CRISPR/Cas9 edited SlGT30 improved both drought resistance and fruit yield through endoreduplication.

There is often a trade-off effect between different agronomic traits due to gene pleiotropy, leading to a negative correlation between yield and resistance. Consequently, using gene-editing techniques to develop superior traits becomes challenging. Genetic resources that defy this constraint are scarce but hold great potential as targets for improvement through the utilisation of CRISPR. Transcription factors are critical in modulating numerous gene expressions across diverse biological processes. Here, we found that the trihelix transcription factor SlGT30 plays a role in drought resistance and tomato fruit development. We edited the SlGT30 gene with CRISPR/Cas9 technology and found that the knockout lines showed decreased stomata density in the leaves and large fruits. Subsequent examination revealed that cell ploidy was impacted in the leaves and fruits of SlGT30 knockout lines. SlGT30 knockout affected cell size through the endoreduplication pathway, manifested in decreased stomata density and reduced water loss. Consequently, this resulted in an enhancement of drought resistance. For the fruit, both cell size and cell number increased in the fruit pericarp of knockout lines, improving the fruit size and weight accordingly. Therefore, SlGT30 represents a promising candidate gene for gene editing in breeding practice.

SlMYC2 promotes SlLBD40-mediated cell expansion in tomato fruit development.

As a plant-specific transcription factor, lateral organ boundaries domain (LBD) protein was reported to regulate plant growth and stress response, but the functional research of subfamily II genes is limited. SlMYC2, a master regulator of Jasmonic acid response, has been found to exhibit high expression levels in fruit and has been implicated in the regulation of fruit ripening and resistance to Botrytis. However, its role in fruit expansion remains unknown. In this study, we present evidence that a subfamily II member of LBD, namely SlLBD40, collaborates with SlMYC2 in the regulation of fruit expansion. Overexpression of SlLBD40 significantly promoted fruit growth by promoting mesocarp cell expansion, while knockout of SlLBD40 showed the opposite result. Similarly, SlMYC2 knockout resulted in a significant decrease in cell expansion within the fruit. Genetic analysis indicated that SlLBD40-mediated cell expansion depends on the expression of SlMYC2. SlLBD40 bound to the promoter of SlEXPA5, an expansin gene, but did not activate its expression directly. While, the co-expression of SlMYC2 and SlLBD40 significantly stimulated the activation of SlEXPA5, leading to an increase in fruit size. SlLBD40 interacted with SlMYC2 and enhanced the stability and abundance of SlMYC2. Furthermore, SlMYC2 directly targeted and activated the expression of SlLBD40, which is essential for SlLBD40-mediated fruit expansion. In summary, our research elucidates the role of the interaction between SlLBD40 and SlMYC2 in promoting cell expansion in tomato fruits, thus providing novel insights into the molecular genetics underlying fruit growth.

Anabolism and signaling pathways of phytomelatonin.

Phytomelatonin is a small multifunctional molecule found ubiquitously in plants, which plays an important role in plant growth, development, and biotic and abiotic stress responses. The classical biosynthetic and metabolic pathways of phytomelatonin have been elucidated, and uncovering alternative pathways has deepened our understanding of phytomelatonin synthesis. Phytomelatonin functions mainly via two pathways. In the direct pathway, phytomelatonin mediates the stress-induced reactive oxygen species burst through its strong antioxidant capacity. In the indirect pathway, phytomelatonin acts as a signal to activate signaling cascades and crosstalk with other plant hormones. The phytomelatonin receptor PMTR1/CAND2 was discovered in 2018, which enhanced our understanding of phytomelatonin function. This review summarizes the classical and potential pathways involved in phytomelatonin synthesis and metabolism. To elucidate the functions of phytomelatonin, we focus on the crosstalk between phytomelatonin and other phytohormones. We propose two models to explain how PMTR1 transmits the phytomelatonin signal through the G protein and MAPK cascade. This review will facilitate the identification of additional signaling molecules that function downstream of the phytomelatonin signaling pathway, thus improving our understanding of phytomelatonin signal transmission.

The jasmonate-induced bHLH gene SlJIG functions in terpene biosynthesis and resistance to insects and fungus.

