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High diversity and differential evolution profiles have been observed for DD34E/ Tc1 transposons; several families originating from these groups, such as DD34E/ ZB , DD34E/ SB , DD35E/ TR , DD36E/ IC, and DD38E/ IT , have been well defined. Even though Frisky , Tiang , Tsessebe, and Topi transposons have been identified in Anopheles gambiae , their taxonomic distribution and phylogenetic relationship in nature remain largely unknown. The evolutionary profiles of Frisky , Tiang , Tsessebe , and Topi homology transposons were investigated in the current study. In total, 254 homology transposons of Frisky , Tiang , Hob , Tsessebe, and Topi were obtained in 200 species by data mining. The phylogenetic tree revealed that these transposons were classified into five main clades (Frisky , Tiang , Hob , Tsessebe , and Topi) forming a monophyletic clade with 98% bootstrap support, belonging to the DD34E/ Tc1 group, and named as Skipper (SK). SK transposons show a wide distribution in animals; however, differential taxonomic distribution patterns were observed for the subfamilies of Frisky , Tiang , Hob , Tsessebe, and Topi ; extensive invasion of Frisky in animals was found, whereas Tiang , Hob , Tsessebe, and Topi were mainly detected in Diptera. SK elements share a similar structural organization and display high sequence identities across subfamilies. Evolutionary dynamics and structural analysis revealed that SK s in some species, such as Bombyx mori , Lordiphosa magnipectinata , Carassius gibelio , Triplophysa dalaica , and Silurus glanis , have recently evolved and present as intact copies, indicating that SK s in these genomes may be active. Together, these observations improve our understanding of the diversity of DD34E/ Tc1 transposons and their impacts on genome evolution in animals. [ABSTRACT FROM AUTHOR]

Simple Summary: Transposable elements (TEs) are mobile genetic elements that play vital role in defining and contributing to the size, shape and structure of both prokaryotic and eukaryotic genomes in nature. The piggyBac (PB), a superfamily of DNA transposons, has been isolated over the years from various organisms including insects, fungi and plants. These piggyBac transposon systems have high efficiency with a wide usage in the study of gene therapies, mutagenesis and transgenesis. Currently, there is limited information available on DNA transposons in small (compact) genomes of animals. Therefore, this study aims to annotate the PB transposons in small genomes of animals, revealing their evolution profiles in both vertebrate and invertebrate genomes. TEs, including DNA transposons, are major contributors of genome expansions, and have played a very significant role in shaping the evolution of animal genomes, due to their capacity to jump from one genomic position to the other. In this study, we investigated the evolution landscapes of PB transposons, including their distribution, diversity, activity and structure organization in 79 species of small (compact) genomes of animals comprising both vertebrate and invertebrates. Overall, 212 PB transposon types were detected from almost half (37) of the total number of the small genome species (79) investigated. The detected PB transposon types, which were unevenly distributed in various genera and phyla, have been classified into seven distinct clades or families with good bootstrap support (>80%). The PB transposon types that were identified have a length ranging from 1.23 kb to 9.51 kb. They encode transposases of approximately ≥500 amino acids in length, and possess terminal inverted repeats (TIRs) ranging from 4 bp to 24 bp. Though some of the transposon types have long TIRs (528 bp), they still maintain the consistent and reliable 4 bp target site duplication (TSD) of TTAA. However, PiggyBac-2_Cvir transposon originating from the Crassostrea virginica species exhibits a unique TSD of TATG. The TIRs of the transposons in all the seven families display high divergence, with a highly conserved 5′ end motif. The core transposase domains (DDD) were better conserved among the seven different families compared to the other protein domains, which were less prevalent in the vertebrate genome. The divergent evolution dynamics analysis also indicated that the majority of the PB transposon types identified in this study are either relatively young or old, with some being active. Additionally, numerous invasions of PB transposons were found in the genomes of both vertebrate and invertebrate animals. The data reveals that the PB superfamily is widely distributed in these species. PB transposons exhibit high diversity and activity in the small genomes of animals, and might play a crucial role in shaping the evolution of these small genomes of animals. [ABSTRACT FROM AUTHOR]

