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Schistosome helminths infect over 200 million people across 78 countries and are responsible for nearly 300,000 deaths annually. However, our understanding of basic genetic pathways crucial for schistosome development is limited. The sex determining region Y-box 2 (Sox2) protein is a Sox B type transcriptional activator that is expressed prior to blastulation in mammals and is necessary for embryogenesis. Sox expression is associated with pluripotency and stem cells, neuronal differentiation, gut development, and cancer. Schistosomes express a Sox-like gene expressed in the schistosomula after infecting a mammalian host when schistosomes have about 900 cells. Here, we characterized and named this Sox-like gene SmSOXS1. SmSoxS1 protein is a developmentally regulated activator that localizes to the anterior and posterior ends of the schistosomula and binds to Sox-specific DNA elements. In addition to SmSoxS1, we have also identified an additional six Sox genes in schistosomes, two Sox B, one SoxC, and three Sox genes that may establish a flatworm-specific class of Sox genes with planarians. These data identify novel Sox genes in schistosomes to expand the potential functional roles for Sox2 and may provide interesting insights into early multicellular development of flatworms. [ABSTRACT FROM AUTHOR]

In terrestrial hot springs, some members of the microbial mat community utilize sulfur chemical species for reduction and oxidization metabolism. In this study, the diversity and activity of sulfur-metabolizing bacteria were evaluated along a temperature gradient (48–69 °C) in non-acidic phototrophic mats of the Porcelana hot spring (Northern Patagonia, Chile) using complementary meta-omic methodologies and specific amplification of the aprA (APS reductase) and soxB (thiosulfohydrolase) genes. Overall, the key players in sulfur metabolism varied mostly in abundance along the temperature gradient, which is relevant for evaluating the possible implications of microorganisms associated with sulfur cycling under the current global climate change scenario. Our results strongly suggest that sulfate reduction occurs throughout the whole temperature gradient, being supported by different taxa depending on temperature. Assimilative sulfate reduction is the most relevant pathway in terms of taxonomic abundance and activity, whereas the sulfur-oxidizing system (Sox) is likely to be more diverse at low rather than at high temperatures. Members of the phylum Chloroflexota showed higher sulfur cycle-related transcriptional activity at 66 °C, with a potential contribution to sulfate reduction and oxidation to thiosulfate. In contrast, at the lowest temperature (48 °C), Burkholderiales and Acetobacterales (both Pseudomonadota, also known as Proteobacteria) showed a higher contribution to dissimilative sulfate reduction/oxidation as well as to thiosulfate metabolism. Cyanobacteriota and Planctomycetota were especially active in assimilatory sulfate reduction. Analysis of the aprA and soxB genes pointed to members of the order Burkholderiales (Gammaproteobacteria) as the most dominant and active along the temperature gradient for these genes. Changes in the diversity and activity of different sulfur-metabolizing bacteria in photoautotrophic microbial mats along a temperature gradient revealed their important role in hot spring environments, especially the main primary producers (Chloroflexota/Cyanobacteriota) and diazotrophs (Cyanobacteriota), showing that carbon, nitrogen, and sulfur cycles are highly linked in these extreme systems.

Schistosome helminths infect over 200 million people across 78 countries and are responsible for nearly 300,000 deaths annually. However, our understanding of basic genetic pathways crucial for schistosome development is limited. The sex determining region Y-box 2 (Sox2) protein is a Sox B type transcriptional activator that is expressed prior to blastulation in mammals and is necessary for embryogenesis. Sox expression is associated with pluripotency and stem cells, neuronal differentiation, gut development, and cancer. Schistosomes express a Sox-like gene expressed in the schistosomula after infecting a mammalian host when schistosomes have about 900 cells. Here, we characterized and named this Sox-like gene SmSOXS1. SmSoxS1 protein is a developmentally regulated activator that localizes to the anterior and posterior ends of the schistosomula and binds to Sox-specific DNA elements. In addition to SmSoxS1, we have also identified an additional six Sox genes in schistosomes, two Sox B, one SoxC, and three Sox genes that may establish a flatworm-specific class of Sox genes with planarians. These data identify novel Sox genes in schistosomes to expand the potential functional roles for Sox2 and may provide interesting insights into early multicellular development of flatworms.

