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Water deficit is a key factor to induce flowering in many woody plants, but reports on the molecular mechanisms of floral induction and flowering by water deficit are scarce. Here, we analyzed the morphology, cytology, and different hormone levels of lemon buds during floral inductive water deficits. Higher levels of ABA were observed, and the initiation of floral bud differentiation was examined by paraffin sections analysis. A total of 1638 differentially expressed genes (DEGs) were identified by RNA sequencing. DEGs were related to flowering, hormone biosynthesis, or metabolism. The expression of some DEGs was associated with floral induction by real-time PCR analysis. However, some DEGs may not have anything to do with flowering induction/flower development; they may be involved in general stress/drought response. Four genes from the phosphatidylethanolamine-binding protein family were further investigated. Ectopic expression of these genes in Arabidopsis changed the flowering time of transgenic plants. Furthermore, the 5′ flanking region of these genes was also isolated and sequence analysis revealed the presence of several putative cis-regulatory elements, including basic elements and hormone regulation elements. The spatial and temporal expression patterns of these promoters were investigated under water deficit treatment. Based on these findings, we propose a model for citrus flowering under water deficit conditions, which will enable us to further understand the molecular mechanism of water deficit-regulated flowering in citrus. Highlight: Based on gene activity during floral inductive water deficits identified by RNA sequencing and genes associated with lemon floral transition, a model for citrus flowering under water deficit conditions is proposed.

The objective is to study whether the accumulation and utilization of plant N are controlled by Mo status in winter wheat cultivars. Mo-efficient cultivar 97003 (eff) and Mo-inefficient cultivar 97014 (ineff) were grown in severely Mo-deficient acidic soil (Tamm-reagent-extractable Mo 0.112 mg kg^(-1)) with (+Mo) and without (-Mo) the application of 0.13 mg kg^(-1) Mo. The accumulation and use efficiency of plant total N were significantly higher in +Mo than that in -Mo and in eff than that in ineff under Mo deficiency. N use efficiency was remarkably higher in maturity but it was forwarded to jointing stage after Mo supply, thus indicating that Mo supply promoted the N use efficiency besides N uptake and eff was efficient in N uptake and utilization. The overall activity of nitrate reductase (NR, EC 1.6.6.1) was significantly higher in +Mo than in -Mo and ratio of +Mo/-Mo was even to 14.8 at tillering stage for ineff. Activity of glutamine synthetase (GS, EC 6.3.1.2) was significantly lower in +Mo than in -Mo. Concentration of nitrate and glutamate were also significantly lower in +Mo than in -Mo, thus provided evidences for enhancing N use efficiency by Mo supply. Activities of NR and GS were significantly higher and concentrations of nitrate and glutamate were significantly lower in eff than ineff under Mo deficiency, thus indicated eff was more efficient in N reduction and utilization. It is therefore concluded that Mo could promote N accumulation and utilization in winter wheat which was directly related to NR and feedback regulated by GS. Higher Mo status also results in higher accumulation and utilization of plant N in eff.

Aims: Micro-ribonucleic acid (miRNA) are noncoding RNA molecules of 21 to 24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNA play essential roles in embryogenesis, cell differentiation and pathogenesis of human diseases. This study describes a comparison between the microRNA profile of human-papillomavirus-negative cervical squamous cell carcinoma patients and controls, in order to develop further understanding of the pathogenesis of cervical squamous cell carcinomas. Methods: MiRNA were isolated from tumor tissues of five human-papillomavirus-negative cervical squamous cell carcinoma patients and five healthy controls in order to perform miRNA microarray chip analysis. The chip results were then confirmed by northern blot analysis. Results: A total of 27 miRNA differentially expressed between the squamous cell carcinoma patients and the healthy controls were identified. Conclusion: This work indicates that these miRNA may be potential diagnosis biomarkers and probable factors involved in the pathogenesis of cervical squamous cell carcinomas.

A hydroponic experiment was conducted to investigate the effects of arsenic (As) stress on growth, nutrition and As uptake, and speciation in shoots and roots of winter wheat ( Triticum aestivum L.). Winter wheat has high tolerance to As. Most As is accumulated in the roots, and an As concentration of 4,421 mg/kg was observed at a solution concentration of 20 mg/L As. Arsenic concentrations in roots were approximately 40–100 times greater than those in shoots. Arsenic in winter wheat roots and shoots occurred as both As 3 + and As 5 + species, although As 3 + was the main species in winter wheat tissues. Arsenic significantly decreased the biomass of winter wheat shoots and roots and affected absorption and transport of micro- and macro-elements in winter wheat tissue. Arsenic treatment significantly increased the concentrations of total Magnesium (Mg) and calcium (Ca) in shoots and enhanced the transport of Mg and Ca from roots to shoots but decreased potassium (K), nitrogen (N), and phosphorus (P) concentrations in both shoots and roots, particularly the concentration of P. Concentrations of iron, copper, and zinc in winter wheat shoots were negatively related to As rates, with correlation coefficients ( R 2 ) of 0.93, 0.94, and 0.97, respectively.

Background and Aim: MicroRNAs (miRNAs) are non-coding RNA molecules of 21–24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNAs play essential roles in embryogenesis, cell differentiation, and pathogenesis of human diseases including cancer. Methods: We analyzed the miRNA expression profiles in 10 pairs of hepatocellular carcinoma (HCC) and adjacent non-tumorous tissue (NT) from 10 non-viral hepatitis patients, using a mammalian miRNA microarray containing whole human mature and precursor miRNA sequences. Results: A total of 15 miRNAs exhibited higher expression in the HCC samples than that in the NT samples, and one miRNA demonstrated lower expression in the HCC samples than in the NT samples. A total of 18 miRNAs identified valid expression only in HCC samples, with six only in NT samples. The chip results were confirmed by Northern blot analysis. Conclusion: Our study may help clarify the molecular mechanisms involved in the pathogenesis of HCC, and miRNAs potentially serve as a novel diagnostic tool of HCC.