The study assessed 18 Polycyclic Aromatic Hydrocarbons (PAHs) in O. niloticus (Nile tilapia) sampled from an aquaculture cage (farm) and a wild catch. The PAHs in fish samples were analysed using Gas Chromatography-Mass Spectrometry. Four PAHs (in order of levels: Indeno [1,2,3-cd] pyrene > Anthracene > Perylene > Pyrene; 100-0.8 µg/kg) and only one PAH (Pyrene: 4 µg/kg) were detected in raw samples from the cage and wild catch respectively. Chargrilling significantly increased Pyrene levels after cooking (wild: 4-11 µg/kg; cage: 5-23 µg/kg, p <.05), and likewise Anthracene levels in cage samples (13-153 µg/kg) but decreased Indeno [1,2,3-cd] pyrene levels from 100 ± 20 to 1.2 ± 0.2 µg/kg in cage samples. Smoking significantly increased 13 to 15 PAH congeners' levels (from < 1.0 up to 340 µg/kg) and total PAHs (wild: 4 to 840 µg/kg; cage: 110 to 560 µg/kg), and decreased Indeno [1,2,3-cd] pyrene (100 to 1.3 µg/kg) in cage samples but showed no effect on Benzo [g, h, i] perylene and Dibenzo [a, h] anthracene levels in all samples. For smoked samples, Benzo [a] pyrene and PAH4 (Benzo [a] anthracene, Chrysene, Benzo [b] fluoranthene, and Benzo [a] pyrene) exceeded the respective maximum permissible limits of 2 µg/kg and 12 µg/kg, and significantly influenced the levels of carcinogenic PAHs (CPAH, 135-170 µg/kg). Nevertheless, the Excess Cancer Risk (ECR) estimates, from a conservative approach, were far below the threshold (10−4), implying that consuming smoked or grilled tilapia from the study site is safe. [ABSTRACT FROM AUTHOR]

The current study evaluated the inclusion of Pancreatin enzyme on growth performance, intestinal morphology, endogenous enzyme activity, and immunological responses in cockerels. A total of 480 d-old-Hy-line cockerels were randomly divided into 5 treatments, with 6 replicates, 16 birds per cage. Birds were given a standard corn-soybean-based (CD) starter and grower diet. Exogenous Pancreatin enzyme was supplemented at 0: 250; 500; 750, and 1000 mg/kg. Results demonstrated that Pancreatin supplementation did not affect (P > 0.05) the growth performance and duodenal enzyme activity of birds. However, the addition of Pancreatin enzyme at 500 mg/kg increased (P < 0.05) jejunal villus height at 42 d; duodenal crypt depth and jejunal crypt depth at 70 d. Pancreatin supplementation except 1000 mg/kg increased (P < 0.05) serum IgM but not IgA and IgG. Furthermore, Pancreatin supplementation had the potential to decrease jejunal pH, spleen gene expression, and antibodies titers against NDV. In conclusion, Pancreatin enzyme inclusion had no effect on cockerels' growth performance despite the variation found on the gut morphology. Pancreatin enzyme at intermediary amounts (500 and 750 mg/kg) showed a satisfactory serum immunoglobulin result but had the potential to modulate differently on the antibody titers against NDV and gene expression. [ABSTRACT FROM AUTHOR]