The arthropod compound eye represents one of two major eye types in the animal kingdom and has served as an essential experimental paradigm for defining fundamental mechanisms underlying sensory organ formation, function, and maintenance. One of the most distinguishing features of the compound eye is the highly regular array of lens facets that define individual eye (ommatidial) units. These lens facets are produced by a deeply conserved quartet of cuticle-secreting cells, called Semper cells (SCs). Also widely known as cone cells, SCs were originally identified for their secretion of the dioptric system, i.e. the corneal lens and underlying crystalline cones. Additionally, SCs are now known to execute a diversity of patterning and glial functions in compound eye development and maintenance. Here, we present an integrated account of our current knowledge of SC multifunctionality in the Drosophila compound eye, highlighting emerging gene regulatory modules that may drive the diverse roles for these cells. Drawing comparisons with other deeply conserved retinal glia in the vertebrate single lens eye, this discussion speaks to glial cell origins and opens new avenues for understanding sensory system support programs. [Display omitted] • Drosophila Semper cells, also known as cone cells, are highly multifunctional. • Semper cells direct the differentiation of all three tissue types in the compound eye. • Semper cells serve homeostatic support roles in the adult compound eye. • Semper cells share many characteristics with vertebrate retinal Muller glia. • Conserved gene regulatory modules are associated with specific Semper cell functions. [ABSTRACT FROM AUTHOR]

Water bodies are frequently polluted, with sulfur oxides being the most common form of water pollution. Therefore, developing a detection mechanism for sulfur oxides in water bodies is particularly urgent. A new fluorescent probe YX-KZBD was designed and developed. This probe releases fluorescent signals with its own sulfurous acid recognition site, detects sulfurous acid based on the Michael addition reaction, and evaluates the pollution degree of sulfur oxides in the water environment through the transformation mode of the sulfur cycle. This probe has high energy transfer efficiency in aqueous solutions. In addition, the fluorescence data obtained by analyzing the water samples were linearly fitted with the gene abundance values of the functional genes of sulfur-producing bacteria, and a significant correlation was obtained. The Kriging interpolation model was used to evaluate the sulfate content distribution at each sampling point to understand the distribution of sulfur oxides in natural water intuitively. The fluorescence signal excited by the probe was also combined with a real-time quantitative polymerase chain reaction (qPCR), and sulfate-reducing and sulfur-oxidizing bacteria were introduced in the sulfur cycle, providing a new method to assess the extent of water pollution effectively. [Display omitted] • This probe associates the WQI-P value with sulfur producing bacteria. • Sulfur producing bacteria combine the sulfur cycle with fluorescence. • The fluorescence detection of the probe has specific selectivity for SO 3 2−. • The probe applies Kriging interpolation technology to water quality assessment. • Small molecule fluorescence probes combine optics with biological Earth models. [ABSTRACT FROM AUTHOR]

Detecting sulfoxide in sediment and water is an essential channel in understanding redox processes and maintaining water quality. Therefore, the creation of quick and efficient sulfoxide detection techniques is crucial to comprehending the ecotoxicity of sulfoxides. However, sulfur oxides were mainly detected in a pure water system, which greatly limited their potential practical applications. Difficulties related to selecting a detection system are a common bottleneck for applications. Herein, a brand-new fluorescent probe called BZ-QL was designed. This probe emits different fluorescence intensities in the sediment and water samples from a natural lake (China's Dianchi Lake). For the first time, the detection of sulfoxide in natural lake was realized on the basis of the correlation of the gene abundance of sulfate-reducing bacteria (SRB) with fluorescence intensities. Results indicated a significant negative correlation between the fluorescence intensities of BZ-QL and the abundance of dsrA for the water samples (R 2 = 0.35, P < 0.01) and sediments (R 2 = 0.16, P < 0.05). The combination of fluorescence intensities and quantitative polymerase chain reaction (qPCR) of SRB could provide unique techniques for detecting sulfur oxides in water samples. Compared with other sulfur dioxide fluorescent probes, the fluorescence detection method in this study introduces the parameter of gene abundance, and applies the probe technology to detect sulfur oxides in natural lakes. In the future, this simple and rapid detection technology could be converted into kits for promotion. In addition, other compounds could be detected by changing the recognition site of the probe. [Display omitted] • BZ-QL could emit different fluorescent signals in the water body and sediments. • Realized the detection of sulfoxide in natural lake based on a unique technology. • A novel tool for the direct detection of sulfur dioxide will be established. • The fluorescence and qPCR will provide a new way for detection of sulfur dioxide. [ABSTRACT FROM AUTHOR]

SoxB transcription factors and histone deacetylases (HDACs) are each major players in the regulation of neurogenesis, but a functional link between them has not been previously demonstrated. Here, we show that SoxB2 and Hdac2 act together to regulate neurogenesis in the cnidarian Hydractinia echinata during tissue homeostasis and head regeneration. We find that misexpression of SoxB genes modifies the number of neural cells in all life stages and interferes with head regeneration. Hdac2 was co-expressed with SoxB2, and its downregulation phenocopied SoxB2 knockdown. We also show that SoxB2 and Hdac2 promote each other’s transcript levels, but Hdac2 counteracts this amplification cycle by deacetylating and destabilizing SoxB2 protein. Finally, we present evidence for conservation of these interactions in human neural progenitors. We hypothesize that crosstalk between SoxB transcription factors and Hdac2 is an ancient feature of metazoan neurogenesis and functions to stabilize the correct levels of these multifunctional proteins.

