Publications by authors named "Joseph Y Ong"

SPOP is a Cul3 substrate adaptor responsible for the degradation of many proteins related to cell growth and proliferation. Because mutation or misregulation of SPOP drives cancer progression, understanding the suite of SPOP substrates is important to understanding the regulation of cell proliferation. Here, we identify Nup153, a component of the nuclear basket of the nuclear pore complex, as a novel substrate of SPOP.

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Recombinant adeno-associated viral (AAV) vectors have emerged as prominent gene delivery vehicles for gene therapy. In the journey of an AAV vector, AAV vectors can be exposed to different proteolytic environments inside the production cells, during the cell lysis step, within the endosome, and finally inside the cell nucleus. The stability of a modified AAV serotype 2 (AAV2) capsid was evaluated via a proteolytic approach using trypsin and other proteases and both denaturing and non-denaturing analytical methods.

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Recombinant adeno-associated viral (AAV) vectors have emerged as prominent gene delivery vehicles for gene therapy. AAV capsid proteins determine tissue specificity and immunogenicity and play important roles in receptor binding, the escape of the virus from the endosome, and the transport of the viral DNA to the nuclei of target cells. Therefore, the comprehensive characterization of AAV capsid proteins is necessary for a better understanding of the vector assembly, stability, and transduction efficiency of AAV gene therapies.

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SPOP is a Cul3 substrate adaptor responsible for degradation of many proteins related to cell growth and proliferation. Because mutation or misregulation of SPOP drives cancer progression, understanding the suite of SPOP substrates is important to understanding regulation of cell proliferation. Here, we identify Nup153, a component of the nuclear basket of the nuclear pore complex, as a novel substrate of SPOP.

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The spontaneous l-isoaspartate protein modification has been observed to negatively affect protein function. However, this modification can be reversed in many proteins in reactions initiated by the protein-l-isoaspartyl (d-aspartyl) -methyltransferase (PCMT1). It has been hypothesized that an additional mechanism exists in which l-isoaspartate-damaged proteins are recognized and proteolytically degraded.

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Continuous culture systems allow for the controlled growth of microorganisms over a long period of time. Here, we develop a novel test for mutagenicity that involves growing yeast in continuous culture systems exposed to low levels of mutagen for a period of approximately 20 days. In contrast, most microorganism-based tests for mutagenicity expose the potential mutagen to the biological reporter at a high concentration of mutagen for a short period of time.

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Article Synopsis
  • The assembly of the bipolar mitotic spindle is a complex process that relies on various enzyme activities, particularly the phosphorylation of proteins, essential for regulating early mitotic spindle assembly.
  • The review discusses important kinases and phosphatases, as well as specific phosphorylation events that affect centriole duplication, centrosome maturation, and bipolar spindle formation.
  • It also covers techniques for studying kinase-substrate relationships and offers insights into the future of research on posttranslational modifications in this area.
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Cell division requires the assembly and organization of a microtubule spindle for the proper separation of chromosomes in mitosis and meiosis. Phase separation is an emerging paradigm for understanding spatial and temporal regulation of a variety of cellular processes, including cell division. Phase-separated condensates have been recently discovered at many structures during cell division as a possible mechanism for properly localizing, organizing, and activating proteins involved in cell division.

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Cell division is a highly regulated and carefully orchestrated process. Understanding the mechanisms that promote proper cell division is an important step toward unraveling important questions in cell biology and human health. Early studies seeking to dissect the mechanisms of cell division used classical genetics approaches to identify genes involved in mitosis and deployed biochemical approaches to isolate and identify proteins critical for cell division.

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Article Synopsis
  • Targeting the leukemia proliferation cycle is an effective strategy for developing treatments, but identifying new antileukemic drugs has been challenging due to a lack of suitable screening methods for suspension cells.
  • Researchers developed a high-throughput screening platform that uses chemical cell cycle profiling, allowing them to test 181,420 druglike compounds on leukemia cells.
  • This research led to the discovery of Leusin-1, a leukemia-specific inhibitor that effectively arrests cancer cells in the G2 phase and induces apoptosis, showing higher efficacy in acute lymphoblastic leukemia compared to other cancers and normal cells.
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