Involvement of a rice mutation in storage protein biogenesis in endosperm and its genomic location.

MAIN CONCLUSION: A mutation was first found to cause the great generation of glutelin precursors (proglutelins) in rice (Oryza sativa L.) endosperm, and thus referred to as GPGG1. The GPGG1 was involved in synthesis and compartmentation of storage proteins. The PPR-like gene in GPGG1-mapped region was determined as its candidate gene. In the wild type rice, glutelins and prolamins are synthesized on respective subdomains of rough endoplasmic reticulum (ER) and intracellularly compartmentalized into different storage protein bodies. In this study, a storage protein mutant was obtained and characterized by the great generation of proglutelins combining with the lacking of 13 kD prolamins. A dominant genic-mutation, referred to as GPGG1, was clarified to result in the proteinous alteration. Novel saccular composite-ER was shown to act in the synthesis of proglutelins and 14 kD prolamins in the mutant. Additionally, a series of organelles including newly occurring several compartments were shown to function in the transfer, trans-plasmalemmal transport, delivery, deposition and degradation of storage proteins in the mutant. The GPGG1 gene was mapped to a 67.256 kb region of chromosome 12, the pentatricopeptide repeat (PPR)-like gene in this region was detected to contain mutational sites.

Identification of Novel Characteristics in TP53-Mutant Hepatocellular Carcinoma Using Bioinformatics.

Background: TP53 mutations are the most frequent mutations in hepatocellular carcinoma (HCC) and affect the occurrence and development of this cancer type. Therefore, it is essential to clarify the function and mechanism of TP53 mutations in HCC. Methods: We performed a sequence of bioinformatic analyses to elucidate the characteristics of TP53 mutations in HCC. We downloaded the data of hepatocellular carcinoma from The Cancer Genome Atlas database and used different R packages for serial analyses, including gene mutation analysis, copy number variation analysis, analysis of the tumor mutational burden and microsatellite instability, differential gene expression analysis, and functional enrichment analysis of TP53 mutations, and performed gene set enrichment analysis. We established a protein-protein interaction network using the STRING online database and used the Cytoscape software for network visualization, and hub gene screening. In addition, we performed anticancer drug sensitivity analysis using data from the Genomics of Drug Sensitivity in Cancer. Immune infiltration and prognosis analyses were also performed. Results: Missense mutations accounted for a great proportion of HCC mutations, the frequency of single nucleotide polymorphisms was high, and C > T was the most common form of single nucleotide variations. TP53 had a mutation rate of 30% and was the most commonly mutated gene in HCC. In the TP53 mutant group, the tumor mutational burden (p < 0.001), drug sensitivity (p < 0.05), ESTIMATE score (p = 0.038), and stromal score (p < 0.001) dramatically decreased. The Cytoscape software screened ten hub genes, including CT45A1, XAGE1B, CT55, GAGE2A, PASD1, MAGEA4, CTAG2, MAGEA10, MAGEC1, and SAGE1. The prognostic model showed a poor prognosis in the TP53 mutation group compared with that in the wild-type group (overall survival, p = 0.023). Univariate and multivariate cox regression analyses revealed that TP53 mutation was an independent risk factor for the prognosis of HCC patients (p <0.05). The constructed prognostic model had a favorable forecast value for the prognosis of HCC patients at 1 and 3 years (1-year AUC = 0.752, 3-years AUC = 0.702). Conclusion: This study further deepened our understanding of TP53-mutated HCC, provided new insights into a precise individualized therapy for HCC, and has particular significance for prognosis prediction.

Analysis of 27 antibiotic residues in raw cow's milk and milk-based products--validation of Delvotest® T.

Delvotest® T was evaluated for its capability at detecting residues of 27 antibiotics in raw cow's milk and in some dairy ingredients (skimmed and full-cream milk powders). The kit was used as a screening tool for the qualitative determination of antibiotics from different families in a single test. Results delivered by such a method are expressed as 'positive' or 'negative', referring to the claimed screening target concentration (STC). Validation was conducted according to the European Community Reference Laboratories' (CRLs) residues guidelines of 20 January 2010 and performed by two laboratories, one located in Europe and the other in Asia. Five criteria were evaluated including detection capability at STC, false-positive (FP) rate, false-negative (FN) rate, robustness and cross-reactivity using visual reading and Delvoscan®. STCs were set at or below the corresponding maximum residue limit (MRL), as fixed by European Regulation EC No. 37/2010. Four antibiotics (nafcillin, oxytetracycline, tetracycline and rifaximin) out of 27 had a false-negative rate ranging from 1.7% to 4.9%; however, it was still compliant with the CRLs' requirements. Globally, Delvotest T can be recommended for the analysis of the surveyed antibiotics in raw cow's milk, skimmed and full-cream milk powders. Additional compounds were tested such as sulfamethazine, spiramycin and erythromycin; however, detection at the corresponding MRL was not achievable and these compounds were removed from the validation. Other drugs from the sulfonamide, aminoglycoside or macrolide families not detected by the test at the MRL were not evaluated in this study. Regarding the reliability of this rapid test to milk-based preparations, additional experiments should be performed on a larger range of compounds and samples to validate the Delvotest T in such matrices.

[Determination of Flavonoids in Cycas revoluta Leaves by Chemiluminescence-Flow Injection Analysis Method].

OBJECTIVE: To detect flavonoids from Cycas revoluta leaves by means of Chemiluminescence-Flow Injection Analysis (CL-FIA). METHODS: Under alkaline condition, a CL-FIA method was established to determine flavonoids from leaves of Cycas revoluta on the basis of inhibiting effect of flavonoids to the Luminol-H2O2-Cu2+ chemiluminescence system and the reversed flow injection technique. RESULTS: In the range of 2. 0 x 10(-6) ~ 1. 0 x 10(-3) mg/mL, the decrease of CL intensity was correlated with flavonoids concentration while the detection limit was 0. 0265 µg/mL. Under the optimized conditions, the flavonoids of Cycas revoluta leaves were detected with its average rate reaching 1. 61% and RSD 1. 32%. CONCLUSION: Through the interference test and compared with the data of CL-FIA and UV, it is concluded that CL-FIA can be used in the analysis and detection of flavonoids from Cycas revoluta leaves.