Biology subjects

Liao, Y.-C.

Publications and source records attributed to Liao, Y.-C..

4 recordsLinked to original sources

bioRxiv2024

Spatial top-down proteomics for the functional characterization of human kidney

BackgroundThe Human Proteome Project has credibly detected nearly 93% of the roughly 20,000 proteins which are predicted by the human genome. However, the proteome is enigmatic, where alterations in amino acid sequences from polymorphisms and alternative splicing, errors in translation, and post-translational modifications result in a proteome depth estimated at several million unique proteoforms. Recently mass spectrometry has been demonstrated in several landmark efforts mapping the human proteoform landscape in bulk analyses. Herein, we developed an integrated workflow for characterizing proteoforms from human tissue in a spatially resolved manner by coupling laser capture microdissection, nanoliter-scale sample preparation, and mass spectrometry imaging. ResultsUsing healthy human kidney sections as the case study, we focused our analyses on the major functional tissue units including glomeruli, tubules, and medullary rays. After laser capture microdissection, these isolated functional tissue units were processed with microPOTS (microdroplet processing in one-pot for trace samples) for sensitive top-down proteomics measurement. This provided a quantitative database of 616 proteoforms that was further leveraged as a library for mass spectrometry imaging with near-cellular spatial resolution over the entire section. Notably, several mitochondrial proteoforms were found to be differentially abundant between glomeruli and convoluted tubules, and further spatial contextualization was provided by mass spectrometry imaging confirming unique differences identified by microPOTS, and further expanding the field-of-view for unique distributions such as enhanced abundance of a truncated form (1-74) of ubiquitin within cortical regions. ConclusionsWe developed an integrated workflow to directly identify proteoforms and reveal their spatial distributions. Where of the 20 differentially abundant proteoforms identified as discriminate between tubules and glomeruli by microPOTS, the vast majority of tubular proteoforms were of mitochondrial origin (8 of 10) where discriminate proteoforms in glomeruli were primarily hemoglobin subunits (9 of 10). These trends were also identified within ion images demonstrating spatially resolved characterization of proteoforms that has the potential to reshape discovery-based proteomics because the proteoforms are the ultimate effector of cellular functions. Applications of this technology have the potential to unravel etiology and pathophysiology of disease states, informing on biologically active proteoforms, which remodel the proteomic landscape in chronic and acute disorders.

biochemistry↗

bioRxiv2023

Lysosomal release of amino acids at ER three-way junctions regulates transmembrane and secretory protein mRNA translation

One-third of the mammalian proteome is comprised of transmembrane and secretory proteins that are synthesized on endoplasmic reticulum (ER). Here, we investigate the spatial distribution and regulation of mRNAs encoding these membrane and secretory proteins (termed "secretome" mRNAs) through live cell, single molecule tracking to directly monitor the position and translation states of secretome mRNAs on ER and their relationship to other organelles. Notably, translation of secretome mRNAs occurred preferentially near lysosomes on ER marked by the ER junction-associated protein, Lunapark. Knockdown of Lunapark reduced the extent of secretome mRNA translation without affecting translation of other mRNAs. Less secretome mRNA translation also occurred when lysosome function was perturbed by raising lysosomal pH or inhibiting lysosomal proteases. Secretome mRNA translation near lysosomes was enhanced during amino acid deprivation. Addition of the integrated stress response inhibitor, ISRIB, reversed the translation inhibition seen in Lunapark knockdown cells, implying an eIF2 dependency. Altogether, these findings uncover a novel coordination between ER and lysosomes, in which local release of amino acids and other factors from ER-associated lysosomes patterns and regulates translation of mRNAs encoding secretory and membrane proteins.

cell biology↗

bioRxiv2021

Hot water extract of Arthrospira maxima (AHWE) has broad-spectrum antiviral activity against RNA virus including coronavirus SARS-CoV2, and the antivirus spray application

The emergence and re-emergence of RNA virus outbreaks highlight the urgent need for the development of broad-spectrum antiviral agents. Arthrospira maxima has be used as a food source for a long time, and the protein or polysaccharide fractions were evidenced to have antiviral activity, therefore we examined the antiviral efficacy of hot water extract from Arthrospira maxima (AHWE), on Enterovirus 71 (EV71), Influenza virus, Herpes simplex virus (HSV), Respiratory syncytial virus (RSV), Ebola virus, and Coronavirus for antiviral spray application. In this study, we demonstrated that the AHWE shown 90 to 100% inhibition rate on the plaque formation of EV71, HSV-1, HSV-2, influenza virus, RSV, 229E and SARS-COV2 at virus attachment stage, and the long-lasting protection study also found while the AHWE was pre-exposed to the open air for more than 4 hours in plaque reduction assay. In addition, AHWE also had inhibitory effect on Ebola virus replication at 500 ug/ml. Finally, AHWE also shown no toxicity and skin sensitivity that imply it could be safe for future clinical use if approved by FDA. In conclusion, this study suggests that AHWE could be developed as a potential broad-spectrum antivirus spray product and therapeutic agent.

microbiology↗

bioRxiv2019

Vibrational behavior of psyllids (Hemiptera: Psylloidea): functional morphology and mechanisms

Vibrational behavior of psyllids was first documented more than six decades ago. Over the years, workers have postulated as to what the exact signal-producing mechanisms of psyllids might be but the exact mechanism has remained elusive. The aim of this study is to determine the specific signal-producing structures and mechanisms of the psyllids. Here we examine six hypotheses of signal-producing mechanisms from both previous and current studies that include: wing vibration, wing-wing friction, wing-thorax friction, wing-leg friction, leg-abdomen friction, and axillary sclerite-thorax friction. Through selective removal of possible signal producing structures and observing wing-beat frequency with a high-speed video recorder, six hypotheses were tested. Extensive experiments were implemented on the species Macrohomotoma gladiata Kuwayama, while other species belonging to different families, i.e., Trioza sozanica (Boselli), Mesohomotoma camphorae Kuwayama, Cacopsylla oluanpiensis (Yang), and Cacopsylla tobirae (Miyatake) were also examined to determine the potential prevalence of each signal-producing mechanism within the Psylloidea. Further, scanning electron microscopy (SEM) was used to examine possible rubbing structures. The result of high speed photography showed that wing-beating frequency did not match the dominant frequency of vibrational signals, resulting in the rejection of wing vibration hypothesis. As for the selective removal experiments, the axillary sclerite-thorax friction hypothesis is accepted and wing-thorax friction hypothesis is supported partially, while others are rejected. The SEM showed that the secondary axillary sclerite of forewing bears many protuberances that would be suitable for stridulation. In conclusion, the signal-producing mechanism of psyllids involves two sets of morphological structures. The first is stridulation between the axillary cord and anal area of the forewing. The second is stridulation between the axillary sclerite of the forewing and the mesothorax.

animal behavior and cognition↗