Search bioRxivSearch

Biology subjects

Lin, Y.-H.

Publications and source records attributed to Lin, Y.-H..

6 recordsLinked to original sources

A Chemically-triggered Transition from Conflict to Cooperation in Burying Beetles

Although interspecific competition has long been recognized as a major driver of trait divergence and adaptive evolution1-3, relatively little effort has focused on how it influences the evolution of intraspecific cooperation4-6. Here we identify the mechanism by which the perceived pressure of interspecific competition influences the transition from intraspecific conflict to cooperation in a facultative cooperatively breeding species, the Asian burying beetle Nicrophorus nepalensis. In their natural environment in central Taiwan, N. nepalensis are typically aggressive to conspecifics and only cooperate with others of their own species at critical carcass resources in the presence of blowflies, their primary competitors7. We demonstrate that beetles form larger groups and are more cooperative in carcass preparation in warmer environments where the pressure of interspecific competition with blowflies is highest8. To test the hypothesis that the presence of blowflies promotes beetle cooperation and to identify the mechanism by which this occurs, we manipulated blowfly larvae on carcasses in the lab. We not only found that beetles are more cooperative at carcasses when blowfly maggots have begun to digest the tissue, but that this social cooperation appears to be triggered by a single chemical cue-- dimethyl disulfide (DMDS)--emitted from carcasses consumed by blowflies but not from control carcasses lacking blowflies. Our results provide experimental evidence that interspecific competition promotes the transition from intraspecific conflict to cooperation in N. nepalensis via a surprisingly simple social chemical cue that is a reliable indicator of interspecific competition. This finding helps bridge the gap between the proximate and ultimate factors regulating the transition between cooperation and conflict and moves toward a more comprehensive understanding of the evolution of mechanisms governing intraspecific variation in social behaviour.

evolutionary biology

Eradication of ENO1-deleted Glioblastoma through Collateral Lethality

Inhibiting glycolysis remains an aspirational approach for the treatment of cancer. We recently demonstrated that SF2312, a natural product phosphonate antibiotic, is a potent inhibitor of the glycolytic enzyme Enolase with potential utility for the collateral lethality-based treatment of Enolase-deficient glioblastoma (GBM). However, phosphonates are anionic at physiological pH, limiting cell and tissue permeability. Here, we show that addition of pivaloyloxymethyl (POM) groups to SF2312 (POMSF) dramatically increases potency, leading to inhibition of glycolysis and killing of ENO1-deleted glioma cells in the low nM range. But the utility of POMSF in vivo is dose-limited by severe hemolytic anemia. A derivative, POMHEX, shows equipotency to POMSF without inducing hemolytic anemia. POMHEX can eradicate intracranial orthotopic ENO1-deleted tumors, despite sub-optimal pharmacokinetic properties. Taken together, our data provide in vivo proof-of-principal for collateral lethality in precision oncology and showcase POMHEX as a useful molecule for the study of glycolysis in cancer metabolism.\n\n\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=104 SRC=\"FIGDIR/small/331538_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (20K):\norg.highwire.dtl.DTLVardef@1b78ebcorg.highwire.dtl.DTLVardef@1fc0ccforg.highwire.dtl.DTLVardef@ad268corg.highwire.dtl.DTLVardef@1bdee32_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology

HDAC11 Suppresses the Thermogenic Program of Adipose Tissue via BRD2

Little is known about the biological function of histone deacetylase 11 (HDAC11), which is the lone class IV HDAC. Here, we demonstrate that deletion of HDAC11 in mice stimulates brown adipose tissue (BAT) formation and beiging of white adipose tissue (WAT). Consequently, HDAC11-deficient mice exhibit dramatically enhanced thermogenic potential and, in response to high fat feeding, attenuated obesity, insulin resistance, and hepatic steatosis. Ex vivo and cell-based assays revealed that HDAC11 catalytic activity suppresses the BAT transcriptional program, in both the basal state and in response to {beta}-adrenergic receptor signaling, through a mechanism that is dependent on physical association with BRD2, a bromodomain and extraterminal (BET) acetyl-histone binding protein. These findings define a novel epigenetic pathway for the regulation of energy homeostasis, and suggest potential for HDAC11-selective inhibitors for the treatment of obesity and diabetes.

