Gene Cytochrome Research Articles

The Role of Skunks in the Epidemiology of Rabies in the State of Yucatan from 2000 to 2022: Current Perspectives and Future Research Directions

In 2019, the World Health Organization (WHO) and the Pan American Health Organization (PAHO) bestowed upon Mexico the status of a country free from canine-transmitted human rabies; however, the lingering public health challenge in the nation continues to be the sylvatic cycle of rabies. In Mexico, skunks play a significant role as reservoirs for four antigenic variants of the rabies virus. Nonetheless, up to this point, the specific skunk species involved in this cycle had not been accurately established. This study (2002–2022) aims to identify the taxonomy of skunk specimens diagnosed as rabies-positive in the state of Yucatan, in order to determine the species that serves as the reservoir for the Yucatan sylvatic lineage of rabies. This was achieved through the sequencing of an approximately 680 bp fragment of the mitochondrial gene cytochrome B. All samples belong to the species Spilogale angustifrons yucatanensis. This discovery offers valuable information for understanding and managing the wildlife rabies cycle in Mexico. It also contributes to an improved understanding of the taxonomy within the genus Spilogale.

DNA Barcoding of Tabanids (Diptera: Tabanidae) from Veracruz, Mexico, with Notes on Morphology and Taxonomy

(1) Background: Tabanids are one of the most neglected and difficult-to-identify groups within the order Diptera despite their medical–veterinary importance. Since 2010, DNA barcoding has proved to be a promising method for the identification of horseflies in the Old World, but until now it had explored little with regards to Neotropical species. In Mexico, faunal studies continue to be focused on certain regions of the country, which has limited the generation of taxonomic keys. Here, we employed the DNA barcoding approach to contribute to the knowledge of horsefly species in one of the least explored biogeographic provinces in Mexico, the state of Veracruz. (2) Methods: Tabanids were collected at two localities using Malaise traps during two seasons. With a sampling effort of 300 h per trap per site, a total of 22 specimens were collected and identified using taxonomic keys and partial amplification and sequencing of the mitochondrial gene cytochrome c oxidase subunit 1 (COI). (3) Results: Five species of the Tabanus genus were identified through taxonomic keys, and three of these species were confirmed through molecular analyses: T. oculus, T. commixtus, and T. pungens. (4) Conclusions: This is the first contribution of the sequence data of the Tabanidae family for Mexico and demonstrates that DNA barcoding is a vital tool for the recognition of Neotropical species.

Eriophyes pouteriae sp. nov., a New Mite Species Infesting Pouteria sapota.

Pouteria sapota, or "mamey sapote", is a tropical fruit tree native to Central America and Southern Mexico, producing sweet, nutrient and vitamin-rich fruit. Several insect pests are known to infest P. sapota, but none have been associated with plant growth alterations. Eriophyoid mites are well known to cause plant malformations, but mites that cause this type of damage to mamey sapote have not been reported. Trees with abnormal leaf growth, including stunted leaves, outward curling, leaf yellowing, and diminishing overall tree vigor, were found in multiple locations in Southern Florida and one location in Brazil. Numerous plant samples were examined for the presence of minute eriophyoid-like mites, and a new species was found. It was morphologically described, and DNA fragments of the mitochondrial gene cytochrome c oxidase subunit I (COI), the nuclear subunit D2 region in 28S rDNA, and the ITS nuclear regions were PCR-amplified and sequenced. Morphological and molecular descriptions of the new species, named E. pouteriae sp. nov., are provided to aid the identification and future detection of this mite. Even though several species within the genus Eriophyes have been reported on other Sapotaceae species, this is the first eriophyoid mite known to be associated with mamey sapote.

Applying a cytochrome c oxidase I barcode for Leishmania species typing.

