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Puccinia graminis f. sp. tritici (Pgt), the causal agent of wheat stem rust, poses a significant threat to global wheat production. Genetic resistance offers a cost-effective and sustainable solution. The durum wheat landrace PI 94701 was previously hypothesized to carry two stem rust resistance (Sr) genes, but their chromosomal locations were unknown. In this study, we mapped and characterized an all-stage Sr gene in PI 94701, temporarily designated as SrPI94701. In seedling tests, SrPI94701 was effective against all six Pgt races tested. Using a large segregating population, we mapped SrPI94701 on chromosome arm 5BL within a 0.17-cM region flanked by markers pku69124 and pku69228, corresponding to 1.04 and 2.15 Mb genomic regions in the Svevo and Chinese Spring reference genomes. Within the candidate region, eight genes exhibited differential expression between the Pgt-inoculated resistant and susceptible plants. Among them, two nucleotide-binding leucine-rich repeat (NLR) genes, TraesCS5B03G1334700 and TraesCS5B03G1335100, showed high polymorphism between the parental lines and were upregulated in Pgt-inoculated resistant plants. However, the flanking and completely linked markers developed in this study could not accurately predict the presence of SrPI94701 in a survey of 104 wheat accessions. SrPI94701 is a promising resource for enhancing stem rust resistance in wheat breeding programs. [ABSTRACT FROM AUTHOR]

Key message: The rust resistance genes Lr53 and Yr35 were introgressed into bread wheat from Aegilops longissima or Aegilops sharonensis or their S-genome containing species and mapped to the telomeric region of chromosome arm 6BS. Wheat leaf and stripe rusts are damaging fungal diseases of wheat worldwide. Breeding for resistance is a sustainable approach to control these two foliar diseases. In this study, we used SNP analysis, sequence comparisons, and cytogenetic assays to determine that the chromosomal segment carrying Lr53 and Yr35 was originated from Ae.longissima or Ae. sharonensis or their derived species. In seedling tests, Lr53 conferred strong resistance against all five Chinese Pt races tested, and Yr35 showed effectiveness against Pst race CYR34 but susceptibility to race CYR32. Using a large population (3892 recombinant gametes) derived from plants homozygous for the ph1b mutation obtained from the cross 98M71 × CSph1b, both Lr53 and Yr35 were successfully mapped to a 6.03-Mb telomeric region of chromosome arm 6BS in the Chinese Spring reference genome v1.1. Co-segregation between Lr53 and Yr35 was observed within this large mapping population. Within the candidate region, several nucleotide-binding leucine-rich repeat genes and protein kinases were identified as candidate genes. Marker pku6B3127 was completely linked to both genes and accurately predicted the absence or presence of alien segment harboring Lr53 and Yr35 in 87 tetraploid and 149 hexaploid wheat genotypes tested. We developed a line with a smaller alien segment (< 6.03 Mb) to reduce any potential linkage drag and demonstrated that it conferred resistance levels similar to those of the original donor parent 98M71. The newly developed introgression line and closely linked PCR markers will accelerate the deployment of Lr53 and Yr35 in wheat breeding programs. [ABSTRACT FROM AUTHOR]

Path planning is the core technology of mobile robot decision-making and control and is also a research hotspot in the field of artificial intelligence. Aiming at the problems of slow response speed, long planning path, unsafe factors, and a large number of turns in the conventional path planning algorithm, an improved multiobjective genetic algorithm (IMGA) is proposed to solve static global path planning in this paper. The algorithm uses a heuristic median insertion method to establish the initial population, which improves the feasibility of the initial path and generates a multiobjective fitness function based on three indicators: path length, path security, and path energy consumption, to ensure the quality of the planned path. Then, the selection, crossover, and mutation operators are designed by using the layered method, the single-point crossover method, and the eight-neighborhood-domain single-point mutation method, respectively. Finally, the delete operation is added, to further ensure the efficient operation of the mobile robot. Simulation experiments in the grid environment show that the algorithm can improve the defects of the traditional genetic algorithm (GA), such as slow convergence speed and easy to fall into local optimum. Compared with GA, the optimal path length obtained by planning is shortened by 17%. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is caused by pathogenic variants or mutations in the NF1 gene that encodes neurofibromin.We describe here a new approach to determining the functional consequences of NF1 genetic variants.We established a heterologous cell culture expression system using a full-length mouse Nf1 cDNA (mNf1) and human cell lines. We demonstrate that the fulllength murine cDNA produces a > 250 kDa neurofibromin protein that is capable of modulating Ras signaling.We created mutant cDNAs representing NF1 patient variants with different clinically relevant phenotypes, and assessed their ability to produce mature neurofibromin and restore Nf1 activity in NF1-/- cells. These cDNAs represent variants in multiple protein domains and various types of clinically relevant predicted variants. This approach will help advance research on neurofibromin structure and function, determine pathogenicity for missense variants, and allow for the development of activity assays and variant-directed therapeutics. [ABSTRACT FROM AUTHOR]

