Publications by authors named "Yan Y Yip"

Background: The high prevalence of noncommunicable diseases and the growing importance of social media have prompted health care professionals (HCPs) to use social media to deliver health information aimed at reducing lifestyle risk factors. Previous studies have acknowledged that the identification of elements that influence user engagement metrics could help HCPs in creating engaging posts toward effective health promotion on social media. Nevertheless, few studies have attempted to comprehensively identify a list of elements in social media posts that could influence user engagement metrics.

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Addressing timely community palliative care integration is prioritized due to the increased burden of noncommunicable diseases. To compare referral-to-death duration among palliative cancer and noncancer patients and to determine its associated factors in a Malaysian community palliative care center. This retrospective cohort study included decedents referred to a Malaysian community palliative care center between January 2017 and December 2019.

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The cargo-binding capabilities of cytoskeletal motor proteins have expanded during evolution through both gene duplication and alternative splicing. For the light chains of the kinesin-1 family of microtubule motors, this has resulted in an array of carboxyl-terminal domain sequences of unknown molecular function. Here, combining phylogenetic analyses with biophysical, biochemical, and cell biology approaches, we identify a highly conserved membrane-induced curvature-sensitive amphipathic helix within this region of a subset of long kinesin light-chain paralogs and splice isoforms.

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The light chains (KLCs) of the heterotetrameric microtubule motor kinesin-1, that bind to cargo adaptor proteins and regulate its activity, have a capacity to recognize short peptides via their tetratricopeptide repeat domains (KLC). Here, using X-ray crystallography, we show how kinesin-1 recognizes a novel class of adaptor motifs that we call 'Y-acidic' (tyrosine flanked by acidic residues), in a KLC-isoform-specific manner. Binding specificities of Y-acidic motifs (present in JIP1 and in TorsinA) to KLC1 are distinct from those utilized for the recognition of W-acidic motifs, found in adaptors, that are KLC-isoform non-selective.

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The microtubule motor kinesin-1 interacts via its cargo-binding domain with both microtubules and organelles, and hence plays an important role in controlling organelle transport and microtubule dynamics. In the absence of cargo, kinesin-1 is found in an autoinhibited conformation. The molecular basis of how cargo engagement affects the balance between kinesin-1's active and inactive conformations and roles in microtubule dynamics and organelle transport is not well understood.

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The molecular interplay between cargo recognition and regulation of the activity of the kinesin-1 microtubule motor is not well understood. Using the lysosome adaptor SKIP (also known as PLEKHM2) as model cargo, we show that the kinesin heavy chains (KHCs), in addition to the kinesin light chains (KLCs), can recognize tryptophan-acidic-binding determinants on the cargo when presented in the context of an extended KHC-interacting domain. Mutational separation of KHC and KLC binding shows that both interactions are important for SKIP-kinesin-1 interaction and that KHC binding is important for lysosome transport However, in the absence of KLCs, SKIP can only bind to KHC when autoinhibition is relieved, suggesting that the KLCs gate access to the KHCs.

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The spatial distribution of lysosomes is important for their function and is, in part, controlled by cellular nutrient status. Here, we show that the lysosome associated Birt-Hoge-Dubé (BHD) syndrome renal tumour suppressor folliculin (FLCN) regulates this process. FLCN promotes the peri-nuclear clustering of lysosomes following serum and amino acid withdrawal and is supported by the predominantly Golgi-associated small GTPase Rab34.

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The light chains (KLCs) of the microtubule motor kinesin-1 bind cargoes and regulate its activity. Through their tetratricopeptide repeat domain (KLC(TPR)), they can recognize short linear peptide motifs found in many cargo proteins characterized by a central tryptophan flanked by aspartic/glutamic acid residues (W-acidic). Using a fluorescence resonance energy transfer biosensor in combination with X-ray crystallographic, biochemical, and biophysical approaches, we describe how an intramolecular interaction between the KLC2(TPR) domain and a conserved peptide motif within an unstructured region of the molecule, partly occludes the W-acidic binding site on the TPR domain.

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Unlabelled: Malignant pleural mesothelioma (MPM) is often fatal, and studies have revealed that aberrant miRNAs contribute to MPM development and aggressiveness. Here, a screen of miRNAs identified reduced levels of miR-223 in MPM patient specimens. Interestingly, miR-223 targets Stathmin (STMN1), a microtubule regulator that has been associated with MPM.

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WD40-repeat protein 62 (WDR62) is a spindle pole protein required for normal cell division and neuroprogenitor differentiation during brain development. Microcephaly-associated mutations in WDR62 lead to mitotic mislocalization, highlighting a crucial requirement for precise WDR62 spatiotemporal distribution, although the regulatory mechanisms are unknown. Here, we demonstrate that the WD40-repeat region of WDR62 is required for microtubule association, whereas the disordered C-terminal region regulates cell-cycle-dependent compartmentalization.

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The stathmin (STMN) family of tubulin-binding phosphoproteins are critical regulators of interphase microtubule dynamics and organization in a broad range of cellular processes. c-Jun N-terminal kinase (JNK) signalling to STMN family proteins has been implicated specifically in neuronal maturation, degeneration and cell stress responses more broadly. Previously, we characterized mechanisms underlying JNK phosphorylation of STMN at proline-flanked serine residues (Ser25 and Ser38) that are conserved across STMN-like proteins.

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Dynamic microtubule changes after a cell stress challenge are required for cell survival and adaptation. Stathmin (STMN), a cytoplasmic microtubule-destabilizing phosphoprotein, regulates interphase microtubules during cell stress, but the signaling mechanisms involved are poorly defined. In this study ectopic expression of single alanine-substituted phospho-resistant mutants demonstrated that STMN Ser-38 and Ser-63 phosphorylation were specifically required to maintain interphase microtubules during hyperosmotic stress.

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The impact of aberrant centrosomes and/or spindles on asymmetric cell division in embryonic development indicates the tight regulation of bipolar spindle formation and positioning that is required for mitotic progression and cell fate determination. WD40-repeat protein 62 (WDR62) was recently identified as a spindle pole protein linked to the neurodevelopmental defect of microcephaly but its roles in mitosis have not been defined. We report here that the in utero electroporation of neuroprogenitor cells with WDR62 siRNAs induced their cell cycle exit and reduced their proliferative capacity.

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The JNKs (c-Jun N-terminal kinases) are stress-activated serine/threonine kinases that can regulate both cell death and cell proliferation. We have developed a cell system to control JNK re-expression at physiological levels in JNK1/2-null MEFs (murine embryonic fibroblasts). JNK re-expression restored basal and stress-activated phosphorylation of the c-Jun transcription factor and attenuated cellular proliferation with increased cells in G1/S-phase of the cell cycle.

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The Raf-1 protein kinase is a major activator of the ERK MAPK pathway, which links signaling by a variety of cell surface receptors to the regulation of cell proliferation, survival, differentiation and migration. Signaling by Raf-1 is regulated by a complex and poorly understood interplay between phosphorylation events and protein-protein interactions. One important mode of Raf-1 regulation involves the phosphorylation-dependent binding of 14-3-3 proteins.

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Introduction: Major physiological differences in the coagulation system of children compared to that of adults are well documented. We have previously investigated the age-related differences in response to Unfractionated Heparin (UFH). However, the impact of developmental haemostasis on more recent anticoagulant drugs is unknown.

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