Morpho-anatomical and physiological responses to waterlogging stress in different barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) genotypes

Waterlogging is one of the major stresses limiting crop production worldwide. The understanding of the mechanisms of plant adaptations to waterlogging stress helps improve plant tolerance to stress. In this study, physiological responses and morpho-anatomical adaptations of seven different barley genotypes were investigated under waterlogging stress. The results showed that the waterlogging-tolerant varieties (TX9425, Yerong, TF58) showed less reduction in plant height, SPAD (soil–plant analyses development analyses) value, tillers, shoot and root biomasses than did the waterlogging-sensitive varieties (Franklin, Naso Nijo, TF57). Under waterlogging stress condition, the tolerant genotypes also showed a much larger number of adventitious roots than did the sensitive genotypes. More intercellular spaces and better integrated chloroplast membrane structures were observed in the leaves of the waterlogging-tolerant cultivars, which is likely due to increased ethylene content, decreased ABA content and less accumulation of O₂^.?. The ability to form new adventitious roots and intercellular spaces in shoots can also be used as selection criteria in breeding barley for waterlogging tolerance.     

Negative regulation of AMPK signaling by high glucose via E3 ubiquitin ligase MG53

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Exploration research on the fusion of multimodal spectrum technology to improve performance of rapid diagnosis scheme for thyroid dysfunction

The spectral fusion by Raman spectroscopy and Fourier infrared spectroscopy combined with pattern recognition algorithms is utilized to diagnose thyroid dysfunction serum, and finds the spectral segment with the highest sensitivity to further advance diagnosis speed. Compared with the single infrared spectroscopy or Raman spectroscopy, the proposal can improve the detection accuracy, and can obtain more spectral features, indicating greater differences between thyroid dysfunction and normal serum samples. For discriminating different samples, principal component analysis (PCA) was first used for feature extraction to reduce the dimension of high‐dimension spectral data and spectral fusion. Then, support vector machine (SVM), back propagation neural network, extreme learning machine and learning vector quantization algorithms were employed to establish the discriminant diagnostic models. The accuracy of spectral fusion of the best analytical model PCA‐SVM, single Raman spectral accuracy and single infrared spectral accuracy is 83.48%, 78.26% and 80%, respectively. The accuracy of spectral fusion is higher than the accuracy of single spectrum in five classifiers. And the diagnostic accuracy of spectral fusion in the range of 2000 to 2500 cm^?1 is 81.74%, which greatly improves the sample measure speed and data analysis speed than analysis of full spectra. The results from our study demonstrate that the serum spectral fusion technique combined with multivariate statistical methods have great potential for the screening of thyroid dysfunction.     

Ten-a Affects the Fusion of Central Complex Primordia in Drosophila

The central complex of Drosophila melanogaster plays important functions in various behaviors, such as visual and olfactory memory, visual orientation, sleep, and movement control. However little is known about the genes regulating the development of the central complex. Here we report that a mutant gene affecting central complex morphology, cbd (central brain defect), was mapped to ten-a, a type II trans-membrane protein coding gene. Down-regulation of ten-a in pan-neural cells contributed to abnormal morphology of central complex. Over-expression of ten-a by C767-Gal4 was able to partially restore the abnormal central complex morphology in the cbd mutant. Tracking the development of FB primordia revealed that C767-Gal4 labeled interhemispheric junction that separated fan-shaped body precursors at larval stage withdrew to allow the fusion of the precursors. While the C767-Gal4 labeled structure did not withdraw properly and detached from FB primordia, the two fan-shaped body precursors failed to fuse in the cbd mutant. We propose that the withdrawal of C767-Gal4 labeled structure is related to the formation of the fan-shaped body. Our result revealed the function of ten-a in central brain development, and possible cellular mechanism underlying Drosophila fan-shaped body formation.     

A doubly auxotrophic CHO-K1 cell line for the production of recombinant monoclonal antibodies

Chinese hamster ovary (CHO) cells are the most widely used mammalian hosts for recombinant protein production due to their hardiness, ease of transfection, and production of glycan structures similar to those in natural human monoclonal antibodies. To enhance the usefulness of CHO-K1 cells we developed a new selection system based on double auxotrophy. We used CRISPR-Cas9 to knockout the genes that encode the bifunctional enzymes catalyzing the last two steps in the de novo synthesis of pyrimidines and purines (uridine monophosphate synthase and 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase [ATIC], respectively). Survival of these doubly auxotrophic cells depends on the provision of sources of purines and pyrimidines or on the transfection and integration of open reading frames encoding these two enzymes. We successfully used one such double auxotroph (UA10) to select for stable transfectants carrying (a) the recombinant tumor necrosis factor-α receptor fusion protein etanercept and (b) the heavy and light chains of the anti-Her2 monoclonal antibody trastuzumab. Transfectant clones produced these recombinant proteins in a stable manner and in substantial amounts. The availability of this double auxotroph provides a rapid and efficient selection method for the serial or simultaneous transfer of genes for multiple polypeptides of choice into CHO cells using readily available purine- and pyrimidine-free commercial media.