Jasmonic acid (JA) is a key regulator of plant defense responses. Although the transcription factor MYC2, the master regulator of the JA signaling pathway, orchestrates a hierarchical transcriptional cascade that regulates the JA responses, only a few transcriptional regulators involved in this cascade have been described. Here, we identified the basic helix-loop-helix (bHLH) transcription factor gene in tomato (Solanum lycopersicum), METHYL JASMONATE (MeJA)-INDUCED GENE (SlJIG), the expression of which was strongly induced by MeJA treatment. Genetic and molecular biology experiments revealed that SlJIG is a direct target of MYC2. SlJIG knockout plants generated by gene editing had lower terpene contents than the wild type from the lower expression of TERPENE SYNTHASE (TPS) genes, rendering them more appealing to cotton bollworm (Helicoverpa armigera). Moreover, SlJIG knockouts exhibited weaker JA-mediated induction of TPSs, suggesting that SlJIG may participate in JA-induced terpene biosynthesis. Knocking out SlJIG also resulted in attenuated expression of JA-responsive defense genes, which may contribute to the observed lower resistance to cotton bollworm and to the fungus Botrytis cinerea. We conclude that SlJIG is a direct target of MYC2, forms a MYC2-SlJIG module, and functions in terpene biosynthesis and resistance against cotton bollworm and B. cinerea.

CircRNA PLOD2 enhances ovarian cancer propagation by controlling miR-378.

It has been confirmed that circular RNA participates in tumorgenesis through a variety of ways, so it may be used as a molecular marker for tumor diagnosis and treatment. In this study, the expression of circ-LOPD2 in ovarian cancer tissues and cell lines was detected by qRT-PCR and Western blot. The dual luciferase report was used to verify the target of circ-LOPD2, and the silencing and overexpression of circ-CSPP1 in cell lines was used to explore its relationship with miRNA-378. The cell proliferation was detected by CCK8 method, and the expression level of miRNA-378 was detected by qRT-PCR. The results showed that circ-LOPD2 was highly expressed in ovarian cancer (OC) tissues, circ-LOPD2 expression levels were higher in OVCAR3 and A2780, and circ-LOPD2 expression levels in CAOV3 were lower. After silencing circ-LOPD2, the growth ability of OVCAR3 and A2780 cells decreased, while overexpression of circ-LOPD2 led to the opposite result. We also found that miR-378 is a target of circ-LOPD2. Silencing circ-LOPD2 will increase the expression of miR-378, and overexpression of circ-LOPD2 will decrease the expression of miR-378. In summary, our results show that circ-LOPD2 as a miR-378 sponge promotes the proliferation of ovarian cancer cells, which may in turn promote the development of OC.

A tubby-like protein CsTLP8 acts in the ABA signaling pathway and negatively regulates osmotic stresses tolerance during seed germination.

BACKGROUND: TLPs (Tubby-like proteins) are widespread in eukaryotes and highly conserved in plants and animals. TLP is involved in many biological processes, such as growth, development, biotic and abiotic stress responses, while the underlying molecular mechanism remains largely unknown. In this paper we characterized the biological function of cucumber (Cucumis sativus L.) Tubby-like protein 8 (CsTLP8) in Arabidopsis. RESULTS: In cucumber, the expression of the tubby-like protein CsTLP8 was induced by NaCl treatment, but reduced by PEG (Polyethylene Glycol) and ABA (Abscisic Acid) treatment. Subcellular localization and transcriptional activation activity analysis revealed that CsTLP8 possessed two characteristics of classical transcription factors: nuclear localization and trans-activation activity. Yeast two-hybrid assay revealed interactions of CsTLP8 with CsSKP1a and CsSKP1c, suggesting that CsTLP8 might function as a subunit of E3 ubiquitin ligase. The growth activity of yeast with ectopically expressed CsTLP8 was lower than the control under NaCl and mannitol treatments. Under osmotic and salt stresses, overexpression of CsTLP8 inhibited seed germination and the growth of Arabidopsis seedlings, increased the content of MDA (Malondialdehyde), and decreased the activities of SOD (Superoxide Dismutase), POD (Peroxidase) and CAT (Catalase) in Arabidopsis seedlings. Overexpression of CsTLP8 also increased the sensitivity to ABA during seed germination and ABA-mediated stomatal closure. CONCLUSION: Under osmotic stress, CsTLP8 might inhibit seed germination and seedling growth by affecting antioxidant enzymes activities. CsTLP8 acts as a negative regulator in osmotic stress and its effects may be related to ABA.

