Evolution of an ancient protein function involved in organized multicellularity in animals.

To form and maintain organized tissues, multicellular organisms orient their mitotic spindles relative to neighboring cells. A molecular complex scaffolded by the GK protein-interaction domain (GKPID) mediates spindle orientation in diverse animal taxa by linking microtubule motor proteins to a marker protein on the cell cortex localized by external cues. Here we illuminate how this complex evolved and commandeered control of spindle orientation from a more ancient mechanism. The complex was assembled through a series of molecular exploitation events, one of which - the evolution of GKPID's capacity to bind the cortical marker protein - can be recapitulated by reintroducing a single historical substitution into the reconstructed ancestral GKPID. This change revealed and repurposed an ancient molecular surface that previously had a radically different function. We show how the physical simplicity of this binding interface enabled the evolution of a new protein function now essential to the biological complexity of many animals

Inhibition of YAP/TAZ-driven TEAD activity prevents growth of NF2-null schwannoma and meningioma.

Schwannoma tumours typically arise on the 8th cranial nerve and are mostly caused by loss of the tumour suppressor Merlin (NF2). There are no approved chemotherapies for these tumours and the surgical removal of the tumour carries a high risk of damage to the 8th or other close cranial nerve tissue. New treatments for schwannoma and other NF2-null tumours such as meningioma are urgently required. Using a combination of human primary tumour cells and mouse models of schwannoma, we have examined the role of the Hippo signalling pathway in driving tumour cell growth. Using both genetic ablation of the Hippo effectors YAP and TAZ as well as novel TEAD palmitoylation inhibitors, we show that Hippo signalling may be successfully targeted in vitro and in vivo to both block and, remarkably, regress schwannoma tumour growth. In particular, successful use of TEAD palmitoylation inhibitors in a pre-clinical mouse model of schwannoma points to their potential future clinical use. We also identify the cancer stem cell marker aldehyde dehydrogenase 1A1 (ALDH1A1) as a Hippo signalling target, driven by the TAZ protein in human and mouse NF2-null schwannoma cells, as well as in NF2-null meningioma cells, and examine the potential future role of this new target in halting schwannoma and meningioma tumour growth

Discovery of SQSTM1/p62-dependent P-bodies that regulate the NLRP3 inflammasome

Autophagy and ribonucleoprotein granules, such as P-bodies (PBs) and stress granules, represent vital stress responses to maintain cellular homeostasis. SQSTM1/p62 phase-separated droplets are known to play critical roles in selective autophagy; however, it is unknown whether p62 can exist as another form in addition to its autophagic droplets. Here, we found that, under stress conditions, including proteotoxicity, endotoxicity, and oxidation, autophagic p62 droplets are transformed to a type of enlarged PBs, termed p62-dependent P-bodies (pd-PBs). p62 phase separation is essential for the nucleation of pd-PBs. Mechanistically, pd-PBs are triggered by enhanced p62 droplet formation upon stress stimulation through the interactions between p62 and DDX6, a DEAD-box ATPase. Functionally, pd-PBs recruit the NLRP3 inflammasome adaptor ASC to assemble the NLRP3 inflammasome and induce inflammation-associated cytotoxicity. Our study shows that p62 droplet-to-PB transformation acts as a stress response to activate the NLRP3 inflammasome process, suggesting that persistent pd-PBs lead to NLRP3-dependent inflammation toxicity

Integrating Diverse Datasets Improves Developmental Enhancer Prediction

Gene-regulatory enhancers have been identified using various approaches, including evolutionary conservation, regulatory protein binding, chromatin modifications, and DNA sequence motifs. To integrate these different approaches, we developed EnhancerFinder, a two-step method for distinguishing developmental enhancers from the genomic background and then predicting their tissue specificity. EnhancerFinder uses a multiple kernel learning approach to integrate DNA sequence motifs, evolutionary patterns, and diverse functional genomics datasets from a variety of cell types. In contrast with prediction approaches that define enhancers based on histone marks or p300 sites from a single cell line, we trained EnhancerFinder on hundreds of experimentally verified human developmental enhancers from the VISTA Enhancer Browser. We comprehensively evaluated EnhancerFinder using cross validation and found that our integrative method improves the identification of enhancers over approaches that consider a single type of data, such as sequence motifs, evolutionary conservation, or the binding of enhancer-associated proteins. We find that VISTA enhancers active in embryonic heart are easier to identify than enhancers active in several other embryonic tissues, likely due to their uniquely high GC content. We applied EnhancerFinder to the entire human genome and predicted 84,301 developmental enhancers and their tissue specificity. These predictions provide specific functional annotations for large amounts of human non-coding DNA, and are significantly enriched near genes with annotated roles in their predicted tissues and lead SNPs from genome-wide association studies. We demonstrate the utility of EnhancerFinder predictions through in vivo validation of novel embryonic gene regulatory enhancers from three developmental transcription factor loci. Our genome-wide developmental enhancer predictions are freely available as a UCSC Genome Browser track, which we hope will enable researchers to further investigate questions in developmental biology. © 2014 Erwin et al

