Publications by authors named "Pearl L"

While there are always differences in children's input, it is unclear how often these differences impact language development - that is, are developmentally meaningful - and why they do (or do not) do so. We describe a new approach using computational cognitive modeling that links children's input to predicted language development outcomes, and can identify if input differences are potentially developmentally meaningful. We use this approach to investigate if there is developmentally-meaningful input variation across socio-economic status () with respect to the complex syntactic knowledge called syntactic islands.

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Background: Aborted bariatric surgeries are an undesirable experience for patients as they are subjected to potential physical harm and emotional distress. A thorough investigation of aborted bariatric surgeries has not been previously reported. This information may allow the discovery of opportunities to mitigate the risk of aborting some bariatric operations.

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Mutually exclusive loss-of-function alterations in gene pairs are those that occur together less frequently than may be expected and may denote a synthetically lethal relationship (SSL) between the genes. SSLs can be exploited therapeutically to selectively kill cancer cells. Here, we analysed mutation, copy number variation, and methylation levels in samples from The Cancer Genome Atlas, using the hypergeometric and the Poisson binomial tests to identify mutually exclusive inactivated genes.

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Activation of the replicative Mcm2-7 helicase by loading GINS and Cdc45 is crucial for replication origin firing, and as such for faithful genetic inheritance. Our biochemical and structural studies demonstrate that the helicase activator GINS interacts with TopBP1 through two separate binding surfaces, the first involving a stretch of highly conserved amino acids in the TopBP1-GINI region, the second a surface on TopBP1-BRCT4. The two surfaces bind to opposite ends of the A domain of the GINS subunit Psf1.

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Computational cognitive modeling is a tool we can use to evaluate theories of syntactic acquisition. Here, I review several models implementing theories that integrate information from both linguistic and non-linguistic sources to learn different types of syntactic knowledge. Some of these models additionally consider the impact of factors coming from children's developing non-linguistic cognition.

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The purpose of this case is to highlight a rare case of sigmoid colon-to-rectum fistula. A 66-year-old man with a history of pelvic radiation and diverticulosis presented to the emergency department with a 3-week history of abdominal pain and watery diarrhea. Computed tomography (CT) imaging was significant for a sigmoid-to-rectum fistula with sigmoid stricture.

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Pneumopericardium is an exceptionally uncommon phenomenon in the setting of blunt polytrauma. It is imperative for trauma providers to identify tension pneumopericardium despite its rarity. A 22-year-old male motorcyclist presented to the hospital after colliding with a car going approximately 50 mph.

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Activation of client protein kinases by the HSP90 molecular chaperone system is affected by phosphorylation at multiple sites on HSP90, the kinase-specific co-chaperone CDC37, and the kinase client itself. Removal of regulatory phosphorylation from client kinases and their release from the HSP90-CDC37 system depends on the Ser/Thr phosphatase PP5, which associates with HSP90 via its N-terminal TPR domain. Here, we present the cryoEM structure of the oncogenic protein kinase client BRAF bound to HSP90-CDC37, showing how the V600E mutation favours BRAF association with HSP90-CDC37.

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Detection of cytosolic DNA is a central element of the innate immunity system against viral infection. The Ku heterodimer, a component of the NHEJ pathway of DNA repair in the nucleus, functions as DNA sensor that detects dsDNA of viruses that replicate in the cytoplasm. Vaccinia virus expresses two proteins, C4 and C16, that inactivate DNA sensing and enhance virulence.

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Objective: To determine the accuracy of adult height prediction in children with constitutional tall stature.

Methods: The medical records of 138 non-syndromatic prepubertal and early pubertal children (52 male, 86 female) with a height of ≥90 percentile born between the years 1975 and 1988 were included in this study. Using the Bayley-Pinneau (BP) and Tanner-Whitehouse I (TWI) prediction methods, their height standard deviation score (SDS) at referral was compared with their height SDS at age 17 years when measured at the IDF conscription center.

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The RAD9-RAD1-HUS1 (9-1-1) clamp forms one half of the DNA damage checkpoint system that signals the presence of substantial regions of single-stranded DNA arising from replication fork collapse or resection of DNA double strand breaks. Loaded at the 5'-recessed end of a dsDNA-ssDNA junction by the RAD17-RFC clamp loader complex, the phosphorylated C-terminal tail of the RAD9 subunit of 9-1-1 engages with the mediator scaffold TOPBP1 which in turn activates the ATR kinase, localised through the interaction of its constitutive partner ATRIP with RPA-coated ssDNA. Using cryogenic electron microscopy (cryoEM) we have determined the structure of a complex of the human RAD17-RFC clamp loader bound to human 9-1-1, engaged with a dsDNA-ssDNA junction.

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The cellular response to DNA damage (DDR) that causes replication collapse and/or DNA double strand breaks, is characterised by a massive change in the post-translational modifications (PTM) of hundreds of proteins involved in the detection and repair of DNA damage, and the communication of the state of damage to the cellular systems that regulate replication and cell division. A substantial proportion of these PTMs involve targeted phosphorylation, which among other effects, promotes the formation of multiprotein complexes through the specific binding of phosphorylated motifs on one protein, by specialised domains on other proteins. Understanding the nature of these phosphorylation mediated interactions allows definition of the pathways and networks that coordinate the DDR, and helps identify new targets for therapeutic intervention that may be of benefit in the treatment of cancer, where DDR plays a key role.

