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Hui, W.

Publications and source records attributed to Hui, W..

3 recordsLinked to original sources

Isolation and characterization of a neoxanthin synthase gene functioning in fucoxanthin biosynthesis of Phaeodactyum tricornutum

Golden-brown xanthophyll fucoxanthin in marine organisms, especially in diatoms, has attracted widespread attention because of its diverse biological activities. However, the biosynthetic pathway of fucoxanthin remains unclear in diatoms. Fucoxanthin may derive from either neoxanthin or diadinoxanthin pathway. However, the key point is whether neoxanthin and its synthesizing genes exist or not. In this study, we successfully identified a few xanthophylls in trace amounts in the concentrated fraction of carotenoids of diatom Phaeodactylum tricornutum cultured at different light intensities with the co-chromatography method, and cloned the neoxanthin synthase (NXS) gene which was not annotated in diatom genome. The NXS knockdown and knockout experiment show a positive correlation in the accumulation of neoxanthin and zeaxanthin while a negative correlation in violaxanthin and fucoxanthin with the expression of NXS. In vitro assay evidenced that neoxanthin is the precursor for fucoxanthin biosynthesis, indicating that other molecules intermediate the conversion between violaxanthin and fucoxanthin. Overall, we cloned a novel gene functioning in neoxanthin biosynthesis, which should aid to clarifying the fucoxanthin biosynthetic pathway in diatom.

molecular biology↗

DNA binding domain undergoes dynamic and selective protein-protein interactions to facilitate CTCF insulation

CTCF is required for three-dimensional chromatin organization and a predominant insulator protein. However, its roles in insulating enhancers have not been fully explained in 3D nuclear organization. Here, we found that the CTCF DNA binding domain (DBD) forms dynamic self-interacting clusters. We next investigated the spatial relationships between these clusters and other transcription regulators with a light-induced imaging system. Strikingly, CTCF DBD clusters were found to incorporate other insulator proteins but are not coenriched with transcriptional activators in the nucleus. This property is not observed in other domains of CTCF or the DBDs of other transcription factors. Moreover, endogenous CTCF shows a phenotype consistent with the DBD by forming small protein clusters and interacts less transcriptional activators bound, CTCF motif arrays. Our results reveal an interesting phenomenon that CTCF DBD interacts with insulator proteins and selectively localizes to nuclear positions with lower concentrations of transcriptional activators, providing new insights into the insulation function of CTCF.

molecular biology↗

A learning-based framework for miRNA-disease association prediction using neural networks

MotivationA microRNA (miRNA) is a type of non-coding RNA, which plays important roles in many bio-logical processes. Lots of studies have shown that miRNAs were implicated in human diseases, indicating that miRNAs might be potential biomarkers for various types of diseases. Therefore, it is important to reveal the relationships between miRNAs and diseases/phenotypes.\n\nResultsWe proposed a novel learning-based framework, MDA-CNN, for miRNA-disease association identification. The model first captures richer interaction features between diseases and miRNAs based on a three-layer network with an additional gene layer. An auto-encoder is then employed to identify the essential feature combination for each pair of miRNA and disease automatically. A final label is given by a convolutional neural network taking the reduced feature representation as input. The evaluation results showed that the proposed framework outperformed some state-of-the-art approaches in a large margin on both tasks of miRNA-disease associations prediction and miRNA-phenotype associations prediction.\n\nAvailabilityThe software will be available after the manuscript is accepted.\n\nContactjiajiepeng@nwpu.edu.cn;zywei@fudan.edu.cn;shang@nwpu.edu.cn\n\nSupplementary informationSupplementary data are available at Bioinformatics online.

bioinformatics↗