Species delimitation has always been a challenge for taxonomists and for Leishmania studies there is no exception. Herein we attempt to display the usefulness of the mitochondrial gene Cytochrome Oxidase I-coI in classical and barcode-based approaches for Leishmania characterization. A total of 228 samples were analyzed, comprising 28 Leishmania related taxa, mainly from cultures of the Oswaldo Cruz Foundation`s Leishmania Collection. Primers were designed for amplification of coI; sequences were analyzed by distance-based indicators and both the Neighbor Joining and NeighborNet as species grouping techniques. Automatic Barcode Gap Discovery was applied to define species delimitation while for the character-based analysis a software for Barcoding with Logic formulas was employed. Final sequences of 486 bp with 238 parsimonious sites were aligned and edited. Robust groups were formed for most of the genus species, distinctive nucleotide positions in the barcode sequence were observed for 11 of them. A good agreement between the techniques applied and the original characterization was observed. Few species were not distinguished by coI: (i) L. (V.) peruviana, L. (V.) lindenbergi, and L. (V.) utingensis; (ii) L. (L.) venezuelensis and (iii) L. colombiensis and L. equatorensis with identical sequences. Some of these taxa have been, at one time or another, classified as controversial and, for most of them, a higher number of isolates should be studied to properly infer their taxonomic status. CoI represents a mitochondrial target that stands out as a taxonomically important asset with multiple advantages over other genes. This paper corresponds to the first report of coI analysis in Leishmania, a potentially advantageous target for the characterization of this parasite.

Phylogeography of the Invasive Fruit Fly Species Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae) in South America.

The carambola fruit fly, Bactrocera carambolae Drew & Hancock, is native to Southeast Asia, infests about 150 plant species, and is considered a quarantine pest insect in several regions of the world. Bactrocera carambolae has invaded Suriname, French Guyana, and northern Brazil. In Brazil, it was first recorded in 1996 and has been restricted to the states of Amapá and Roraima due to official control efforts of the Ministry of Agriculture and Food Supply (Ministério da Agricultura e Pecuária-MAPA). This is the first study to estimate the genetic structure and diversity of South American populations of B. carambolae. A total of 116 individuals from 11 localities in Brazil and 7 localities in Suriname were analyzed. Additional sequences available at GenBank from Indonesia (Lampung) and Thailand (San Pa Tong and Muang District) were also used in the analysis. We sequenced a fragment of the mitochondrial gene cytochrome oxidase subunit I. A total of 35 haplotypes were found. Haplotypes from Indonesia were closest to the haplotypes from South America, separated only by a few mutational steps. This suggests that Indonesia is the likely source for the introduction of B. carambolae into South America. The Southeast Asian populations appeared as the most ancestral group in the phylogenetic trees. The high similarity and sharing of several haplotypes among populations within South America indicate a lack of genetic structure. The mismatch distribution and neutrality tests suggest that South American populations have undergone a rapid growth and expansion following a single founder event. The low genetic diversity and the population expansion evidenced by the neutrality tests lend support to the hypothesis of a recent introduction of a single lineage of the carambola fruit fly into South America.

First molecular evidence of Penthaleus major (Dugés) (Penthaleidae) in Brazil

Penthaleus major (Dugés) (Penthaleidae) is an invasive pest in Brazil, first detected in 2009, attacking oat plants in Rio Grande do Sul, southern Brazil. This pest went unnoticed for almost 12 years until 2020 when suspected specimens of a blue mite were collected on oat plants in the municipalities of André da Rocha and Cachoeira do Sul, Rio Grande do Sul state, Brazil. Genomic DNA was extracted from these specimens and used for PCR amplification of a region of the mitochondrial gene Cytochrome Oxidase I (COI). The amplified fragments were sequenced, and the genetic sequences obtained were compared with those in GenBank. The results confirm, for the first time, the presence of the species P. major in Brazil using DNA barcoding. Further analysis revealed the presence of a single and specific haplotype in the country, suggesting either a single invasion or multiple invasions with the same maternal lineage.

