Developmental expression of COE across the Metazoa supports a conserved role in neuronal cell-type specification and mesodermal development

The transcription factor COE (collier/olfactory-1/early B cell factor) is an unusual basic helix–loop–helix transcription factor as it lacks a basic domain and is maintained as a single copy gene in the genomes of all currently analysed non-vertebrate Metazoan genomes. Given the unique features of the COE gene, its proposed ancestral role in the specification of chemosensory neurons and the wealth of functional data from vertebrates and Drosophila, the evolutionary history of the COE gene can be readily investigated. We have examined the ways in which COE expression has diversified among the Metazoa by analysing its expression from representatives of four disparate invertebrate phyla: Ctenophora (Mnemiopsis leidyi); Mollusca (Haliotis asinina); Annelida (Capitella teleta and Chaetopterus) and Echinodermata (Strongylocentrotus purpuratus). In addition, we have studied COE function with knockdown experiments in S. purpuratus, which indicate that COE is likely to be involved in repressing serotonergic cell fate in the apical ganglion of dipleurula larvae. These analyses suggest that COE has played an important role in the evolution of ectodermally derived tissues (likely primarily nervous tissues) and mesodermally derived tissues. Our results provide a broad evolutionary foundation from which further studies aimed at the functional characterisation and evolution of COE can be investigated

Cleavage modification did not alter blastomere fates during bryozoan evolution

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.The study was funded by the core budget of the Sars Centre and by The European Research Council Community’s Framework Program Horizon 2020 (2014–2020) ERC grant agreement 648861 to A

The Tourist Area Life Cycle (TALC) and Its Effect on the Quality-of-Life (QOL) of Destination Community

This chapter examines the connection between tourism area life cycle (TALC) and its effects on the quality-of-life (QOL) of destination communities. We posit that as destinations go through structural changes over time, the extent to which the dynamics of change affect the QOL of the resident community varies with the stages of the life cycle. The chapter consists of four major sections. After a brief introduction, the first section presents the concept of TALC and describes the development phases and the indicators that help understand tourism area development. The second section provides a brief discussion on the impact of tourism on the community in relation to TALC, which is then followed by the third section which focuses on the adjustment to change and maintaining the QOL of the community. Section four reviews related literature to support the relation between TALC and QOL of communities. The chapter ends with delineating critical issues for future research, outlining some of the difficulties moving forward, and formulating relevant policy implications that may help the researchers and destination management organizations to further examine the issues that may surround TALC and QOL connections