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Biology subjects

Cheung, C. Y.

Publications and source records attributed to Cheung, C. Y..

3 recordsLinked to original sources

Single-cell RNA-sequencing of bronchoscopy specimens: development of a rapid, minimal-handling protocol

Single-cell RNA-sequencing (scRNA-seq) is an important tool for understanding disease pathophysiology, including airways diseases. Currently, the majority of scRNA-seq studies in airways diseases have used invasive methods (airway biopsy, surgical resection) which carry inherent risks and thus present a major limitation to scRNA-seq investigation of airway pathology. Bronchial brushing, where the airway mucosa is sampled using a cytological brush, is a viable, less invasive method of obtaining airway cells for scRNA-seq. Here we are describing the development of a rapid and minimal-handling protocol for preparing single cell suspensions from bronchial brush specimens for scRNA-seq. Our optimized protocol maximises cell recovery and cell quality, and may facilitate large-scale profiling of the airway transcriptome at single cell resolution. Lay abstractSingle-cell RNA-sequencing (scRNA-seq) measures the gene expression of individual cells, and may be useful for understanding disease processes. scRNA-seq may be used to investigate lung diseases, but using invasive methods such as biopsy or surgery limits our ability to conduct large research studies. Bronchial brushing, where a soft brush is used to collect cells from inside the lungs, is a safer method but we need a better way to isolate individual cells from the brush specimens. We developed a method that is faster and involves less handling of the specimens compared to other published methods. Our method may therefore be useful for conducting large scRNA-seq studies in lung diseases.

genomics↗

Associations between thinner retinal neuronal layers and suboptimal brain structural integrity: Are the eyes a window to the brain?

We investigated the extent to which measures of retinal neuronal thickness capture variability in the structural integrity of the brain in a large population-based cohort followed from birth to midlife. Using data from the Dunedin Multidisciplinary Health and Development Study (n=1037; analytic n=828, aged 45 years), we specifically tested for associations between optical coherence tomography-measured retinal neuronal layers and MRI-measured structural brain integrity. We found that Study members who had thinner retinal neuronal layers had thinner average cortex, smaller total cortical surface area, smaller subcortical grey matter volumes, larger volume of white matter hyperintensities as well as older looking brains. This suggests that retinal neuronal thickness reflects differences in midlife structural brain integrity consistent with accelerated cognitive decline and increased risk for later dementia, further supporting the proposition that the retina may be a biomarker of brain aging as early as midlife.

neuroscience↗

Unconventional tonicity-regulated nuclear trafficking of NFAT5 mediated by KPNB1, XPOT and RUVBL2

NFAT5 is the only known mammalian tonicity-responsive transcription factor functionally implicated in diverse physiological and pathological processes. NFAT5 activity is tightly regulated by extracellular tonicity but the underlying mechanisms remain elusive. We demonstrated that NFAT5 enters the nucleus via the nuclear pore complex. We also found that NFAT5 utilizes a non-canonical nuclear localization signal (NFAT5-NLS) for nuclear imports. siRNA screening revealed that karyopherin {beta}1 (KPNB1) drives nuclear import of NFAT5 via directly interacting with NFAT5-NLS. Proteomics analysis and siRNA screening further revealed that nuclear export of NFAT5 under hypotonicity is mediated by Exportin-T, and that it requires RuvB-Like AAA type ATPase 2 (RUVBL2) as an indispensable chaperone. Our findings have identified KPNB1 and RUVBL2 as key molecules responsible for the unconventional tonicity-regulated nucleocytoplasmic shuttling of NFAT5. These findings offer an opportunity for developing novel NFAT5 targeting strategies that are potentially useful for the treatment of diseases associated with NFAT5 dysregulation.

cell biology↗