Transcriptome analysis revealed molecular basis of cold response in Prunus mume.

Japanese apricot (Prunus mume Sieb. et Zucc.) is a traditional woody flower and fruit tree restrictedly cultivated in northern area due to its inability to survive harsh winters and early springs. In the current study, RNA-seq and physiological assay were used to study the cold response of P. mume 'Xuemei'. A total of 4705 genes were identified as differentially expressed genes (DEGs) in the 21 pairwise comparisons among seven time points under 0 °C cold treatment, and 3678 of them showed differential levels compared with control at normal temperature. The gene expression profiles indicated that the number of upregulated genes increased with prolongation of treatment time throughout the whole 48 h. Hierarchical clustering suggested three obvious phases of the gene expression profiles. Gene ontology (GO) analysis of the 4705 DEGs resulted in 102 significantly enriched GO items in which the transcription activity was dominant. 225 DEGs were predicted to encode transcription factor (TF) genes. Some important TFs (ERF, CBF, WRKY, NAC, MYB, bHLH) were strongly induced during the whole cold treatment. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis suggested that plant signal transduction pathways such as plant hormone and calcium (Ca2+) were notable. Metabolic pathways such as sugar metabolism, especially RFOs (raffinose family oligosaccharides) were activated, which was accompanied by the accumulation of soluble sugars. SOD and POD enzyme activities coupled with reactive oxygen species (ROS)-related gene expression profile implied a gradually induced ROS scavenging system under cold treatment. These results might shed light on the sensitivity to cold stress in Japanese apricot and provide new insights into hardiness studies in P. mume and its related species. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01376-2.

Identification of the DcHsp20 gene family in carnation (Dianthus caryophyllus) and functional characterization of DcHsp17.8 in heat tolerance.

MAIN CONCLUSION: 33 heat shock protein 20 (Hsp20) genes were identified from the carnation genome whose expression were altered by abiotic stresses. DcHsp17.8 may function to improve the heat resistance of Arabidopsis. Heat shock proteins 20 (Hsp20s) mainly function as molecular chaperones that play crucial roles in relieving abiotic stresses such as heat stress. In this study, we identified and characterized 33 DcHsp20 genes from the carnation genome that were classified into 9 subfamilies. Gene structure analysis showed that 25 DcHsp20 genes contained 1 intron whilst the remaining 8 DcHsp20 genes did not contain introns. Motif analysis found that DcHsp20 proteins were relatively conserved. Cis-regulatory elements analysis of the Hsp20 promoters revealed a number of cis-regulatory elements that regulate growth and development, hormone and stress responses. Gene expression analysis revealed that DcHsp20 genes had multiple response patterns to heat stress. The largest range of induction occurred in DcHsp17.8 after 1 h of heat stress. Under cold stress, or treatment with saline or abscisic acid, the expression of most DcHsp20 genes was inhibited. To further understand the function of DcHsp20 genes in response to heat stress, we overexpressed DcHsp17.8 in Arabidopis and the plants showed improved heat tolerance, O2- and H2O2 activities and photosynthetic capacity with reduced relative electrolyte leakage and malondialdehyde content. Gene expression analysis revealed that DcHsp17.8 modulated the expression of genes involved in antioxidant enzyme synthesis. Our data provided a solid foundation for the further detailed study of DcHsp20 genes.

Genome-Wide Identification, Classification, and Expression Analysis of the Hsf Gene Family in Carnation (Dianthus caryophyllus).

Heat shock transcription factors (Hsfs) are a class of important transcription factors (TFs) which play crucial roles in the protection of plants from damages caused by various abiotic stresses. The present study aimed to characterize the Hsf genes in carnation (Dianthus caryophyllus), which is one of the four largest cut flowers worldwide. In this study, a total of 17 non-redundant Hsf genes were identified from the D. caryophyllus genome. Specifically, the gene structure and motifs of each DcaHsf were comprehensively analyzed. Phylogenetic analysis of the DcaHsf family distinctly separated nine class A, seven class B, and one class C Hsf genes. Additionally, promoter analysis indicated that the DcaHsf promoters included various cis-acting elements that were related to stress, hormones, as well as development processes. In addition, cis-elements, such as STRE, MYB, and ABRE binding sites, were identified in the promoters of most DcaHsf genes. According to qRT-PCR data, the expression of DcaHsfs varied in eight tissues and six flowering stages and among different DcaHsfs, even in the same class. Moreover, DcaHsf-A1, A2a, A9a, B2a, B3a revealed their putative involvement in the early flowering stages. The time-course expression profile of DcaHsf during stress responses illustrated that all the DcaHsfs were heat- and drought-responsive, and almost all DcaHsfs were down-regulated by cold, salt, and abscisic acid (ABA) stress. Meanwhile, DcaHsf-A3, A7, A9a, A9b, B3a were primarily up-regulated at an early stage in response to salicylic acid (SA). This study provides an overview of the Hsf gene family in D. caryophyllus and a basis for the breeding of stress-resistant carnation.