Both ZeBrafish (ZB), a recently identified DNA transposon in the zebrafish genome, and SB, a reconstructed transposon originally discovered in several fish species, are known to exhibit high transposition activity in vertebrate cells. Although a similar structural organization was observed for ZB and SB transposons, the evolutionary profiles of their homologs in various species remain unknown. In the present study, we compared their taxonomic ranges, structural arrangements, sequence identities, evolution dynamics, and horizontal transfer occurrences in vertebrates. In total, 629 ZB and 366 SB homologs were obtained and classified into four distinct clades, named ZB, ZB-like, SB, and SB-like. They displayed narrow taxonomic distributions in eukaryotes, and were mostly found in vertebrates, Actinopterygii in particular tended to be the major reservoir hosts of these transposons. Similar structural features and high sequence identities were observed for transposons and transposase, notably homologous to the SB and ZB elements. The genomic sequences that flank the ZB and SB transposons in the genomes revealed highly conserved integration profiles with strong preferential integration into AT repeats. Both SB and ZB transposons experienced horizontal transfer (HT) events, which were most common in Actinopterygii. Our current study helps to increase our understanding of the evolutionary properties and histories of SB and ZB transposon families in animals. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis (Mtb) possesses five type VII secretion systems (T7SS), virulence determinants that include the secretion apparatus and associated secretion substrates. Mtb strains deleted for the genes encoding substrates of the ESX-3 T7SS, esxG or esxH, require iron supplementation for in vitro growth and are highly attenuated in vivo. In a subset of infected mice, suppressor mutants of esxG or esxH deletions were isolated, which enabled growth to high titers or restored virulence. Suppression was conferred by mechanisms that cause overexpression of an ESX-3 paralogous region that lacks genes for the secretion apparatus but encodes EsxR and EsxS, apparent ESX-3 orphan substrates that functionally compensate for the lack of EsxG or EsxH. The mechanisms include the disruption of a transcriptional repressor and a massive 38- to 60-fold gene amplification. These data identify an iron acquisition regulon, provide insight into T7SS, and reveal a mechanism of Mtb chromosome evolution involving “accordion-type” amplification. [ABSTRACT FROM AUTHOR]

Purpose: This study explores Ghanaian views about accountability discharge by firms and government in the context of the nation's newly discovered oil and gas resources. The research focusses on a range of issues relating to stakeholder interaction, communication flows and the impact of decision-making on Ghanaian lives, as perceived by individuals on the ground. Design/methodology/approach: The paper adapts elements of legitimacy theory to interpret the outcome of a series of semi-structured interviews with members of key accountee and accountor groups including citizens and representatives of the state and private firms in the oil and gas industry in Ghana. Findings: The results indicate that rather than attempting to effect substantive accountability discharge, Ghana's government and oil and gas firms employ a wide range of legitimation strategies despite the apparently complete absence of the accountee power normally seen as driving the need for social contract repair. Research limitations/implications: The findings suggest that accountability discharge in Ghana is cursory at best, with several legitimising strategies in evidence. The representatives from state institutions appear to share some of the concerns, suggesting that the problems are entrenched and will require robust enforcement of a strengthened regulatory approach to effect meaningful change. Originality/value: This paper contributes to the literature on the discharge of institutional accountability by building on earlier conceptualisations of legitimacy theory to explore perceptions around a recent natural resource discovery. The analysis highlights grave concerns regarding the behaviour of state and corporate actors, one that runs counter to sub-Saharan African tradition. [ABSTRACT FROM AUTHOR]

TEs, including DNA transposons, are major contributors of genome expansions, and have played a very significant role in shaping the evolution of animal genomes, due to their capacity to jump from one genomic position to the other. In this study, we investigated the evolution landscapes of PB transposons, including their distribution, diversity, activity and structure organization in 79 species of small (compact) genomes of animals comprising both vertebrate and invertebrates. Overall, 212 PB transposon types were detected from almost half (37) of the total number of the small genome species (79) investigated. The detected PB transposon types, which were unevenly distributed in various genera and phyla, have been classified into seven distinct clades or families with good bootstrap support (>80%). The PB transposon types that were identified have a length ranging from 1.23 kb to 9.51 kb. They encode transposases of approximately ≥500 amino acids in length, and possess terminal inverted repeats (TIRs) ranging from 4 bp to 24 bp. Though some of the transposon types have long TIRs (528 bp), they still maintain the consistent and reliable 4 bp target site duplication (TSD) of TTAA. However, PiggyBac-2&#95;Cvir transposon originating from the Crassostrea virginica species exhibits a unique TSD of TATG. The TIRs of the transposons in all the seven families display high divergence, with a highly conserved 5' end motif. The core transposase domains (DDD) were better conserved among the seven different families compared to the other protein domains, which were less prevalent in the vertebrate genome. The divergent evolution dynamics analysis also indicated that the majority of the PB transposon types identified in this study are either relatively young or old, with some being active. Additionally, numerous invasions of PB transposons were found in the genomes of both vertebrate and invertebrate animals. The data reveals that the PB superfamily is widely distributed in these species. PB transposons exhibit high diversity and activity in the small genomes of animals, and might play a crucial role in shaping the evolution of these small genomes of animals.