Therapeutic effects of melatonin on the lungs of rats exposed to passive smoking

BackgroundPassive smoke has a significant impact on lung function and constitutes a critical public health issue, as smoking generates free radicals that damage the lungs and other tissues. Currently, limited research exists on whether the antioxidant melatonin can mitigate lung damage caused by smoking. This study aims to investigate the mechanisms through which melatonin alleviates acute lung disease induced by passive smoking.MethodsRats were divided into five groups (n = 6): a control group and three groups exposed to low, medium, and high concentrations of smoke, and a melatonin treatment group.ResultsData indicated that in the high concentration passive smoking group, the alveolar structure of the lung tissue was destroyed, and the total antioxidant capacity in lung tissue diminished as the concentration of smoke increased. The expressions of TNF-α, IL-6, and IL-1β exhibited similar results. The anti-apoptotic factors Bcl-2 and Bcl-xL mRNA level significantly decreased in the high concentration smoking group, while no significant changes were observed in the medium and low concentration groups. Conversely, the high concentration passive smoking increased the pro-apoptotic factors Bax and Caspase-3 mRNA levels. Additionally, endogenous melatonin levels in lung tissue gradually decreased following exposure to smoke, whereas the exogenous melatonin alleviated the changes in inflammatory factors and apoptosis-related factors in lung tissue. Furthermore, at high smoking concentrations, the mRNA levels of lung cancer-related genes vascular endothelial growth factor (VEGF), cytochromeP450 1A1 (CYP1A1), and cytochrome P450 1B1 (CYP1B1) were significantly increased, while exogenous melatonin reduced the expression of these genes in lung tissue.ConclusionsThese findings suggest that melatonin can diminish lung tissue damage, apoptosis, and inflammatory responses induced by passive smoking, as well as decrease the expression of lung cancer-related genes. Further experimental investigations involving exogenous melatonin treatments will be needed.

Global Invasion of Thrips parvispinus (Karny) (Thysanoptera: Thripidae) Across Three Continents Associated With Its One Haplotype

ABSTRACTThrips parvispinus (Karny) is an exotic pest that has invaded many regions around the world in the last three decades. It was first detected in Florida in 2020 on ornamental plants (Hoya and Anthurium) in greenhouses and subsequently on ornamental plants in residential landscapes (Gardenia) in 2021. However, its first report on open vegetable field crops (Capsicum) in Florida was in 2022. We conducted field surveys and genetic analysis to answer three questions: (1) Is the population of T. parvispinus that invaded Florida the same as the one that has spread globally in the last few decades? (2) Is the host expansion to Capsicum in Florida a new population or the extension of the existing population reported on ornamental plants? and (3) What are the native and invaded distribution ranges of T. parvispinus? We analysed the genetic variation in the mitochondrial gene cytochrome oxidase I (COI) to address these questions. The global genetic diversity analysis of T. parvispinus revealed 18 haplotypes (populations) worldwide based on available data, but only one population (Hap1) invaded three continents: Africa, Europe, and North America. Based on available data, the highest haplotype diversity was observed in India, suggesting India may be part of the presumed native range (South and Southeast Asian countries) of T. parvispinus. Our survey of retail plant stores across 10 Florida counties indicated that plant trade is the source of T. parvispinus in open vegetable field crops and ornamental landscape plants. The outcome of this study will assist with regulatory and management decisions of T. parvispinus in Florida and elsewhere.

Comparative Phylogeography of Two Specialist Rodents in Forest Fragments in Kenya.

The fragmented forests of the Kenya highlands, known for their exceptional species richness and endemism, are among the world's most important biodiversity hotspots. However, detailed studies on the fauna of these ecosystems-especially specialist species that depend on moist forests, which are particularly threatened by habitat fragmentation-are still limited. In this study, we used mitochondrial genes (cytochrome b and the displacement loop) and a nuclear marker (retinol-binding protein 3) to investigate genetic and morphological diversity, phylogenetic associations, historical divergence, population dynamics, and phylogeographic patterns in two rodent species-the soft-furred mouse (Praomys jacksoni) and the African wood mouse (Hylomyscus endorobae)-across Kenya's forest landscapes. We found a complex genetic structure, with P. jacksoni exhibiting greater genetic diversity than H. endorobae. The Mt. Kenya P. jacksoni populations are significantly genetically different from those in southwestern forests (Mau Forest, Kakamega Forest, and Loita Hills). In contrast, H. endorobae presented no observable biogeographic structuring across its range. The genetic diversity and geographic structuring patterns highlighted selectively strong effects of forest fragmentation and differing species' ecological and evolutionary responses to these landscape changes. Our findings further underscore the need for expanded sampling across Kenya's highland forests to better understand species' changing diversity and distribution patterns in response to the impacts of human-mediated habitat changes. These insights are critical for informing conservation strategies to preserve biodiversity better in this globally important region.

