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Leaf water potential of peanut subjected to drought stress is positively related to the oil content of peanut kernels. The aim of this study was to directly screen the high oil mutants of peanut and create the new peanut varieties using hydroxyproline as water potential regulator. In vitro mutagenesis was carried out with the embryonic leaflets of peanut variety Huayu 20 as explants and pingyangmycin as a mutagen added into the somatic embryo formation medium. The formed somatic embryos were successively transferred to somatic embryo germination and selection medium containing 6 mmol/L hydroxyproline (at -2.079 MPa water potential ) to induce regeneration and directionally screen high oil content mutants. After that, these plantlets were grafted and transplanted to the experimental field and 132 high oil mutants with oil content over 55% were obtained from the offspring of regenerated plants. Finally, among them, the oil contents of 27 lines were higher than 58% and of 2 lines were higher than 60%. A new peanut variety Yuhua 9 with high yield and oil content was bred from the regenerated plant progenies combining the pedigree breeding method. The yield was 14.0% higher than that of the control cultivar in the testing new peanut varieties of Liaoning province, and also it has passed the national registration of non-major crop varieties. Yuhua 9 with an oil content of 61.05%, which was 11.55 percentage points higher than that of the parent Huayu 20, was the peanut cultivar with the highest oil content in the world. The result showed that it was an effective way for directional breeding of high oil peanut varieties by means of the three-step technique including in vitro mutagenesis, directional screening by reducing water potential in medium and pedigree selection of regenerated plant progenies.

Oral cancer is a serious disease caused by environmental factors and/or susceptible genes. In the present study, in order to identify useful genetic biomarkers for cancer prediction and prevention, and for personalized treatment, we detected somatic mutations in 5 pairs of oral cancer tissues and blood samples using whole exome sequencing (WES). Finally, we confirmed a novel nonsense single-nucleotide polymorphism (SNP; chr19:15288426A>C) in the NOTCH3 gene with sanger sequencing, which resulted in a N1438T mutation in the protein sequence. Using multiple in silico analyses, this variant was found to mildly damaging effects on the NOTCH3 gene, which was supported by the results from analyses using PANTHER, SNAP and SNPs&GO. However, further analysis using Mutation Taster revealed that this SNP had a probability of 0.9997 to be 'disease causing'. In addition, we performed 3D structure simulation analysis and the results suggested that this variant had little effect on the solubility and hydrophobicity of the protein and thus on its function; however, it decreased the stability of the protein by increasing the total energy following minimization (-1,051.39 kcal/mol for the mutant and -1,229.84 kcal/mol for the native) and decreasing one stabilizing residue of the protein. Less stability of the N1438T mutant was also supported by analysis using I-Mutant with a DDG value of -1.67. Overall, the present study identified and confirmed a novel mutation in the NOTCH3 gene, which may decrease the stability of NOTCH3, and may thus prove to be helpful in cancer prognosis.

In this paper, we describe the structure of a N-terminal domain motif in nuclear-localized FKBP251-73, a member of the FKBP family, together with the structure of a sequence-related subdomain of the E3 ubiquitin ligase HectD1 that we show belongs to the same fold. This motif adopts a compact 5-helix bundle which we name the Basic Tilted Helix Bundle (BTHB) domain. A positively charged surface patch, structurally centered around the tilted helix H4, is present in both FKBP25 and HectD1 and is conserved in both proteins, suggesting a conserved functional role. We provide detailed comparative analysis of the structures of the two proteins and their sequence similarities, and analysis of the interaction of the proposed FKBP25 binding protein YY1. We suggest that the basic motif in BTHB is involved in the observed DNA binding of FKBP25, and that the function of this domain can be affected by regulatory YY1 binding and/or interactions with adjacent domains., (Copyright © 2014 Elsevier Inc. All rights reserved.)