Publications by authors named "Ahhyun Kim"

Ubiquitin-like with PHD and RING finger domains 1 (UHRF1) is an essential protein involved in the maintenance of repressive epigenetic marks, ensuring epigenetic stability and fidelity. As an epigenetic regulator, UHRF1 comprises several functional domains (UBL, TTD, PHD, SRA, RING) that are collectively responsible for processes like DNA methylation, histone modification, and DNA repair. UHRF1 is a downstream effector of the RB/E2F pathway, which is nearly universally deregulated in cancer.

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Loss-of-function mutations at the retinoblastoma (RB1) gene are associated with increased mortality, metastasis, and poor therapeutic outcome in several cancers, including osteosarcoma. However, the mechanism(s) through which RB1 loss worsens clinical outcome remains understudied. Ubiquitin-like with PHD and Ring Finger domains 1 (UHRF1) has been identified as a critical downstream effector of the RB/E2F signaling pathway that is overexpressed in various cancers.

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The protein kinase ATR is activated at sites of DNA double-strand breaks where it plays important roles in promoting DNA end resection and regulating cell cycle progression. TOPBP1 is a multi BRCT repeat containing protein that activates ATR at DSBs. Here we have developed an experimental tool, the DMAX system, to study the biochemical mechanism for TOPBP1-mediated ATR signalling.

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TOPBP1 is an important scaffold protein that helps orchestrate the cellular response to DNA damage. Although it has been previously appreciated that TOPBP1 can form oligomers, how this occurs and the functional consequences for oligomerization were not yet known. Here, we use protein binding assays and other biochemical techniques to study how TOPBP1 self associates.

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Hamacanthins are a class of antibacterial bisindole alkaloids isolated from marine sponges. Based on structure-activity relationships and in silico MRSA PK binding analysis of these bisindole alkaloids, the authors designed new hamacanthin B derivatives and evaluated their antibacterial activities against drug-resistant pathogens. Racemates of the synthetic products were resolved into their enantiomers by chiral separation using a cellulose column, and antibacterial activities were compared.

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Background: The reticulocyte count is a good marker of erythropoietic activity of the bone marrow. In the mid-1990s, automated flow cytometric analysis replaced microscopy for the quantification of reticulocytes. Leukocytosis cases with an erroneously high reticulocyte count and a high immature reticulocyte fraction (IRF) have been reported.

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A giant cell tumor of the tendon sheath (GCTTS) is 1 of the most common soft-tissue tumors of the hand and wrist, while the 2nd most frequent site is the ankle-foot complex. Although various solid tumors can develop in the axilla, GCTTS has not yet been reported. We describe the sonographic appearance of GCTTS in the axilla.

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