In Vitro vs. In Vivo Transcriptomic Approach Revealed Core Pathways of Nitrogen Deficiency Response in Tea Plant (Camellia sinensis (L.) Kuntze).

For the first time, we used an in vitro vs. in vivo experimental design to reveal core pathways under nitrogen deficiency (ND) in an evergreen tree crop. These pathways were related to lignin biosynthesis, cell redox homeostasis, the defense response to fungus, the response to Karrikin, amino acid transmembrane transport, the extracellular region, the cellular protein catabolic process, and aspartic-type endopeptidase activity. In addition, the mitogen-activated protein kinase pathway and ATP synthase (ATP)-binding cassette transporters were significantly upregulated under nitrogen deficiency in vitro and in vivo. Most of the MAPK downstream genes were related to calcium signaling (818 genes) rather than hormone signaling (157 genes). Moreover, the hormone signaling pathway predominantly contained auxin- and abscisic acid-related genes, indicating the crucial role of these hormones in ND response. Overall, 45 transcription factors were upregulated in both experiments, 5 WRKYs, 3 NACs, 2 MYBs, 2 ERFs, HD-Zip, RLP12, bHLH25, RADIALIS-like, and others, suggesting their ND regulation is independent from the presence of a root system. Gene network reconstruction displayed that these transcription factors participate in response to fungus/chitin, suggesting that nitrogen response and pathogen response have common regulation. The upregulation of lignin biosynthesis genes, cytochrome genes, and strigalactone response genes was much more pronounced under in vitro ND as compared to in vivo ND. Several cell wall-related genes were closely associated with cytochromes, indicating their important role in flavanols biosynthesis in tea plant. These results clarify the signaling mechanisms and regulation of the response to nitrogen deficiency in evergreen tree crops.

Development of DNA Barcoding for the Rapid Assessment of Biodiversity: 2024 Benjamin Franklin Medal in Earth and Environmental Science presented to Paul D. N. Hebert, Ph.D., FRSC, O.C.

The total number of species on Earth ranges from at least one billion to as many as six billion with the number of animal species likely being between 10 and 150 million and the number of plant species about 340,000. Yet, taxonomists have identified only about 2.2 million species, and naming and identifying new species by traditional methods is a slow process. In 1998, Professor Paul Hebert experienced an epiphany and realized a short length of DNA could be used as a “barcode” for every species. Hebert decided a short sequence from subunit 1 of the mitochondrial gene cytochrome c oxidase (COI) would be the ideal barcode for species identification. He was well aware of the advantage of using a mitochondrial gene, which lacks introns, has low levels of recombination, and has a haploid mode of inheritance. In particular, COI has sufficient sequence variation to distinguish among species, and in the early 1990s, there were good universal primers for COI. In 2003, Hebert and his colleagues published their demonstration of the utility of COI as a barcode in the Proceedings of the Royal Society B: Biological Sciences. Their paper remains the most highly cited paper ever to be published in this journal.Interest in Hebert's vision for barcoding all of life was well-known prior to the publication of the 2003 paper, and the Sloan Foundation in conjunction with Cold Spring Harbor Laboratory sponsored two meetings in 2003 to bring together molecular evolutionary biologists such as Hebert, museum-based systematists, and other researchers to discuss the prospects of using DNA barcoding for rapid identification of species. This led to the establishment of the Consortium for the Barcode of Life (CBOL) in 2004 and then the data platform to support the infrastructure of managing barcode information—BOLD: Barcode of Life Data Systems. As of March 2024, the BOLD platform has almost 16 million barcodes with 255,000 linked to a named animal species and 72,000 linked to a named plant species.The ease of barcoding has led to its use in a variety of ways including environmental monitoring of invasive species, detection of trafficking in exotic and protected species, quality assurance of food, and a broadening of involvement of non-scientists in assessing biodiversity. It is also now possible to extract DNA from environmental DNA (eDNA), and eDNA can be used to detect hard-to-find species. The utility of barcodes will continue to expand because of Hebert's original vision and his ongoing efforts to make barcoding cheap and widely available. The possibilities are only limited by our imagination.