Genome-wide characterization of DcHsp90 gene family in carnation (Dianthus caryophyllus L.) and functional analysis of DcHsp90-6 in heat tolerance.

Plant heat shock protein 90 (Hsp90) participates in various physiological processes including protein folding, degradation, and signal transduction. However, the DcHsp90 gene family in carnation (Dianthus caryophyllus L.) has not been systematically analyzed. We thoroughly examined and comprehensively analyzed the carnation DcHsp90 gene family in this study and discovered 9 DcHsp90 genes. Based on the phylogenetic examination, DcHsp90 proteins may be divided into two groups. DcHsp90 structural features were similar but varied between groups. Promoter analysis revealed the presence of many cis-acting elements, most of which were connected to growth and development, hormones, and stress. DcHsp90 genes may play distinct functions in heat stress response, according to gene expression analyses. The DcHsp90-6 was isolated, and its role in the reaction to heat stress was studied. Thermotolerance and superoxide dismutase activity in transgenic seedlings were enhanced by Arabidopsis overexpression of DcHsp90-6. After heat stress, transgenic plants' electrolyte leakage and malondialdehyde levels were much lower than wild-type plants. Furthermore, overexpression of DcHsp90-6 altered the expressions of stress-responsive genes such as AtHsp101, AtHsp90, AtGolS1, AtRS4/5, and AtHsfB1. This study provides comprehensive information on the DcHsp90 gene family and suggests that overexpressed DcHsp90-6 positively regulates thermotolerance highlighting the adaptation mechanism of carnation under heat stress.

Exogenous melatonin ameliorates heat damages by regulating growth, photosynthetic efficiency and leaf ultrastructure of carnation.

Carnation (Dianthus caryophyllus L.) is a floral crop that is highly valuable commercially. However, high temperatures adversely affect its growth and the quality of its cut flowers. Melatonin (MT) is a indole substance that can mitigate plant damage under heat stress. In this study, the leaves of carnation seedlings were sprayed with different concentrations of MT before exposure to high temperature. The indices of growth, physiological and chlorophyll fluorescence were measured and analyzed by the membership function method. The results showed that treatment with 100 µM MT was the most effective at ameliorating damage on carnation. We then analyzed the effects of 100 µM MT pretreatment on carnation at different time points of heat stress and found that this concentration of MT ameliorated the damage caused by heat stress, increased the content of photosynthetic pigments, enhanced the performance of photosystem II and improved photosynthesis. In addition, MT also reduced cell damage and lipid peroxidation, increased the activities of antioxidant enzymes and regulated the accumulation of osmotic substances in carnation. Moreover, MT increased the fresh/dry weight of stems and roots, promoted the opening of stomata, and protected the integrity of chloroplast structure of carnation. Compared with heat stress, pre-spraying with MT significantly down-regulated the transcription of a chlorophyll degradation gene and up-regulated the transcription of stress-related genes. Overall, this study provides a theoretical foundation for the mitigation of the adverse effects of exogenous MT under heat stress and proposes beneficial implications for the management of other plants subjected to global warming.

Emergence agitation after the cleft lip or palate surgery in pediatric patients: a prospective study.