molecular biology

SeqsLab: an integrated platform for cohort-based annotation and interpretation of genetic variants on Spark

SummarySeqsLab is a platform that helps researchers to easily annotate and interpret genetic variants derived from a large quantity of personal genomes. It provides an integrated interface to annotate the variants based on curated databases as well as in silico estimation on the effects of the variants. SeqsLab adopts the scalable cluster computing framework, Spark, and incorporates several customized algorithms to speed up the process of variant annotation and interpretation. The key features of SeqsLab include efficient annotation on large structural variations, diverse combinations of variant filters, easy incorporation with a vast amount of public databases, and scalable architecture of analyzing hundreds of human whole genomes simultaneously.\n\nAvailability and ImplementationSeqsLab is implemented with JAVA. The generated annotation will then be stored in Elasticsearch for real-time query and exploratory analysis. SeqsLab can be accessed by web browsers and is freely available at http://portal.seqslab.net/.\n\nContactchungtsai_su@atgenomix.com\n\nSupplementary informationSupplementary data are available at Bioinformatics online.

bioinformatics

A general method to predict the effect of single amino acid substitutions on enzyme catalytic activity

Over the past thirty years, site-directed mutagenesis has become established as one of the most powerful techniques to probe enzyme reaction mechanisms1-3. Substitutions of active site residues are most likely to yield significant perturbations in kinetic parameters, but there are many examples of profound changes in these values elicited by remote mutations4-6. Ortholog comparisons of extant sequences show that many mutations do not have profound influence on enzyme function. As the number of potential single natural amino acid substitutions that can be introduced in a protein of N amino acids in length by directed mutation is very large (19 * N), it would be useful to have a method to predict which amino acid substitutions are more likely to introduce significant changes in kinetic parameters in order to design meaningful probes into enzyme function. What is especially desirable is the identification of critical residues that do not contact the substrate directly, and may be remote from the active site.\n\nWe collected literature data reflecting the effects of 2,804 mutations on kinetic properties for 12 enzymes. These data along with characteristic predictors were used in a machine-learning scheme to train a classifier to predict the effect of mutation. Use of this algorithm allows one to predict with a 2.5-fold increase in precision, if a given mutation, made anywhere in the enzyme, will cause a decrease in kcat/Km value of [≥] 95%. The improved precision allows the experimentalist to reduce the number of mutations necessary to probe the enzyme reaction mechanism.

bioinformatics

Mupirocin-associated temporal changes in the nasal microbiota and host’s antimicrobial responses: A pilot study in healthy staphylococcal carriers

BackgroundHow mupirocin affects the human nasal microbiota over time remains uncharacterized.\n\nMethodsWe repeatedly sampled the anterior nares of four healthy staphylococcal carriers before and after mupirocin use. By sequencing bacterial 16S ribosomal cDNA, we characterized sequential changes in the carriage status, the nasal microbiota, and the hosts antimicrobial peptide expression up to 90 days after decolonization.\n\nResultsBefore mupirocin use, the nasal microbiota differed by the initial, culture-based staphylococcal carriage status, with Firmicutes (54.1%) being the most predominant in carriers and Proteobacteria (75.8%) in the only noncarrier. The nasal microbiota became less diverse (Shannon diversity: 1.33, 95% confidence interval [CI]: 1.06-1.54) immediately after decolonisation than that before decolonisation (1.78, 95%CI: 0.58-1.93). Based on results of differential abundance analysis, Firmicutes were significantly enriched (log2 fold changes [&ge;] 4, Benjamini-Hochberg adjusted P < .01) while Actinobacteria, particularly Corynbebacterium, were relatively depleted in samples from staphylococcal carriers. Results of nonmetric multidimensional scaling (NMDS) and constrained correspondence analysis (CCA) also suggested that the initial staphylococcal carriage status, human neutrophil peptide 1 levels, and sampling times were major contributors to the between-community dissimilarities (P for marginal permutation test: .014) though the significance attenuated when within-group correlation was considered (P for blocked permutation test: .047).\n\nConclusionThese findings suggest that large-scale investigations on antibiotic effects on the human nasal microbiota are warranted.

microbiology