

Complete genome sequence of a putative novel ilarvirus isolated from Eleocharis dulcis.

The complete genomic sequence of a novel ilarvirus from Eleocharis dulcis, tentatively named "water chestnut virus A" (WCVA), was determined using next-generation sequencing (NGS) combined with reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) PCR. The three genomic RNA components of WCVA were 3578 (RNA1), 2873 (RNA2), and 2073 (RNA3) nucleotides long, with four predicted open reading frames containing conserved domains and motifs typical of ilarviruses. Phylogenetic analysis of each predicted protein consistently placed WCVA in subgroup 4 of the genus Ilarvirus, together with prune dwarf virus, viola white distortion associated virus, Fragaria chiloensis latent virus, and potato yellowing virus. The genetic distances and lack of serological reaction to antisera against other ilarviruses suggest that WCVA is a novel member of the genus.

Genome-Wide Identification and Expression Profiling of the BZR Transcription Factor Gene Family in Nicotiana benthamiana.

Brassinazole-resistant (BZR) family genes encode plant-specific transcription factors (TFs), play essential roles in the regulation of plant growth and development, and have multiple stress-resistance functions. Nicotiana benthamiana is a model plant widely used in basic research. However, members of the BZR family in N. benthamiana have not been identified, and little is known about their function in abiotic stress. In this study, a total of 14 BZR members were identified in the N. benthamiana genome, which could be divided into four groups according to a phylogenetic tree. NbBZRs have similar exon-intron structures and conserved motifs, and may be regulated by cis-acting elements such as STRE, TCA, and ARE, etc. Organ-specific expression analysis showed that NbBZR members have different and diverse expression patterns in different tissues, and most of the members are expressed in roots, stems, and leaves. The analysis of the expression patterns in response to different abiotic stresses showed that all the tested NbBZR members showed a significant down-regulation after drought treatment. Many NbBZR genes also responded in various ways to cold, heat and salt stress treatments. The results imply that NbBZRs have multiple functions related to stress resistance.

Genome-wide identification and analysis of Catharanthus roseus RLK1-like kinases in Nicotiana benthamiana.

BACKGROUND: The Catharanthus roseus RLK1-like kinase (CrRLK1L) is a subfamily of the RLK gene family, and members are sensors of cell wall integrity and regulators of cell polarity growth. Recent studies have also shown that members of this subfamily are involved in plant immunity. Nicotiana benthamiana is a model plant widely used in the study of plant-pathogen interactions. However, the members of the NbCrRLK1L subfamily and their response to pathogens have not been reported. RESULTS: In this study, a total of 31 CrRLK1L members were identified in the N. benthamiana genome, and these can be divided into 6 phylogenetic groups (I-VI). The members in each group have similar exon-intron structures and conserved motifs. NbCrRLK1Ls were predicted to be regulated by cis-acting elements such as STRE, TCA, ABRE, etc., and to be the target of transcription factors such as Dof and MYB. The expression profiles of the 16 selected NbCrRLK1Ls were determined by quantitative PCR. Most NbCrRLK1Ls were highly expressed in leaves but there were different and diverse expression patterns in other tissues. Inoculation with the bacterium Pseudomonas syringae or with Turnip mosaic virus significantly altered the transcript levels of the tested genes, suggesting that NbCrRLK1Ls may be involved in the response to pathogens. CONCLUSIONS: This study systematically identified the CrRLK1L members in N. benthamiana, and analyzed their tissue-specific expression and gene expression profiles in response to different pathogens and two pathogens associated molecular patterns (PAMPs). This research lays the foundation for exploring the function of NbCrRLK1Ls in plant-microbe interactions.