25 research outputs found
Identification and Functional Analysis of Group A bHLH Transcription Factor in Ctenophore Bolinopsis mikado
Okinawa Institute of Science and Technology Graduate UniversityDoctor of Philosophydoctoral thesi
Vibrational Modes of C_<60> Fullerene Adsorbed on Si(100)2×1 Surface Studied by High-Resolution Electron-Energy-Loss Spectroscopy
We have measured the inelastic electron-energy-loss spectra of C_ on the Si(100)2x1 surface in the infra-red energy range. If C_ is evaporated 5Å (approximately half a monolayer) on Si(100), a strong energy loss peak appears at 65 meV, and weak peaks and shoulders at 72, 144, and 175 meV. In the 12Å thick film, additional weak peaks at 96, 160, and 189 meV become more apparent. Intensities of these peaks are comparable to those of thick films measured by infra-red absorption and by Raman scattering spectroscopies. Moreover, we have measured the angle dependence of the inelastic electron intensity. These results suggest appreciable interactions between C_ and the dangling bonds of Si surface
Mass spectrometry of short peptides reveals common features of metazoan peptidergic neurons
The evolutionary origins of neurons remain unknown. Although recent genome data of extant early-branching animals have shown that neural genes existed in the common ancestor of animals, the physiological and genetic properties of neurons in the early evolutionary phase are still unclear. Here, we performed a mass spectrometry-based comprehensive survey of short peptides from early-branching lineages Cnidaria, Porifera and Ctenophora. We identified a number of mature ctenophore neuropeptides that are expressed in neurons associated with sensory, muscular and digestive systems. The ctenophore peptides are stored in vesicles in cell bodies and neurites, suggesting volume transmission similar to that of cnidarian and bilaterian peptidergic systems. A comparison of genetic characteristics revealed that the peptide-expressing cells of Cnidaria and Ctenophora express the vast majority of genes that have pivotal roles in maturation, secretion and degradation of neuropeptides in Bilateria. Functional analysis of neuropeptides and prediction of receptors with machine learning demonstrated peptide regulation of a wide range of target effector cells, including cells of muscular systems. The striking parallels between the peptidergic neuronal properties of Cnidaria and Bilateria and those of Ctenophora, the most basal neuron-bearing animals, suggest a common evolutionary origin of metazoan peptidergic nervous systems