Phylogeography of the Red‐Headed Manakin Supports the River‐Refuge Hypothesis

ABSTRACTAimThe Amazon rainforest is one of the most biodiverse regions on earth, but our understanding of the processes that have shaped its patterns of diversity remains incomplete. One hypothesis for Amazonian speciation is the river‐refuge hypothesis, which suggests that retraction of forests away from the periphery of Amazonia, where rivers are narrow, facilitated divergence of populations separated by wide rivers. Later re‐expansion of forests would have allowed secondary contact between these populations, and co‐occurring hybrid zones may reveal the location where expanding forests first reconnected. Here, we test whether a widespread Amazonian songbird species shows evidence of population contact zones in the eastern headwaters of the Tapajós river, hypothesised to be an area of secondary contact under the river‐refuge hypothesis.LocationAmazon and Atlantic forests of South America.TaxonCeratopipra rubrocapilla (Pipridae, Passeriformes).MethodsWe sampled 147 C. rubrocapilla (Red‐headed Manakin) across its vast range, with 70 samples sequenced using reduced‐representation genomic sequencing and 139 sequenced at the mitochondrial gene cytochrome b. We use population genetic and phylogenetic analyses to investigate patterns of gene flow and population structure across the range, with a particular focus on samples from the headwaters of the Tapajós River to evaluate the potential role of the river‐refuge hypothesis.ResultsWe observe shallow population structure and evidence for widespread gene flow across the range of C. rubrocapilla. Patterns in the Tapajós headwaters match predictions of the river‐refuge hypothesis, with eastern headwater samples most similar to samples farther west on the opposite bank of the Tapajós River.Main ConclusionsThe close co‐occurrence between population contact zones within C. rubrocapilla and other previously studied hybrid zones reinforces the hypothesis that the eastern Tapajós headwaters is where rainforest populations reconnected in the past, following predictions of the river‐refuge hypothesis of Amazonian speciation.

Mitochondrial markers revealed genetic panmixia in the data-deficient yellowfin snapper, Lutjanus xanthopinnis (Actinopterygii: Eupercaria: Lutjanidae), from a hotspot of the southern region of the South China Sea

Understanding the genetic structure and diversity of marine fish is crucial for a sustainable management program. We examined the genetic diversity and historical demographics of the yellowfin snapper, Lutjanus xanthopinnis Iwatsuki, Tanaka et Allen, 2015, in the coastal waters of east Peninsular Malaysia which is bordered by the southern part of the South China Sea using the mitochondrial genes (mtDNA) D-loop and Cytochrome b (Cyt-b). A total of 99 (D-loop) and 78 (Cyt-b) specimens of L. xanthopinnis were successfully sequenced from six locations within the range of species distribution along the Malaysian South China Sea. In the presently reported study, the lack of genetic differentiation among populations can be attributed to historical demographic events, eggs and planktonic larvae’ ability to disperse, spawning patterns, and the absence of physical barriers in the geographical landscape. Maximum likelihood gene trees demonstrated that the populations under study had limited structuring and formed a panmictic population that lacks support for internal clades. The AMOVA (Analysis of Molecular Variance) and population pairwise ФST values indicated high genetic exchange between the study areas. A high level of haplotype diversity (D-loop: 0.948–1.000; Cyt-b: 0.542–0.928), low nucleotide diversity (D-loop: 0.0095–0.0159; Cyt-b: 0.0022–0.0049) and starlike haplotype network indicates a recent expansion of L. xanthopinnis populations in Malaysian South China Sea. However, neutrality and goodness of fit tests revealed non-significant values. Furthermore, the BSP (Bayesian skyline plot) analysis estimated population expansion events during the late Pleistocene. During this epoch, the fluctuation in sea level may have led to an increase in the abundance of resources and favorable habitats for the yellowfin snapper. The presently reported findings could initiate efficient management strategies for L. xanthopinnis along the coastal areas of the Malaysian South China Sea and other nearby nations that share the same waterways.

