Editing of a Novel Cd Uptake-Related Gene CUP1 Contributes to Reducing Cd Accumulations in Arabidopsis thaliana and Brassica napus.

Brassica napus is a Cd hyperaccumulator, which is a serious threat to food and fodder safety. However, no related studies on developing Cd-safe B. napus have been reported yet. Here, we screened out a novel Cd uptake-related gene, AtCUP1, from the major facilitator superfamily in Arabidopsis thaliana. The mutation of AtCUP1 decreased Cd accumulation, both in roots and shoots of A. thaliana. Furthermore, the disruption of the AtCUP1 gene by the CRISPR/Cas9 system significantly reduced Cd accumulation in A. thaliana. Interestingly, the disruption of the BnCUP1 gene, an orthologous gene of AtCUP1, by the CRISPR/Cas9 system also diminished Cd accumulation in both roots and shoots of B. napus based on the hydroponics assay. Furthermore, for the field experiment, the Cd accumulations of BnCUP1-edited lines were reduced by 52% in roots and 77% in shoots compared to that of wild-type (WT) lines, and the biomass and yield of BnCUP1-edited lines increased by 42% and 47% of that of WT, respectively. Noteworthily, agronomic characteristics of B. napus were not apparently affected by BnCUP1-editing. Thus, BnCUP1-edited lines are excellent non-transgenic germplasm resources for reducing Cd accumulation without a distinct compromise in yield, which could be applied to agricultural production in Cd-contaminated soils.

The rs35874116 single nucleotide polymorphism increases sweet intake and the risk of severe early childhood caries: a case-control study.

BACKGROUND: Dental caries is one of the most prevalent chronic diseases worldwide among children. The rs35874116 single nucleotide polymorphism (SNP) in the sweet receptor gene TAS1R2 has been associated with dental caries at a high risk in permanent teeth among school children and adults. To date, little is known about the association of this SNP with sweet intake and caries risk in the primary school children. METHODS: Total of 236 children were included, namely 118 subjects in the non-caries (NC) group and severe early childhood caries (S-ECC) group, respectively. Oral mucosa cells were collected from all the selected children, and the full length of exon 3 in TAS1R2 was sequenced to analyse rs35874116 polymorphism. A questionnaire was used to collect information about socio-demographic information, frequency of sweet intake and oral hygiene habits. Multiple logistic regression models were applied to assess the relationship of rs35874116 polymorphism with frequency of sweet intake and S-ECC among the five-year-old children. RESULTS: Children with the TT genotype of rs35874116 had a higher frequency of sweet intake than CT/CC carriers (51.3% vs. 32.7%; x2 = 5.436, p = 0.020), and S-ECC individuals were more likely to be TT genotype carriers than NC individuals (53.5% vs. 46.5%; x2 = 4.353, p = 0.037). Multiple logistic regression analyses showed that the TT genotype of rs35874116 was not only significantly related to the frequency of sweet intake (OR = 2.25, 95% CI = 1.14-4.44) but also significantly associated with S-ECC (OR = 2.11, 95% CI = 1.01 ~ 4.42). CONCLUSIONS: The rs35874116 polymorphism might increase sweet intake and the risk of S-ECC among five-year-old children in Nanning, China.

A protein-independent fluorescent RNA aptamer reporter system for plant genetic engineering.

Reporter systems are routinely used in plant genetic engineering and functional genomics research. Most such plant reporter systems cause accumulation of foreign proteins. Here, we demonstrate a protein-independent reporter system, 3WJ-4 × Bro, based on a fluorescent RNA aptamer. Via transient expression assays in both Escherichia coli and Nicotiana benthamiana, we show that 3WJ-4 × Bro is suitable for transgene identification and as an mRNA reporter for expression pattern analysis. Following stable transformation in Arabidopsis thaliana, 3WJ-4 × Bro co-segregates and co-expresses with target transcripts and is stably inherited through multiple generations. Further, 3WJ-4 × Bro can be used to visualize virus-mediated RNA delivery in plants. This study demonstrates a protein-independent reporter system that can be used for transgene identification and in vivo dynamic analysis of mRNA.

Tumor Microenvironment-Activated and Viral-Mimicking Nanodrugs Driven by Molecular Precise Recognition for dNTP Inhibition-Induced Synergistic Cancer Therapy.

The medical application of nanotechnology is promising for cancer chemotherapy. However, most of the small-molecule drug assemblies still have such disadvantages as serious drug leakage and nonideal synergistic mechanisms, resulting in undesired therapeutic effect. Both nucleoside analogue-based clofarabine (CA) and methotrexate (MTX) were used as the first-line anticancer medication. However, a single-agent chemotherapy still faced many challenges including low bioavailability and toxic side effects to normal tissues due to nonspecific biodistribution of drugs. Herein, we designed and fabricated novel viral-mimicking and carry-free nanodrugs (CA-MTX NPs) via molecular recognition-driven precise self-assembly between CA and MTX. After introduction of mild acid-responsive PEG-lipid on the surface of CA-MTX NPs, the synthetic nanodrugs with a diameter of ∼150 nm exhibited tumor microenvironment-activated characteristics and self-targeting property. The results suggested that our nanodrugs could achieve superior tumor accumulation and synergistically promote the tumor suppression by collaboratively inhibiting dNTP pools. We foresaw that the well-designed smart nanodrugs delivery system would open a new avenue in synergistic cancer therapeutics.

Impact of parental migration on oral health outcomes of left-behind school-aged children in Luchuan, southern China.

BACKGROUND: With rapid urbanization in China, an increasing number of rural adults have migrated to cities to seek job opportunities, leaving their school-aged children behind. These left-behind children (LBC) without one or both parents usually receive less attention from their caregivers. Whether the parental migration affects the children's oral health is not well understood. This study aimed to explore the differences in dental caries status and oral health-related behaviors between children with different parental migration experiences in a rural area of Southern China. METHODS: A cross-sectional study was conducted in Luchuan County of Guangxi Province in 2015. A total of 1085 school children aged 8-12 participated in this study. Participants' demographic characteristics, parental migration information, and eating and oral hygiene habits were collected using a self-administered questionnaire. Dental caries of permanent teeth was examined using the decayed, missing, and filled tooth (DMFT) index recommended by the World Health Organization. Dental caries experience and oral health-related behaviors were compared between LBC and non-LBC, as well as children with different experiences of parental migrations. The impact of various parental migration attributes on LBC oral health outcomes was examined by univariate and multivariate analyses. RESULTS: Among the school-aged children examined, 60.9% of them were LBC. Only 29.7% of the children brushed their teeth regularly; 86.5% of them did not know what fluoride toothpaste was. Caries prevalence was 51.4% for LBC and 40.8% for non-LBC (p < 0.001). The LBC experienced a greater DMFT mean (1.20 ± 1.59) compared to the non-LBC (0.85 ± 1.30) (p < 0.001). Oral health-related behaviors were not significantly different between LBC and non-LBC. Dental caries experience and oral health-related behaviors were not related to the type or duration of parental migration. Multiple regression analyses showed that parental migration was one of significant predictors of children's caries outcome; LBC had a higher risk to caries than non-LBC (95% CI =1.26, 2.09). CONCLUSIONS: These findings indicate that parental migration could be a significant risk factor for caries development among 8- to 12-year-old school children in rural China.