Circadian rhythms, which are ubiquitous and adaptive, occur across all species, from microbes to humans, in which they organize and modify behavior and physiology. timeless (tim) is a canonical clock gene. The core composition of the Drosophila melanogaster endogenous circadian clock has been extensively investigated; however, in lepidopteran insects, including Bombyx mori, the mechanism is complicated and little is known regarding the participation of tim in the negative feedback loop responsible for behavioral activities. To arrive at a comprehensive understanding of the role of tim in the B. mori endogenous circadian clock, we exploited the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 gene editing system. We attempted to elucidate the functions of tim in the circadian clock of B. mori using Bmtim mutants. The knockouts affected two circadian behavioral activities: adult emergence and embryo hatching rhythms. Quantitative real-time polymerase chain reaction results confirmed that tim-knockouts induced relative reductions in the expression levels, and thereby the oscillation amplitudes, of Bmper and Bmclk messenger RNAs during both the photophase and scotophase. Additionally, the daily rhythmic expression of Bmdbt was upregulated in the photophase and downregulated in the scotophase in a tim-knockout. Our study reveals that tim is integral to the B. mori circadian clock and may be involved in regulating eclosion and hatching rhythms.

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Wildlife is under intense pressure from trade, which most likely contributes to zoonotic diseases. The study explores the impact of zoonotic disease outbreaks on the wildlife trade of Ghana. This study provides an in-depth analysis of the trends of taxa trade and factors that influence trade from 1975 to 2018 by combining zoonotic disease data with data from the CITES database. Trade flow showed that reptiles were the most traded group, followed by birds, mammals, and amphibians. Species of the families Pythonidae, Dendrobatidae, Cercopithecidae, and Psittacidae were the most traded. The decade mean number of trade for 1997 to 2007 was the highest (n = 62) followed by 2008 to 2018 (n = 54.4). Most exporter countries that traded with Ghana are from Africa and importers from the United States of America, Europe and Asia. Continuous trade in reptiles and birds, especially the endangered pythons and psittacus species, could lead to their extinction in the wild. The outbreak of zoonotic diseases influenced the dynamics of the wildlife trade in Ghana as traders shifted their activities among taxa over a period of time. Because those taxa were observed to harbour zoonotic diseases and constitute high health risks when traded. Mammals' trade flow decreased with disease outbreaks over time, while reptiles increased. Early detection of zoonotic diseases and the adoption of an expanded education module on avoiding species capable of harbouring pathogens will most likely help reduce trade in wildlife.

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