Tracing the origin of the alien pest Cydia pomonella in Algeria through a worldwide comparison of the species’ DNA barcodes

Abstract DNA barcodes (i.e., gene sequences used as identifiers for species identification) constitute a very useful tool in invasive pest research. Using them, we studied, for the first time, the origin and population structure of the alien Cydia pomonella in Africa, a major apple pest. We sequenced a fragment of the mitochondrial gene Cytochrome c oxidase subunit I (COI) from C. pomonella caterpillars collected in northern Algeria and compared them with DNA barcodes from the rest of the world available at public repositories. The phylogeny built upon that COI database supports the European origin of the species: haplotypes at the base of the phylogeny were registered in this continent. In Algeria, the results suggest that this pest could have been introduced from Europe, with two unique African mutations probably favoured by C. pomonella multivoltinism and large population sizes. Population genetic analyses at three Algerian localities showed neither structure nor founder effects. However, to confirm the underlying process of the observed population patterns, it is necessary to perform analyses using genes with higher mutation rates. Compared to higher resolution markers, mitochondrial DNA barcodes are still a cost‐effective tool for taxonomic determination of unknown specimens and, sometimes, may also allow a preliminary tracing of its origin. This is crucial to detect and stop the spread of invasive pests (i.e., borders). We encourage further studies including functional genes to assess whether any mutations are promoting C. pomonella adaptation to the Northern Africa environment.

Phylogeography of the ambrosia beetle Euwallacea interjectus (Coleoptera: Curculionidae: Scolytinae): an emerging poplar pest and its Fusarium mutualists from poplar plantations in China.

Native to Asia, Euwallacea interjectus (Blandford) (Coleoptera: Curculionidae: Scolytinae) is a destructive and invasive pest of live trees, and now it has been found in the United States and Argentina. In recent years, this pest appeared in high densities in poplar monocultures from Eastern China (Jiangsu and Shanghai) and Argentina and caused significant poplar mortality. However, the origin of the pests related to tree damage and the Fusarium mutualists from some poplar zones in China remained unclear. Here, we provided a broader phylogeographic analysis of E. interjectus based on the mitochondrial gene (cytochrome c oxidase I) to determine the global genetic structure of this species. Five mitochondrial lineages were found in the native area. Populations introduced to the United States were originated from 4 localities. The Argentine population was derived from Japan. The species was observed with strikingly high level of cytochrome c oxidase I intraspecific divergence that exceeded interspecific divergence, but the high intraspecific variation was correlated with geographical locations among the native populations. Two nuclear genes (arginine kinase and carbamoyl-phosphate synthetase 2-aspartate transcarbamylase-dihydroorotase) were more conservative, and intraspecific differences were lower than interspecific differences. The mitochondrial genetic variation was probably caused by evolution of lineages among geographically isolated populations. But it is immature to infer the existence of cryptic species based on cytochrome c oxidase I differences. All samples collected from poplar populations were indigenous and formed close relationship with a specimen from eastern and southern China. Surprisingly, pests from poplar populations in Jiangsu and Shanghai showed different haplotypes and mutualists. This suggested that the control strategies should consider the genetic and mutualistic diversity of beetles at different poplar localities.

Assessment of the Genetic Diversity of the Monogenean Gill Parasite Lamellodiscus echeneis (Monogenea) Infecting Wild and Cage-Reared Populations of Sparus aurata (Teleostei) from the Mediterranean Sea.

The diplectanid monogenean Lamellodiscus echeneis (Wagener, 1857) is a specific and common gill parasite of the gilthead seabream Sparus aurata Linnaeus, 1758, in the Mediterranean Sea. Few isolated molecular studies of this monogenean have been conducted, and its population structure and genetic diversity are poorly understood. This study represents the first analysis of the population genetics of L. echeneis, isolated from wild and cage-reared gilthead seabream from fifteen localities in both the Southern (Tunisia) and Northern (Italy and Spain) regions of the Mediterranean Sea, using nuclear ITS rDNA markers and a partial fragment of the mitochondrial gene cytochrome oxidase subunit I (COI). The phylogenetic trees based on the newly obtained dataset and the previously published sequences of L. echeneis corroborated the spread of only a single species throughout the Mediterranean Sea. The star-like haplotypes network, inferred by COI sequences, suggested a recent population expansion of L. echeneis. This is supported by the observed high haplotype diversity (Hd = 0.918) and low nucleotide diversity (Pi = 0.01595). Population structure-based AMOVA for two groups (the Adriatic Sea and the rest of the Mediterranean Sea) attributed 35.39% of the total variation to differences within populations, 16.63% to differences among populations within groups, and 47.99% to differences among groups. Fixation indices were significant, with a high FST value (0.64612), likely related to the divergence of the parasite populations from the Adriatic Sea and other Mediterranean regions. Phylogenetic analyses grouped all samples into the main clade corresponding to L. echeneis from several localities. This study provides insight into the genetic variation between L. echeneis populations, and did not show a clear genetic structure between populations of L. echeneis throughout Tunisian, Italian, and Spanish localities, which can be attributed to the considerable gene flow between the populations favoured by the potential for host dispersion within the Mediterranean Sea. Finally, haplotypes shared between wild and cage-reared hosts provided evidence for the potential for cross-infection between wild and farmed hosts in the Mediterranean Sea.