Deficient prepulse inhibition in schizophrenia detected by the multi-site COGS

BACKGROUND: Startle inhibition by weak prepulses (PPI) is studied to understand the biology of information processing in schizophrenia patients and healthy comparison subjects (HCS). The Consortium on the Genetics of Schizophrenia (COGS) identified associations between PPI and single nucleotide polymorphisms in schizophrenia probands and unaffected relatives, and linkage analyses extended evidence for the genetics of PPI deficits in schizophrenia in the COGS-1 family study. These findings are being extended in a 5-site “COGS-2” study of 1800 patients and 1200 unrelated HCS to facilitate genetic analyses. We describe a planned interim analysis of COGS-2 PPI data. METHODS: Eyeblink startle was measured in carefully screened HCS and schizophrenia patients (n=1402). Planned analyses of PPI (60 ms intervals) assessed effects of diagnosis, sex and test site, PPI-modifying effects of medications and smoking, and relationships between PPI and neurocognitive measures. RESULTS: 884 subjects met strict inclusion criteria. ANOVA of PPI revealed significant effects of diagnosis (p=0.0005) and sex (p<0.002), and a significant diagnosis × test site interaction. HCS > schizophrenia PPI differences were greatest among patients not taking 2(nd) generation antipsychotics, and were independent of smoking status. Modest but significant relationships were detected between PPI and performance in specific neurocognitive measures. DISCUSSION: The COGS-2 multi-site study detects schizophrenia-related PPI deficits reported in single-site studies, including patterns related to diagnosis, prepulse interval, sex, medication and other neurocognitive measures. Site differences were detected and explored. The target COGS-2 schizophrenia “endophenotype” of reduced PPI should prove valuable for identifying and confirming schizophrenia risk genes in future analyses

Zawartość antyoksydantów w wyciągach z jemioły (Viscum album L.), jodły (Taxus baccata L.), sosny (Pinus sylvestris L.) i cisu (Abies alba Mill.)

Imbalance between the intensity of oxidative processes (that induce the formation of reactive oxygen species) and counteracting antioxidant system is called oxidative stress. Most of the pathological changes in living organisms is associated with the processes of carcinogenesis induced by free radicals. State of equilibrium is maintained due to the presence of antioxidant enzymes (e.g. superoxide dismutase, peroxidase) and other biologically active substances such as glutathione, ascorbic acid and beta-carotene. These compounds enable the removal of reactive oxygen species in cells. The purpose of this study was to investigate the oxidative activity of mistletoe extracts and their potential hosts: fir and pine, and yew trees, which also have therapeutic properties. The results of performed analysis of enzymatic antioxidants (superoxide dismutase and peroxidase) lead to the conclusion that their activity in the tissues of mistletoe is much lower than in the tissues of fir, pine and yew. It was found, however, a much higher content of non-enzymatic antioxidants such as ascorbic acid, glutathione or beta- carotene in the tissues of mistletoe compared to other plants analyzed. Thus, extracts from mistletoe are a rich source of antioxidants easily assimilated to organisms receiving them.Zaburzenie równowagi między natężeniem procesów oksydacyjnych, które indukują powstawanie reaktywnych form tlenu a przeciwdziałającym mu systemem antyoksydacyjnym określa się mianem stresu oksydacyjnego. Większość zmian patologicznych w organizmach związana jest z procesami kancerogenezy indukowanymi działaniem wolnych rodników. Stan równowagi utrzymywany jest dzięki obecności enzymów antyoksydacyjnych (np. dysmutazy ponadtlenkowej, peroksydazy) oraz innych substancji biologicznie czynnych, takich jak np. glutation, kwas askorbinowy czy β-karoten. Związki te umożliwiają usuwanie nadmiaru reaktywnych form tlenu z komórek. Celem pracy było zbadanie aktywności oksydacyjnej ekstraktów jemioły oraz jej potencjalnych żywicieli, jodły i sosny oraz cisu, który również ma właściwości terapeutyczne. Przeprowadzone analizy zawartości enzymatycznych antyoksydantów (dysmutazy ponadtlenkowej i peroksydazy) pozwalają stwierdzić, iż ich aktywność w tkankach jemioły jest znacznie niższa niż w tkankach jodły, sosny i cisu. Stwierdzono jednak znacznie wyższą zawartość antyoksydantów nieenzymatycznych, tj. kwasu askorbinowego, glutationu czy β-karotenu w tkankach jemioły w stosunku do pozostałych analizowanych roślin. Ekstrakty z jemioły są więc bogatym źródłem antyoksydantów łatwo przyswajalnych dla pobierających je organizmów

Mating in the Closest Living Relatives of Animals Is Induced by a Bacterial Chondroitinase

We serendipitously discovered that the marine bacterium Vibrio fischeri induces sexual reproduction in one of the closest living relatives of animals, the choanoflagellate Salpingoeca rosetta. Although bacteria influence everything from nutrition and metabolism to cell biology and development in eukaryotes, bacterial regulation of eukaryotic mating was unexpected. Here, we show that a single V.&nbsp;fischeri protein, the previously uncharacterized EroS, fully recapitulates the aphrodisiac-like activity of live V.&nbsp;fischeri. EroS is a chondroitin lyase; although its substrate, chondroitin sulfate, was previously thought to be an animal synapomorphy, we demonstrate that S.&nbsp;rosetta produces chondroitin sulfate and thus extend the ancestry of this important glycosaminoglycan to the premetazoan era. Finally, we show that V.&nbsp;fischeri, purified EroS, and other bacterial chondroitin lyases induce S.&nbsp;rosetta mating at environmentally relevant concentrations, suggesting that bacteria likely regulate choanoflagellate mating in nature