OBJECTIVE: The pediatric patients after the cleft lip or palate surgery have high incidences of postoperative complications. Emergence agitation is a common complication. It is also a mild complication compared with lingual swelling and other airway-related complications, which are more often expected in children. However, it can cover signs of hypoxic episodes that appear immediately after surgery, because enough monitoring of an agitated child is not possible. The study aimed to discuss the occurrence of EA after cleft lip or palate surgery in pediatric patients, and further to provide a basis for later interventions. METHODS: This prospective study included 214 patients aged 3 months to 6 years old at a tertiary stomatological teaching hospital. We calculated the EA scores for every patient when they entered PACU, were in PACU, and left from PACU, and the score ranges from 1 to 5 point. The patients occurred agitation if they scored from 3 to 5 on the 5-point scale, and the patients needed medication and care if they had a score of 4 or 5. RESULT: The results showed that the EA scores of 69.63% (n = 149) among patients were 3 or higher when they entered PACU, 40.65% (n = 87) were 3 or higher when they were in PACU, and 21.03% (n = 45) were 3 or higher when they left from PACU. Whether they are children with cleft lip, cleft palate, or horizontal cleft, the EA scores had a significant difference among different timings when entering PACU, in PACU, and leaving PACU (P = 0.000). Further comparison showed that the EA score of patients was the highest when entering PACU, and the lowest when leaving PACU. A significant difference in the EA scores was found among the patients with cleft lip, cleft palate, and horizontal cleft when they were in PACU (P = 0.024), further comparison showed that the EA score of the patients with cleft lip was lower than patients with cleft palate or horizontal cleft. While there were no statistical differences in the EA scores among the patients with cleft lip, cleft palate, and horizontal cleft when they entered PACU and left from PACU (P > 0.05). CONCLUSION: Children had a high incidence of EA after cleft lip or cleft palate or horizontal cleft surgery, especially when they entered PACU. Children after cleft palate and horizontal cleft surgery had higher incidences of EA than cleft lip surgery when they were in PACU.

Genome-wide identification and classification of the Hsf and sHsp gene families in Prunus mume, and transcriptional analysis under heat stress.

The transcriptional activation of heat shock proteins (Hsps) by heat shock transcription factors (Hsfs) is presumed to have a pivotal role in plant heat stress (HS) response. Prunus mume is an ornamental woody plant with distinctive features, including rich varieties and colors. In this study, 18 Hsfs and 24 small Hsps (sHsps) were identified in P. mume. Their chromosomal locations, protein domains, conserved motifs, phylogenetic relationships, and exon-intron structures were analyzed and compared with Arabidopsis thaliana Hsfs or sHsps. A total of 18 PmHsf members were classified into three major classes, A, B, and C. A total of 24 PmsHsps were grouped into eight subfamilies (CI to CIII, P, endoplasmic reticulum, M, and CI- or P-related). Quantitative reverse transcription PCR analysis revealed that members of the A2, A7, and A9 groups became the prominent Hsfs after heat shock, suggesting their involvement in a key regulatory role of heat tolerance. Most of the PmsHsp genes were up-regulated upon exposure to HS. Overall, our data contribute to an improved understanding of the complexity of the P. mume Hsf and sHsp gene families, and provide a basis for directing future systematic studies investigating the roles of the Hsf and sHsp gene families.

Hyaluronic Acid-Functionalized Gold Nanorods with pH/NIR Dual-Responsive Drug Release for Synergetic Targeted Photothermal Chemotherapy of Breast Cancer.

Tumor-targeted delivery of photothermal agent and controlled release of concomitant chemotherapeutic drug are two key factors for combined photothermal chemotherapy. Herein, we developed a pH/near-infrared (NIR) dual-triggered drug release nanoplatform based on hyaluronic acid (HA)-functionalized gold nanorods (GNRs) for actively targeted synergetic photothermal chemotherapy of breast cancer. Targeting folate (FA), dopamine, and adipic acid dihydrazide triconjugated HA was first synthesized and used to decorate GNRs via Au-catechol bonds, and then an anticarcinogen doxorubicin (DOX) was conjugated onto HA moieties via an acid-labile hydrazone linkage, resulting in multifunctional nanoparticles GNRs-HA-FA-DOX. The nanoparticles exhibited excellent stability and had a pH and NIR dual-responsive drug release behavior. In vitro studies showed that the nanoparticles could be efficiently internalized into breast cancer MCF-7 cells and kill them under NIR irradiation in a synergistic fashion via inducing cell apoptosis. Pharmacokinetics and biodistribution studies in tumor-bearing mice indicated that the nanoparticles had a long blood circulation with a half-life of 2.4 h and exhibited a high accumulation of 11.3% in tumor site. The tumors of mice treated with combined chemotherapy and photothermal therapy were completely suppressed without obvious systemic toxicity after 20 d of treatment. These results demonstrated a great potential of GNRs-HA-FA-DOX nanoparticles for targeted synergistic therapy of breast cancer.