The perception of rhythmic patterns is crucial for the recognition of words in spoken languages, yet it remains unclear how these patterns are represented in the brain. Here, we tested the hypothesis that rhythmic patterns are encoded by neural activity phase-locked to the temporal modulation of these patterns in the speech signal. To test this hypothesis, we analyzed EEGs evoked with long sequences of alternating syllables acoustically manipulated to be perceived as a series of different rhythmic groupings in English.
View Article and Find Full Text PDFLengthening and creaky voice are associated with prosodic finality in English. Listeners can use lengthening to identify both utterance-internal and final prosodic phrase boundaries and can use creak to locate utterance endings. Less is known about listeners' use of creak to locate internal prosodic boundaries and the relative importance assigned to duration and creak when both are present.
View Article and Find Full Text PDFMutated spliceosome components are recurrently being associated with perturbed tissue development and disease pathogenesis. Cephalophŏnus (cph), is a zebrafish mutant carrying an early premature STOP codon in the spliceosome component Prpf8 (pre-mRNA processing factor 8). Cph initially develops normally, but then develops widespread cell death, especially in neurons, and is embryonic lethal.
View Article and Find Full Text PDFBackground & Aims: Zebrafish mutants generated by ethylnitrosourea-mutagenesis provide a powerful tool for dissecting the genetic regulation of developmental processes, including organogenesis. One zebrafish mutant, "flotte lotte" (flo), displays striking defects in intestinal, liver, pancreas, and eye formation at 78 hours postfertilization (hpf). In this study, we sought to identify the underlying mutated gene in flo and link the genetic lesion to its phenotype.
View Article and Find Full Text PDFThe dual specificity phosphatase PTEN exerts its tumour suppressor and cell-migration regulatory functions by dephosphorylating the phospholipid substrate, phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P(3)), and phosphotyrosine protein substrates. PTEN functions are regulated by phospholipid binding, interactions with other cellular proteins and phosphorylation at multiple sites. Precisely, how the phosphorylation and binding events modulate PTEN activity and structure remains mostly unclear.
View Article and Find Full Text PDFMembers of the matrix metalloproteinase (MMP) family are important for the remodeling of the extracellular matrix in a number of biological processes including a variety of immune responses. Two members of the family, MMP2 and MMP9, are highly expressed in specific myeloid cell populations in which they play a role in the innate immune response. To further expand the repertoire of molecular reagents available to study zebrafish myeloid cell development, the matrix metalloproteinase 9 (mmp9) gene from this organism has been identified and characterized.
View Article and Find Full Text PDFThe pharyngeal arches give rise to multiple organs critical for diverse processes, including the thymus, thyroid and parathyroids. Several molecular regulators of thymus and thyroid organogenesis are strikingly conserved between mammals and zebrafish. However, land animals have parathyroids whereas fish have gills.
View Article and Find Full Text PDFThe zebrafish (Danio rerio) has emerged as an informative vertebrate model for developmental studies, particularly those employing genetic approaches such as mutagenesis and screening. Zebrafish myelopoiesis has recently been characterized, paving the way for the experimental strengths of this model organism to contribute to an improved understanding of the genetic regulation of myeloid development. Zebrafish have a multi-lineage myeloid compartment with two types of granulocyte (heterophil/neutrophil and eosinophil granulocytes), and monocyte/macrophages, each with characteristic morphological features and histochemical staining properties.
View Article and Find Full Text PDFThe zebrafish is a useful model organism for developmental and genetic studies. The morphology and function of zebrafish myeloid cells were characterized. Adult zebrafish contain 2 distinct granulocytes, a heterophil and a rarer eosinophil, both of which circulate and are generated in the kidney, the adult hematopoietic organ.
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