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During the human papillomavirus 16 (HPV16) life cycle, the E2 protein interacts with host factors to regulate viral transcription, replication, and genome segregation/retention. Our understanding of host partner proteins and their roles in E2 functions remains incomplete. Here we demonstrate that CK2 phosphorylation of E2 on serine 23 promotes interaction with TopBP1 and and that E2 is phosphorylated on this residue during the HPV16 life cycle.

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The R2TP (RUVBL1-RUVBL2-RPAP3-PIH1D1) complex, in collaboration with heat shock protein 90 (HSP90), functions as a chaperone for the assembly and stability of protein complexes, including RNA polymerases, small nuclear ribonucleoprotein particles (snRNPs), and phosphatidylinositol 3-kinase (PI3K)-like kinases (PIKKs) such as TOR and SMG1. PIKK stabilization depends on an additional complex of TELO2, TTI1, and TTI2 (TTT), whose structure and function are poorly understood. The cryoelectron microscopy (cryo-EM) structure of the human R2TP-TTT complex, together with biochemical experiments, reveals the mechanism of TOR recruitment to the R2TP-TTT chaperone.

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CHK1 is a protein kinase that functions downstream of activated ATR to phosphorylate multiple targets as part of intra-S and G2/M DNA damage checkpoints. Its role in allowing cells to survive replicative stress has made it an important target for anti-cancer drug discovery. Activation of CHK1 by ATR depends on their mutual interaction with CLASPIN, a natively unstructured protein that interacts with CHK1 through a cluster of phosphorylation sites in its C-terminal half.

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BLM (Bloom syndrome protein) is a RECQ-family helicase involved in the dissolution of complex DNA structures and repair intermediates. Synthetic lethality analysis implicates BLM as a promising target in a range of cancers with defects in the DNA damage response; however, selective small molecule inhibitors of defined mechanism are currently lacking. Here, we identify and characterise a specific inhibitor of BLM's ATPase-coupled DNA helicase activity, by allosteric trapping of a DNA-bound translocation intermediate.

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The key aim of this special issue is to make developmental theory proposals concrete enough to evaluate with empirical data. With this in mind, I discuss proposals from the "Universal Grammar + statistics" (UG+stats) perspective for learning several morphology and syntax phenomena. I briefly review why UG has traditionally been part of many developmental theories of language, as well as common statistical learning approaches that are part of UG+stats proposals.

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Elucidating signaling driven by lemur tyrosine kinase 3 (LMTK3) could help drug development. Here, we solve the crystal structure of LMTK3 kinase domain to 2.1Å resolution, determine its consensus motif and phosphoproteome, unveiling in vitro and in vivo LMTK3 substrates.

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Heat shock protein 90 (Hsp90) is a molecular chaperone that plays an important role in tumour biology by promoting the stabilisation and activity of oncogenic 'client' proteins. Inhibition of Hsp90 by small-molecule drugs, acting via its ATP hydrolysis site, has shown promise as a molecularly targeted cancer therapy. Owing to the importance of Hop and other tetratricopeptide repeat (TPR)-containing cochaperones in regulating Hsp90 activity, the Hsp90-TPR domain interface is an alternative site for inhibitors, which could result in effects distinct from ATP site binders.

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The number of high-resolution structures of protein complexes obtained using cryo-electron microscopy (cryo-EM) is increasing rapidly. Cryo-EM maps of large macromolecular complexes frequently contain regions resolved at different resolution levels, and modeling atomic structures can be difficult for domains determined at worse than 5 Å in the absence of atomic information from other structures. Here we describe the details and step-by-step decisions in the strategy we followed to model the RUVBL2-binding domain (RBD), a 14 kDa domain at the C-terminus of RNA Polymerase II associated protein 3 (RPAP3) for which atomic information was not available.

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Coordination of the cellular response to DNA damage is organised by multi-domain 'scaffold' proteins, including 53BP1 and TOPBP1, which recognise post-translational modifications such as phosphorylation, methylation and ubiquitylation on other proteins, and are themselves carriers of such regulatory signals. Here we show that the DNA damage checkpoint regulating S-phase entry is controlled by a phosphorylation-dependent interaction of 53BP1 and TOPBP1. BRCT domains of TOPBP1 selectively bind conserved phosphorylation sites in the N-terminus of 53BP1.

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The human R2TP complex (RUVBL1-RUVBL2-RPAP3-PIH1D1) is an HSP90 co-chaperone required for the maturation of several essential multiprotein complexes, including RNA polymerase II, small nucleolar ribonucleoproteins, and PIKK complexes such as mTORC1 and ATR-ATRIP. RUVBL1-RUVBL2 AAA-ATPases are also primary components of other essential complexes such as INO80 and Tip60 remodelers. Despite recent efforts, the molecular mechanisms regulating RUVBL1-RUVBL2 in these complexes remain elusive.

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In mitosis, cells inactivate DNA double-strand break (DSB) repair pathways to preserve genome stability. However, some early signaling events still occur, such as recruitment of the scaffold protein MDC1 to phosphorylated histone H2AX at DSBs. Yet, it remains unclear whether these events are important for maintaining genome stability during mitosis.

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XRCC1 accelerates repair of DNA single-strand breaks by acting as a scaffold protein for the recruitment of Polβ, LigIIIα, and end-processing factors, such as PNKP and APTX. XRCC1 itself is recruited to DNA damage through interaction of its central BRCT domain with poly(ADP-ribose) chains generated by PARP1 or PARP2. XRCC1 is believed to interact directly with DNA at sites of damage, but the molecular basis for this interaction within XRCC1 remains unclear.

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