Prognostic value of microRNA-378 in esophageal cancer and its regulatory effect on tumor progression.

The incidence and mortality rates of esophageal squamous cell carcinoma (ESCC) are high in China, which has increased the clinical and economic burden. The present study aimed to investigate the role of microRNA (miRNA/miR)-378 in ESCC. Reverse transcription-quantitative polymerase chain reaction analysis was performed to detect miR-378 expression in ESCC tissues and cell lines. Survival analysis was performed using the Kaplan-Meier method, while Cox regression analysis was performed to determine the prognostic value of miR-378 in ESCC. miR-378 mimic and miR-378 inhibitor was transfected into ESCC cells to overexpress or knockdown miR-378 expression levels in ESCC cells. The Cell Counting Kit-8 assay was performed to assess the proliferative ability of ESCC cells, while the Transwell assay was conducted to assess the effect of miR-378 on the migratory and invasive abilities of ESCC cells. The results demonstrated that miR-378 displayed significantly lower expression both in ESCC cells and tissues by comparison with those in normal cells and adjacent tissues. In addition, patients with low miR-378 expression had a worse prognosis and a shorter overall survival time than those with high miR-378 expression. Furthermore, low miR-378 expression promoted ESCC cell proliferation, migration and invasion. Taken together, the results of the present study suggest that miR-378 may act as a tumor suppressor in the occurrence and development of ESCC.

Enzymatic macrocyclization of ribosomally synthesized and posttranslational modified peptides via C-S and C-C bond formation.

Covering: 2000 to 2020 Ribosomally synthesized and posttranslational modified peptides (RiPPs) are a rapidly growing class of bioactive natural products. Many members of RiPPs contain macrocyclic structural units constructed by modification enzymes through macrocyclization of linear precursor peptides. In this study, we summarize recent progress in the macrocyclization of RiPPs by C-S and C-C bond formation with a focus on the current understanding of the enzymatic mechanisms.

Analysis of risk factors of diabetes peripheral neuropathy in type 2 diabetes mellitus and nursing intervention.

The aim of the present study was to explore the risk factors of diabetes peripheral neuropathy (DPN) in type 2 diabetes mellitus, and to propose corresponding nursing intervention measures to provide the basis for early diagnosis, treatment and prevention of DPN. A retrospective analysis was performed on 130 patients with type 2 diabetes mellitus (T2DM) in the communities surrounding our hospital from January 2017 to June 2018. They were divided into a DPN group (62 cases) and non-DPN group (control group, 68 cases). First, a univariate analysis was performed. DPN or non-DPN were used as dependent variables, and statistically significant parameters in univariate analysis were used as independent variables. Multivariate logistic regression analysis was included to analyze the peripheral nerves in type 2 diabetes mellitus. At the same time, the patients with DPN were given individualized comprehensive nursing intervention. Univariate analysis showed that body mass index (BMI), diabetes duration, smoking history, drinking history, family history of diabetes, fasting blood glucose (FBG), postprandial blood glucose (PBG), glycosylated hemoglobin (HbA1c), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), systolic blood pressure, 24-h urine microalbumin excretion (24hmALB), glomerular filtration rate (GFR), serum creatinine in DPN group were significantly different from those in the control group (P<0.05). Logistic regression analysis showed that the duration of diabetes, PBG, glycosylated hemoglobin (HbA1c), HDL-C, 24hmALB, and GFR were independent risk factors for DPN. The quality of life [Physiological function (PF), Role-physical (RP), Role-emotional (RE), General health (GH), Social function (SF), Mental health (MH), Bodily pain (BP), Vitality (VT)] in the DPN group was significantly improved after six months of individualized nursing intervention compared with that before intervention (P<0.05). In conclusion, the high risk factors of DPN should be identified as early as possible, to prevent and delay the occurrence and development of diabetes peripheral neuropathy, so as to improve the quality of life of these patients.

