miR164g-MsNAC022 acts as a novel module mediating drought response by transcriptional regulation of reactive oxygen species scavenging systems in apple.

Under drought stress, reactive oxygen species (ROS) overaccumulate as a secondary stress that impairs plant performance and thus severely reduces crop yields. The mitigation of ROS levels under drought stress is therefore crucial for drought tolerance. MicroRNAs (miRNAs) are critical regulators of plant development and stress responses. However, the complex molecular regulatory mechanism by which they function during drought stress, especially in drought-triggered ROS scavenging, is not fully understood. Here, we report a newly identified drought-responsive miRNA, miR164g, in the wild apple species Malus sieversii and elucidate its role in apple drought tolerance. Our results showed that expression of miR164g is significantly inhibited under drought stress and it can specifically cleave transcripts of the transcription factor MsNAC022 in M. sieversii. The heterologous accumulation of miR164g in Arabidopsis thaliana results in enhanced sensitivity to drought stress, while overexpression of MsNAC022 in Arabidopsis and the cultivated apple line 'GL-3' (Malus domestica Borkh.) lead to enhanced tolerance to drought stress by raising the ROS scavenging enzymes activity and related genes expression levels, particularly PEROXIDASE (MsPOD). Furthermore, we showed that expression of MsPOD is activated by MsNAC022 in transient assays. Interestingly, Part1 (P1) region is the key region for the positive regulation of MsPOD promoter by MsNAC022, and the different POD expression patterns in M. sieversii and M. domestica is attributed to the specific fragments inserted in P1 region of M. sieversii. Our findings reveal the function of the miR164g-MsNAC022 module in mediating the drought response of M. sieversii and lay a foundation for breeding drought-tolerant apple cultivars.

[Analysis of peptides and proteins from Asini Corii Colla using nano LC-Q-Exactive-MS/MS].

This paper aims to systematically analyze the peptides and proteins from Asini Corii Colla(ACC) through shotgun proteomics. After high-pH reversed-phase fractionation, the proteins and peptides in the hydrolysate of ACC were further separated by nano LC-Q-Exactive-MS/MS under the following conditions: Thermo Scientific EASY column(100 µm×2 cm, 5 µm, C_(18)) as precolumn, Thermo Scientific EASY column(75 µm×100 mm, 3 µm, C_(18)) for solid phase extraction, gradient elution with 0.1% formic acid in water(mobile phase A) and 84% acetonitrile in water containing 0.1% formic acid(mobile phase B), and MS in positive ion mode. Based on Uniprot_Equus caballus, MS data, and literature, 2 291 peptides were identified from ACC by MaxQuant, with 255 Maillard reactions(AML, CML, CEL)-modified peptides identified for the first time. Through alignment, the peptides were found to belong to 678 equine proteins. In conclusion, the combination of nano LC-Q-Exactive-MS/MS and shotgun proteomics achieved rapid and accurate identification of the proteins and peptides in ACC, which provides the key information and new insights for further investigation of chemicals and effective substances in ACC.

A Nematode Calreticulin, Rs-CRT, Is a Key Effector in Reproduction and Pathogenicity of Radopholus similis.

Radopholus similis is a migratory plant-parasitic nematode that causes severe damage to many agricultural and horticultural crops. Calreticulin (CRT) is a Ca2+-binding multifunctional protein that plays key roles in the parasitism, immune evasion, reproduction and pathogenesis of many animal parasites and plant nematodes. Therefore, CRT is a promising target for controlling R. similis. In this study, we obtained the full-length sequence of the CRT gene from R. similis (Rs-crt), which is 1,527-bp long and includes a 1,206-bp ORF that encodes 401 amino acids. Rs-CRT and Mi-CRT from Meloidogyne incognita showed the highest similarity and were grouped on the same branch of the phylogenetic tree. Rs-crt is a multi-copy gene that is expressed in the oesophageal glands and gonads of females, the gonads of males, the intestines of juveniles and the eggs of R. similis. The highest Rs-crt expression was detected in females, followed by juveniles, eggs and males. The reproductive capability and pathogenicity of R. similis were significantly reduced after treatment with Rs-crt dsRNA for 36 h. Using plant-mediated RNAi, we confirmed that Rs-crt expression was significantly inhibited in the nematodes, and resistance to R. similis was significantly improved in transgenic tomato plants. Plant-mediated RNAi-induced silencing of Rs-crt could be effectively transmitted to the F2 generation of R. similis; however, the silencing effect of Rs-crt induced by in vitro RNAi was no longer detectable in F1 and F2 nematodes. Thus, Rs-crt is essential for the reproduction and pathogenicity of R. similis.

Low-dose metronomic chemotherapy with cisplatin: can it suppress angiogenesis in H22 hepatocarcinoma cells?

Low-dose chemotherapy drugs can suppress tumours by restraining tumour vessel growth and preventing the repair of damaged vascular endothelial cells. Cisplatin is a broad-spectrum, cell cycle-non-specific drug, but has serious side effects if used at high doses. There have been few reports on the anti-angiogenic effects of low-dose cisplatin and hence the effect of low-dose metronomic (LDM) chemotherapy on the proliferation and neovascularization of H22 hepatocarcinoma cells is discussed in this research. The influence of LDM chemotherapy with cisplatin on human umbilical vascular endothelial cells (HUVECs) and proliferation of the HepG(2) human hepatocarcinoma cell line were measured using MTT assays. The LDM group was treated with cisplatin 0.6 mg/kg/day; the control group with saline 0.2 ml; the maximum tolerated dose (MTD) group with cisplatin 9 mg/kg/day. Vascular endothelial growth factor (VEGF) and matrix metallopeptidase 2 (MMP-2) were detected using immunohistochemical staining. A chicken chorio-allantoic membrane (CAM) model was used to check the inhibitory effect of LDM chemotherapy with cisplatin on neovascularization in vivo. Low-dose cisplatin inhibited HUVEC proliferation in a dose- and time-dependent manner, but was ineffective in inhibiting HepG(2) cell proliferation. Tumour growth was delayed in mice receiving LDM cisplatin, without apparent body weight loss, compared with mice that received MTD cisplatin. Microvessel density and expression of VEGF and MMP-2 were much lower in mice receiving LDM cisplatin than in the control and MTD groups. Continuous low-dose cisplatin suppressed CAM angiogenesis in vivo. LDM chemotherapy with cisplatin can inhibit the growth of blood vessel endothelial cells in vitro and shows anti-angiogenic ability in vivo.

[Content comparison of polyamines compounds in Penis et Testis Cervi].

OBJECTIVE: To compare the content of the main polyamines compositions in 10 samples of Penis et Testis Cervi from different species and habitats. MEHTODs: The putrescine spermidine and spermine in Penis et Testis Cervi were determined by HPLC. RESULTS: The contents of total Polyamine and 3 kinds of polyamines compositions in all samples were different. CONCLUSION: The content of the main polyamines compositions can be used to control the quality of Penis et Testis Cervi.