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Bae, Y.

Publications and source records attributed to Bae, Y..

3 recordsLinked to original sources

ATRAID, a genetic factor that regulates the clinical action of nitrogen-containing bisphosphonates on bone.

Nitrogen-containing bisphosphonates (N-BPs), such as alendronate, are the most widely prescribed medications for diseases involving bone, with nearly 200 million prescriptions written annually. Recently, widespread use of N-BPs has been challenged due to the risk of rare but traumatic side effects such as atypical femoral fracture (AFFs) and osteonecrosis of the jaw (ONJ). N-BPs bind to and inhibit farnesyl diphosphate synthase (FDPS), resulting in defects in protein prenylation. Yet it remains poorly understood what other cellular factors might allow N-BPs to exert their pharmacological effects. Here, we performed genome-wide studies in cells and patients to identify the poorly characterized gene, ATRAID. Loss of ATRAID function results in selective resistance to N-BP-mediated loss of cell viability and the prevention of alendronate-mediated inhibition of prenylation. ATRAID is required for alendronate inhibition of osteoclast function, and ATRAID-deficient mice have impaired therapeutic responses to alendronate in both postmenopausal and senile (old age) osteoporosis models. Lastly, we performed exome sequencing on patients taking N-BPs that suffered ONJ or an AFF. ATRAID is one of three genes that contain rare non-synonymous coding variants in patients with ONJ or AFF that is also differentially expressed in poor outcome groups of patients treated with N-BPs. We functionally validated this patient variation in ATRAID as conferring cellular hypersensitivity to N-BPs. Our work adds key insight into the mechanistic action of N-BPs and the processes that might underlie differential responsiveness to N-BPs in people. One Sentence SummaryATRAID is essential for responses to the commonly prescribed osteoporosis drugs nitrogen-containing bisphosphonates. OverlineBONE

genomics

Loop-mediated isothermal amplification assay for Enterococcus sp., E. coli and S. aureus in chicken

Bacterial chondronecrosis with osteomyelitis (BCO) is a major cause of lameness in broiler chicken, and results in serious economic losses worldwide. Although the pathogenesis mechanism leading to lameness is not entirely understood, some strains of Enterococcus sp., avian pathogenic Escherichia coli, or Staphylococcus aureus have been long recognized as important causative pathogens. To prevent the progression of Enterococcus sp., avian pathogenic E. coli, or S. aureus infections, we developed rapid, sensitive, and convenient diagnostic assays using loop-mediated isothermal amplification (LAMP). Entero-Common-LAMP assays were developed for a simultaneous detection of eight Enterococcus species. To target specific microorganisms, seven Entero-Specific-LAMP assays for E. faecalis, E. faecium, E. hirae, E. gallinarum, E. avium, E. durans and E. cecorum, and E. coli-LAMP and S. aureus-LAMP assays, were developed. Considering the prevalence and economic impact of Enterococcus sp., E. coli, and S. aureus, the developed ten different LAMP assays have a considerable potential as routine diagnostic methods in the field or in resource-limited environments.

microbiology

Deconvolution Of Subcellular Protrusion Heterogeneity And The Underlying Actin Regulator Dynamics From Live Cell Imaging

Cell protrusion is morphodynamically heterogeneous at the subcellular level. However, the mechanistic understanding of protrusion activities is usually based on the ensemble average of actin regulator dynamics at the cellular or population levels. Here, we establish a machine learning-based computational framework called HACKS (deconvolution of Heterogeneous Activity Coordination in cytosKeleton at a Subcellular level) to deconvolve the subcellular heterogeneity of lamellipodial protrusion in migrating cells. HACKS quantitatively identifies distinct subcellular protrusion phenotypes from highly heterogeneous protrusion activities and reveals their underlying actin regulator dynamics at the leading edge. Furthermore, it can identify specific subcellular protrusion phenotypes susceptible to pharmacological perturbation and reveal how actin regulator dynamics are changed by the perturbation. Using our method, we discovered accelerating protrusion phenotype in addition to fluctuating and periodic protrusions. Intriguingly, the accelerating protrusion was driven by the temporally coordinated actions between Arp2/3 and VASP: initiated by Arp2/3-mediated actin nucleation, and then accelerated by VASP-mediated actin elongation. We were able to confirm it by pharmacological perturbations using CK666 and Cytochalasin D, which specifically reduced strong accelerating protrusion activities. Taken together, we have demonstrated that HACKS allows us to discover the fine differential coordination of molecular dynamics underlying subcellular protrusion heterogeneity via a machine learning analysis of live cell imaging data.

cell biology