Melatonin promotes carotenoid biosynthesis in an ethylene-dependent manner in tomato fruits.

In tomato, red color is a key commercial trait and arises from the accumulation of carotenoids. Previous studies have revealed that melatonin promotes lycopene accumulation and ethylene production. However, it is unclear if melatonin similarly increases other carotenoids, and whether any increase of carotenoids in tomato fruit is directly related to ethylene production. In this study, changes in carotenoid profiles during fruit ripening were investigated in control (CK) and in fruits treated with melatonin (M50). The α, ß-carotene, and lycopene levels were significantly increased in M50, and there was increased carotenoid biosynthetic gene expression. We also observed up-regulated transcript levels of SlRIN, SlCNR, and SlNOR in M50 compared to CK. To better understand the regulation of carotenoid biosynthesis by melatonin and its potential response to endogenous ethylene, we tested an ethylene-insensitive mutant, Never ripe (Nr). Melatonin-treated Nr failed to accumulate more carotenoids compared to CK, although there was significantly changed ethylene production. Additionally, there was no general upregulation of expression of ripening-related genes in this mutant under melatonin treatment. These results suggest melatonin function might require ethylene to promote carotenoid synthesis in tomato.

SlSNAT Interacts with HSP40, a Molecular Chaperone, to Regulate Melatonin Biosynthesis and Promote Thermotolerance in Tomato.

The SNAT enzyme participates in the biosynthesis of melatonin, which is reported to regulate thermotolerance in many plants. However, the mechanistic basis of this regulation remains unclear. In this study, we identified the SlSNAT gene, which is responsible for melatonin biosynthesis in tomato. SlSNAT expression levels were 3- and 5-fold higher in SlSNAT overexpression lines OX-2 and OX-6, respectively. The melatonin levels were 3- and 4-fold higher than those in wild type. The melatonin levels decreased by 50% when the expression of SlSNAT was downregulated to 40%. Overexpression of SlSNAT in tomato plants provided significantly enhanced thermotolerance with better growth performance in Photosystem II (PSII) maximum photochemical quantum yield (Fv/Fm) and alleviated heat injury. Both exogenous melatonin treatment and endogenous melatonin manipulation by SlSNAT overexpression decreased the levels of reactive oxygen species�accumulation and Fv/Fm. The SlSNAT overexpression line showed protected ribulose bisphosphate carboxylase oxygenase proteins and upregulated response of heat transcription factors and heat shock proteins under heat stress. HSP40, a DnaJ-type chaperone, was found to interact with SlSNAT in the chloroplast. Downregulation of HSP40 showed lower melatonin synthesis under heat stress. HSP40 functions as a chaperone to protect the SNAT enzyme during melatonin synthesis under heat stress. HSP40 interacted with SlSNAT and together participated in melatonin-related thermotolerance regulation in tomato.

PDCD4 expression in coronary atherosclerosis rat models and its mechanism.

This study investigated the expression of programmed cell death protein 4 (PDCD4) in rat models of coronary atherosclerosis (AS) and analyzed its role and mechanism. A total of 80 Wistar rats were selected and divided into the control group (n=40) and research group (n=40) according to the principle of similar body weight, of which coronary AS models were established in rats in the research group. PDCD4 expression in coronary artery tissues was detected using western blotting, and the expression of interleukin-6 (IL-6) and IL-8 in the coronary artery tissues were measured by means of reverse transcription-polymerase chain reaction (RT-PCR). The apoptotic rate of coronary artery smooth muscle cells was determined via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The relative expression of PDCD4 in coronary artery tissues in the research group was obviously higher than that in the control group, and the difference was statistically significant (t=6.121, P<0.01). In terms of the relative expression of messenger ribonucleic acid (mRNA) of IL-6 in the coronary artery tissues, the research group had a remarkably higher level than the control group, with a statistically significant difference (t=21.03, P<0.01). The difference in the relative expression of IL-8 mRNA between the research group and the control group was statistically significant, of which a much higher level was detected in the research group (t=19.96, P<0.01). The apoptotic rate of smooth muscle cells in the research group was increased notably compared with that in the control group, and the difference was statistically significant (t=5.985, P<0.01). PDCD4 may participate in the formation of coronary AS plaque, and its possible function in the process is to inhibit the proliferation of vascular smooth muscle cells and promote the upregulation of IL-6 and IL-8.