The petroleum production has been raised sharply over the past decades, whereas the petroleum exploitation has also caused serious environmental contamination. A pot experiment has been conducted to monitor the dynamic response of antioxidant defense system and the growth reaction of Amorpha fruticosa seedlings to soil petroleum contamination. The results show that (1) in 5 g kg contaminated soil, A. fruticosa removes reactive oxygen species (ROS) by increasing the activities of antioxidant enzymes (glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT)), while in 10-15 g kg long-term contaminated soil, A. fruticosa removes ROS by the cooperation of antioxidant enzymes and antioxidants (SOD, CAT, ascorbate peroxidase (APX), GR, ascorbic acid (AsA), glutathione (GSH), and proline (Pro)). In long-term 20 g kg contaminated soil, the defense ability of APX and AsA decreases sharply, and A. fruticosa removes the ROS by the synergistic effect of antioxidant enzymes (SOD and CAT) and antioxidants (GSH and Pro). Only in 20 g kg long-term petroleum contamination caused significant ( P < 0.05) increase in HO content in seedlings. (2) SOD, CAT, GR, GSH, and Pro exhibit increases in long-term severely contaminated soil, and these enzymes and antioxidants are the most important defender of A. fruticosa to ROS accumulation caused by petroleum contamination. (3) The growth of A. fruticosa seedlings is less affected in 5 g kg petroleum-contaminated soil, while it significantly decreases in 10, 15, and 20 g kg petroleum-contaminated soils ( P < 0.05). (4) Considering comprehensively the response of antioxidant defense system and the growth reaction of seedlings to petroleum contamination, A. fruticosa could be utilized for phytoremediation in ≤15 g kg contaminated soil. [ABSTRACT FROM AUTHOR]

Soluble growth factors play an important role in the coordination and integration of cell proliferation, differentiation, fate determination, and morphogenesis during development of multicellular organisms. Fibroblast growth factors (FGFs) are a large family of polypeptide growth factors that are present in organisms ranging from nematodes to humans. RNA alternative splicing of FGFs and their receptors further enhances the complexity of this ligand-receptor system. The mouse Fgf8 gene produces eight splice variants, which encode isoform proteins with different N-termini and distinct receptor-binding affinity and biological activity. In this article, we review the roles of Fgf8 in vertebrate development and summarize the recent findings on the in vivo function of different Fgf8 splice variants. We propose that multiple Fgf8 isoform proteins act in concert to regulate the overall function of Fgf8 and account for the diverse and essential role of Fgf8 during vertebrate development. J. Cell. Physiol. 226: 1722-1726, 2011. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Being supportive cells for neurons in the central nervous system, astrocytes have recently found to be associated with neurogenesis. Ventral mesencephalon (VM) astrocytes were also detected being instructive for VM dopaminergic (DA) neurogenesis, but the underling mechanisms are still unclear. This research is to figure out whether VM astrocytes are more efficient than those from other brain regions in inducing VM DA neurons from their precursors and whether transforming growth factor-βs (TGF-βs) are the underlying molecules. We found that, compared with astrocytes preparations from striatum and hippocampus, VM astrocytes preparations displayed markedly higher efficacy in inducing DA neurogenesis. Besides, they also expressed higher level of TGF-β3 than those of two other regions. When TGF-β3 gene expression in astrocytes preparations was inhibited by its antisense oligonucleotide, the induction of DA neurons decreased to a similar level among these three astrocytes preparations. Thus, our experiment indicates that VM astrocytes preparations which contained highly purified astrocytes are more efficient in inducing DA neurogenesis than those from other regions. Furthermore, it also suggests that the regional differences are regulated by different expression levels of TGF-β3 in those astrocytes preparations from different derivations. [ABSTRACT FROM AUTHOR]

By using H2PtCl6 and titanate nanotubes as precursor, platinum-loaded TiO2 nanotubes (Pt/TiO2NTs) are prepared at different pH by deposition-precipitation method. The prepared materials are characterized with powder x-ray diffraction (XRD) and x-ray photoelectron spectra (XPS). Their photocatalytic performance is evaluated by the degradation rates of methyl orange solution under UV-vis light irradiation. Obtained results indicate that the pH of H2PtCl6 solution has obvious influence on the catalytic performance of Pt/TiO2NTs. [ABSTRACT FROM AUTHOR]