Specific interaction of resorufin to outer-membrane cytochrome OmcE of Geobacter sulfurreducens: A new insight on artificial electron mediators in promoting extracellular electron transfer

Bioelectrochemical system (BES) is a unique biotechnology for wastewater treatment and energy recovery, and extracellular electron transfer (EET) between microbe and electrode is the key to optimize the performance of BESs. Resazurin is an effective artificial compound that can promote EET in BESs, but the way how it transports electrons is not fully understood. In this study differential pulse voltammetry revealed that the redox potential of resorufin (RR) (intermediate of resazurin reduction, actual electron mediator) within Geobacter sulfurreducens biofilm was positively shifted by 100 mV than that of free RR, and this shift was attenuated by the mutation of outer-membrane cytochrome gene omcE but not by omcS and omcZ mutation, indicating that RR specifically interacted with OmcE. By using heterologously expressed OmcE monomers in Escherichia coli, it was found that RR bonded with OmcE monomers with a moderate intensity (dissociation constant of 720 nM), and their interaction obviously increased the content of α helix in OmcE monomers. Biomolecular analysis indicated that heme II of OmcE monomer might be the binding site for RR (binding energy of -7.01 kJ/mol), which were favorable for electron transfer within OmcE-RR complex. Comparative transcriptomics showed that RZ addition significantly upregulated the expression of omcE, periplasmic cytochrome gene ppcB, and outer-membrane genes omaB, ombB and omcB, thus, it was hypothesized that OmcE-bound RR might serve as potential electron acceptor of OmbB-OmaB-OmcB porin complex which passes electrons across outer membrane. Our work demonstrated a new pathway of artificial electron mediators in facilitating EET in Geobacter species, which may guide the application of electron mediator in improving the performance of BESs.

Under the Sea: Investigation of Telson Morphology and Cryptic Diversity within Eucopia sculpticauda, a Deep-Sea Lophogastrid from the Gulf of Mexico (Peracarida: Lophogastrida).

The field of phylogenetics employs a variety of methods and techniques to study the evolution of life across the planet. Understanding evolutionary relationships is crucial to enriching our understanding of how genes and organisms have evolved throughout time and how they could possibly evolve in the future. Eucopia sculpticauda Faxon, 1893 is a deep-water peracarid in the order Lophogastrida Boas, 1883, which can often be found in high abundances in pelagic trawls. The species can be found along the Mariana Trench, in the Mid-Atlantic Ridge, west Atlantic and east Pacific Oceans, and in the Gulf of Mexico and as deep as 7526 m. Recent collections of E. sculpticauda in the Gulf of Mexico have revealed putative cryptic diversity within the species based on both molecular and morphological evidence. Previous studies have documented two different morphotypes of the telson: the terminal part of the pleon (abdomen) and part of the tail fan. In adults, the morphotypes can be distinguished by lateral constrictions in the telson. This evidence, combined with a previous barcoding study, led to the speculation that telson morphology may be a distinguishing character useful to define cryptic diversity within E. sculpticauda. This study presents additional molecular data from the mitochondrial genes cytochrome c oxidase subunit I, and the large ribosomal subunit (16S), and the nuclear histone 3 gene (H3) to investigate telson morphotypes in relation to evolutionary history within this species. Molecular data identified two strongly supported clades, lending support for potential cryptic diversification within the Gulf of Mexico. Investigations into telson morphology suggest that this character may be informative, but the morphotypes were sometimes ambiguous and additional characters could not be found that discriminate clades. At present, our data suggest early evidence for cryptic diversification within Gulf of Mexico populations, but additional morphological characters and geographic sampling are needed before a new species can be described.