Effects of glutamine on cytokines 1L-1 and TNF-α in rehabilitation and prognosis of patients with lobectomy.

This study was designed to investigate the effects of glutamine on cytokines 1L-1, TNF-α and prognosis of patients with lobectomy in the process of postoperative rehabilitation. A total of 78 patients with lung cancer who underwent lobectomy from January 2015 to January 2017 were selected in Daqing Oilfield General Hospital (Daqing, China). Patients were randomly divided into two groups, 39 patients in each group. Patients in the control group were treated with conventional treatment, while patients in the observation group were treated with both conventional and glutamine treatment. The levels of TNF-α, endotoxin, serum IL-1, IL-10, IL-15, IL-18 and intercellular adhesion molecule-1 (ICAM-1), myeloperoxidase (MPO) activity, incidence of nausea and vomiting, pulmonary histopathological changes, prognosis, and rehabilitation (time in bed, hospital stay and lung function) were compared between the two groups. Within 1 year after treatment, most patients survived, except 2 patients in the observation group and 3 patients in the control group who died. The rate of postoperation infection in the observation group was slightly lower than that in the control group. After treatment, the levels of endotoxin and TNF-α in the observation group were significantly lower than those in the control group (p<0.05). After treatment, the serum levels of IL-1 and IL-10 were significantly higher and the serum levels of IL-15 and IL-18 were significantly lower in the observation group than those in the control group (p<0.05). The expression levels of ICAM-1 and MPO activity were significantly higher in the observation group than those in the control group (p<0.05). No significant difference in the incidence of nausea and vomiting was found between the two groups (p>0.05). The average postoperative bed rest and hospital stay in the observation group were significantly shorter than those in the control group (p<0.05). The levels of forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) in the observation group were significantly higher than those in the control group (p<0.05). The results indicated that glutamine treatment is effective in the postoperative rehabilitation of patients undergoing lobectomy. Glutamine can regulate the levels of IL-1 and TNF-α, improve lung function, shorten bed rest and hospitalization days, promote patients postoperative rehabilitation process, and improve patients quality of life.

Baicalin attenuates high fat diet-induced insulin resistance and ectopic fat storage in skeletal muscle, through modulating the protein kinase B/Glycogen synthase kinase 3 beta pathway.

Insulin resistance is the pathophysiological basis of many diseases. Overcoming early insulin resistance highly significant in prevention diabetes, non-alcoholic fatty liver, and atherosclerosis. The present study aimed at evaluating the therapeutic effects of baicalin on insulin resistance and skeletal muscle ectopic fat storage in high fat diet-induced mice, and exploring the potential molecular mechanisms. Insulin resistance in mice was induced with a high fat diet for 16 weeks. Animals were then treated with three different doses of baicalin (100, 200, and 400 mg·kg(-1)·d(-1)) for 14 weeks. Fasting blood glucose, fasting serum insulin, glucose tolerance test (GTT), insulin tolerance test (ITT), and skeletal muscle lipid deposition were measured. Additionally, the AMP-activated protein kinase/acetyl-CoA carboxylase and protein kinase B/Glycogen synthase kinase 3 beta pathways in skeletal muscle were further evaluated. Baicalin significantly reduced the levels of fasting blood glucose and fasting serum insulin and attenuated high fat diet induced glucose tolerance and insulin tolerance. Moreover, insulin resistance was significantly reversed. Pathological analysis revealed baicalin dose-dependently decreased the degree of the ectopic fat storage in skeletal muscle. The properties of baicalin were mediated, at least in part, by inhibition of the AMPK/ACC pathway, a key regulator of de novo lipogenesis and activation of the Akt/GSK-3ß pathway, a key regulator of Glycogen synthesis. These data suggest that baicalin, at dose up to 400 mg·kg(-1)·d(-1), is safe and able to attenuate insulin resistance and skeletal muscle ectopic fat storage, through modulating the skeletal muscle AMPK/ACC pathway and Akt/GSK-3ß pathway.