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Lin, Y.-J.

Publications and source records attributed to Lin, Y.-J..

3 recordsLinked to original sources

HBx enhances CPAP expression via interacting with CREB to promote hepatocarcinogenesis in HBV-associated HCC

Hepatitis B virus (HBV) encoded non-structure protein X (HBx) can promote cell proliferation, migration, and anti-apoptosis via activating several transcription factors and increasing their downstream gene expression in HBV-infected liver cells. Our previous report suggested that centrosomal P4.1-associated protein (CPAP) is required for HBx-mediated NF-{kappa}B activation. Here, we found that, upon HBV infection, overexpressed HBx can transcriptionally up-regulate CPAP via interacting with CREB. CPAP can directly interact with HBx to promote HBx-mediated cell proliferation and migration; and SUMO modification of CPAP is involved in interacting with HBx. Interestingly, CPAP can increase the HBx protein stability in an NF-{kappa}B-dependent manner; and overexpressed CPAP and HBx is positively correlated with the activation status of NF-{kappa}B in HCC. Increased expression of CREB and CPAP mRNAs exists in the high-risk group with a lower survival rate in hepatocellular carcinoma (HCC). These results suggest that the reciprocal regulation between CPAP and HBx may provide a microenvironment to facilitate HCC development via enhancing NF-{kappa}B activation, inflammatory cytokine production, and cancer maligancies. The findings of this study not only shed light on the role of CPAP in HBV-associated HCC, but also provide CPAP as a potential target for HBV-related HCC therapy.\n\nAuthor SummaryIn this study, we address a novel molecular mechanism for the collaboration between overexpressed HBx and CPAP in promoting hepatocarcinogenesis in HBV-associated HCC. Upon HBV infection, HBx is overexpressed and interacts with CREB to transcriptionally activate CPAP; the HBx/CPAP interaction promotes hepatocarcinogenesis. Clinical analysis found that co-overexpressed CPAP and CREB exist in the high-risk group with a lower survival rate in HCC. Additionally, overexpressed CPAP contributes to HBx protein stability in a NF-{kappa}B-dependent pathway. Our study provides a potential translational application in targeting CREB-CPAP axis in HBV-associated HCC.

cancer biology

A single-cell level and connectome-derived computational model of the Drosophila brain

Computer simulations play an important role in testing hypotheses, integrating knowledge, and providing predictions of neural circuit functions. While considerable effort has been dedicated into simulating primate or rodent brains, the fruit fly (Drosophila melanogaster) is becoming a promising model animal in computational neuroscience for its small brain size, complex cognitive behavior, and abundancy of data available from genes to circuits. Moreover, several Drosophila connectome projects have generated a large number of neuronal images that account for a significant portion of the brain, making a systematic investigation of the whole brain circuit possible. Supported by FlyCircuit (http://www.flycircuit.tw), one of the largest Drosophila neuron image databases, we began a long-term project with the goal to construct a whole-brain spiking network model of the Drosophila brain. In this paper, we report the outcome of the first phase of the project. We developed the Flysim platform, which 1) identifies the polarity of each neuron arbor, 2) predicts connections between neurons, 3) translates morphology data from the database into physiology parameters for computational modeling, 4) reconstructs a brain-wide network model, which consists of 20,089 neurons and 1,044,020 synapses, and 5) performs computer simulations of the resting state. We compared the reconstructed brain network with a randomized brain network by shuffling the connections of each neuron. We found that the reconstructed brain can be easily stabilized by implementing synaptic short-term depression, while the randomized one exhibited seizure-like firing activity under the same treatment. Furthermore, the reconstructed Drosophila brain was structurally and dynamically more diverse than the randomized one and exhibited both Poisson-like and patterned firing activities. Despite being at its early stage of development, this single-cell level brain model allows us to study some of the fundamental properties of neural networks including network balance, critical behavior, long-term stability, and plasticity.

bioinformatics

Molecular Basis Underlying Male Sterility In bHLH142 Overexpressing Rice

Development of stable male sterility lines is essential for efficient hybrid seed production. We previously showed that knockout of bHLH142 in rice (Oryza sativa) causes pollen sterility by interrupting tapetal programmed cell death (PCD). In this study, we demonstrated that overexpression of bHLH142 (OE142) under the control of ubiquitin promoter also leads to male sterility in rice by triggering the premature onset of PCD. Protein of bHLH142 was found to accumulate specifically in the OE142 anthers. Overexpression of bHLH142 induced early expression of several key regulatory transcription factors in pollen development. In particular, the upregulation of EAT1 at the early stage of pollen development promoted premature PCD in the OE142 anthers, while its downregulation at the late stage impaired pollen development by suppressing genes involved in pollen wall biosynthesis, ROS scavenging and PCD. Collectively, these events led to male sterility in OE142. Analyses of related mutants further revealed the hierarchy of these pollen development regulatory genes. Thus, the findings of this study create a new method to generate genic male sterility in rice. Exploitation of this novel functionality of bHLH142 would confer a big advantage to hybrid seed production.\n\nHighlightOverexpression of bHLH142 leads to male sterility in transgenic rice due to early onset of tapetal PCD. This study creates a new method to generate male sterility in rice.

molecular biology