High Expression of AhR and Environmental Pollution as AhR-Linked Ligands Impact on Oncogenic Signaling Pathways in Western Patients with Gastric Cancer-A Pilot Study.

The vast majority of gastric cancer (GC) cases are adenocarcinomas including intestinal and diffuse GC. The incidence of diffuse GC, often associated with poor overall survival, has constantly increased in Western countries. Epidemiological studies have reported increased mortality from GC after occupational exposure to pro-carcinogens that are metabolically activated by cytochrome P450 enzymes through aryl hydrocarbon receptor (AhR). However, little is known about the role of AhR and environmental AhR ligands in diffuse GC as compared to intestinal GC in Western patients. In a cohort of 29, we demonstrated a significant increase in AhR protein and mRNA expression levels in GCs independently of their subtypes and clinical parameters. AhR and RHOA mRNA expression were correlated in diffuse GC. Further, our study aimed to characterize in GC how AhR and the AhR-related genes cytochrome P450 1A1 (CYP1A1) and P450 1B1 (CYP1B1) affect the mRNA expression of a panel of genes involved in cancer development and progression. In diffuse GC, CYP1A1 expression correlated with genes involved in IGF signaling, epithelial-mesenchymal transition (Vimentin), and migration (MMP2). Using the poorly differentiated KATO III epithelial cell line, two well-known AhR pollutant ligands, namely 2-3-7-8 tetrachlorodibenzo-p-dioxin (TCDD) and benzo[a]pyrene (BaP), strongly increased the expression of CYP1A1 and Interleukin1β (IL1B), and to a lesser extend UGT1, NQO1, and AhR Repressor (AhRR). Moreover, the increased expression of CYP1B1 was seen in diffuse GC, and IHC staining indicated that CYP1B1 is mainly expressed in stromal cells. TCDD treatment increased CYP1B1 expression in KATO III cells, although at lower levels as compared to CYP1A1. In intestinal GC, CYP1B1 expression is inversely correlated with several cancer-related genes such as IDO1, a gene involved in the early steps of tryptophan metabolism that contributes to the endogenous AhR ligand kynurenine expression. Altogether, our data provide evidence for a major role of AhR in GC, as an environmental xenobiotic receptor, through different mechanisms and pathways in diffuse and intestinal GC. Our results support the continued efforts to clarify the identity of exogenous AhR ligands in diffuse GC in order to define new therapeutic strategies.

MORPHOLOGICAL AND MOLECULAR CHARACTERIZATION OF Donax faba (BIVALVIA: DONACIDAE) OBTAINED FROM KUTANG BEACH, LAMONGAN, INDONESIA

ARTICLE HIGLIGHTSThis study revealed 19 morphological variations of edible wedge clams, Donax faba (Bivalvia: Donacidae), from Kutang Beach, Lamongan, Indonesia, which has significant role as part of coastal ecosystem.This reseach also highlights the DNA barcoding of Donax faba based on COI gene (Cytochrome C Oxidase Subunit I).The average genetic distance of the research samples was 0.46%, while the value of this parameter between the research samples and the ingroup was found to be 1.51%. ABSTRACTDonax faba is a type of wedge clams with significant ecological and economic roles, as well as variations in color, pattern, and morphometric properties. Recently, a particular population of unidentified D. faba was reported from Kutang Beach, Lamongan, Indonesia. Therefore, this research aimed to assess the morphological variations and molecular characteristics of D. faba obtained from Kutang Beach based on COI gene. A total of 288 samples were collected during the lowest tide for morphological characterization of the color, pattern, and morphometrics of the shells. Additionally, molecular characterization was conducted based on the composition of nucleotide bases and amino acids of COI gene, genetic distance, as well as the relationships. The results showed that D. faba had 19 morphological variations, among which the most dominant type contained a whitish exterior with brown spots and a whitish purple interior. The average genetic distance of the samples was 0.46%, while the value was calculated as 1.51% between the samples and the ingroup. Automatic Barcode Gap Discovery (ABGD) analysis performed using a prior maximal distance of 0.001 showed the separation of these species into distinct categories.