Browsing by Author "Li, Hui"

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    Proteomic Effects of Magnesium Stress on Biofilm Associated Proteins Isolated from Cellulolytic Bacillus licheniformis YNP5-TSU
    O’Hair, Joshua A.; Li, Hui; Rangu, Mahesh; Thapa, Santosh; Yang, Yong; Fish, Tara; Bhatti, Sarabjit; Thannhauser, Theodore W.; Zhou, Suping (Longdom Group, 2019-11-29)
    Optimization of cellulase activity is vital for synthesizing the end-products of second generation biofuel production. The slightest change in fermentation parameters can reduce the secretion of necessary enzymes to degrade cellulosic biomass. Determining the ecological effects of certain key media components is essential to understand how bacterial species will respond in a fluid environment. For our experiment a cellulosic media was designed to enhance the industrially important thermophile, Bacillus licheniformis YNP5-TSU. After several attempts to simplify the carboxymethylcellulose (CMC) media composition, impaired biofilm maturation and cellulase activity was noticed. This negative artifact occurred only when magnesium sulphate was removed from media. To analyze the shift in gene expression caused by magnesium stress, biofilm associated proteins were extracted from both control (4.0 mM MgSO4) and magnesium depleted (0.0 mM MgSO4) media at 24 hr and 48 hr incubation periods. These proteins were quantified through isobaric labeling and raw data generated from nanoLC-MS/MS identified over 2,000 proteins from the Bacillus licheniformis YNP5-TSU proteome (NCBI accession number MEDD00000000). After statistical normalization and false discovery rate were calculated, a total of 161 proteins from magnesium depleted media and 238 proteins from control media were deemed statistically relevant. A closer look through STRING interconnected webs, data mining, and NCBI annotations revealed several up/down regulated proteins that had linkage to biofilm formation and cellulase secretion. In this study we are able to provide significant evidence that; (1) biofilm maturation and cellulase production are highly correlated and (2), their optimization is dependent on the expression of several key proteins.
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    Recurrent chimeric fusion RNAs in non-cancer tissues and cells
    Babiceanu, Mihaela; Qin, Fujun; Xie, Zhongqiu; Jia, Yuemeng; Lopez, Kevin; Janus, Nick; Facemire, Loryn; Kumar, Shailesh; Pang, Yuwei; Qi, Yanjun; Lazar, Iuliana M.; Li, Hui (2016-04-07)
    Gene fusions and their products (RNA and protein) were once thought to be unique features to cancer. However, chimeric RNAs can also be found in normal cells. Here, we performed, curated and analyzed nearly 300 RNA-Seq libraries covering 30 different non-neoplastic human tissues and cells as well as 15 mouse tissues. A large number of fusion transcripts were found. Most fusions were detected only once, while 291 were seen in more than one sample. We focused on the recurrent fusions and performed RNA and protein level validations on a subset. We characterized these fusions based on various features of the fusions, and their parental genes. They tend to be expressed at higher levels relative to their parental genes than the non-recurrent ones. Over half of the recurrent fusions involve neighboring genes transcribing in the same direction. A few sequence motifs were found enriched close to the fusion junction sites. We performed functional analyses on a few widely expressed fusions, and found that silencing them resulted in dramatic reduction in normal cell growth and/or motility. Most chimeras use canonical splicing sites, thus are likely products of 'intergenic splicing'. We also explored the implications of these non-pathological fusions in cancer and in evolution.