Nervous systems often consist of a large number of different types of neurons which are generated from neural stem and progenitor cells by a series of symmetric and asymmetric divisions. The origin and early evolution of these neural progenitor systems is not well understood. Here we use a cnidarian model organism, Nematostella vectensis , to gain insight into the generation of neural cell type diversity in a non-bilaterian animal. We identify NvFoxQ2d as a transcription factor that is expressed in a population of spatially restricted, proliferating ectodermal cells that are derived from NvSoxB(2) -expressing neural progenitor cells. Using a transgenic reporter line we show that the NvFoxQ2d cells undergo a terminal, symmetric division to generate a morphologically homogeneous population of putative sensory cells. The abundance of these cells, but not their proliferation status is affected by treatment with the γ-secretase inhibitor DAPT, suggesting regulation by Notch signalling. Our data suggest that intermediate progenitor cells and symmetric divisions contribute to the formation of the seemingly simple nervous system of a sea anemone. [ABSTRACT FROM AUTHOR]

Summary SoxB transcription factors and histone deacetylases (HDACs) are each major players in the regulation of neurogenesis, but a functional link between them has not been previously demonstrated. Here, we show that SoxB2 and Hdac2 act together to regulate neurogenesis in the cnidarian Hydractinia echinata during tissue homeostasis and head regeneration. We find that misexpression of SoxB genes modifies the number of neural cells in all life stages and interferes with head regeneration. Hdac2 was co-expressed with SoxB2 , and its downregulation phenocopied SoxB2 knockdown. We also show that SoxB2 and Hdac2 promote each other’s transcript levels, but Hdac2 counteracts this amplification cycle by deacetylating and destabilizing SoxB2 protein. Finally, we present evidence for conservation of these interactions in human neural progenitors. We hypothesize that crosstalk between SoxB transcription factors and Hdac2 is an ancient feature of metazoan neurogenesis and functions to stabilize the correct levels of these multifunctional proteins. [ABSTRACT FROM AUTHOR]

There is an increasing interest in elemental S as a S fertiliser source, but to be available to plants, elemental S has to be oxidised to sulphate. Elemental S oxidation is known to be affected by soil properties and environmental conditions, but it is still unclear if elemental S oxidation is related to the abundance and diversity of S-oxidising bacteria in cropping soils. In this study, we investigated the abundance and diversity of S-oxidising bacteria by targeting a functional gene ( soxB) and assessed their relationship with elemental S oxidation in ten cropping soils. Positive correlations between soil C, N and S contents on the one hand and the abundances of soxB and 16S ribosomal deoxyribonucleic acid (rRNA) genes on the other suggested that the abundances of S oxidising bacteria in particular and of bacteria in general depend on soil C and nutrient supply. Both soxB and 16S rRNA gene abundances were significantly correlated with the oxidation rate of elemental S ( P < 0.05). In addition, more than 80% of the variation in the oxidation rate of elemental S could be explained by the combination of soxB or 16S rRNA gene abundances and soil pH, suggesting that pH not only affected bacterial abundances but also their activity during elemental S oxidation. Clone libraries constructed with the soxB primers showed genera belonging to Alphaproteobacteria, Betaproteobacteria and Deltaproteobacteria and Actinobacteria. The phylogenetic diversity and relative distribution of soxB clones revealed great differences across soils. However, no direct linkage was found between the diversity of S-oxidising bacteria and elemental S oxidation rate. [ABSTRACT FROM AUTHOR]

In terrestrial hot springs, some members of the microbial mat community utilize sulfur chemical species for reduction and oxidization metabolism. In this study, the diversity and activity of sulfur-metabolizing bacteria were evaluated along a temperature gradient (48-69 °C) in non-acidic phototrophic mats of the Porcelana hot spring (Northern Patagonia, Chile) using complementary meta-omic methodologies and specific amplification of the apr A (APS reductase) and sox B (thiosulfohydrolase) genes. Overall, the key players in sulfur metabolism varied mostly in abundance along the temperature gradient, which is relevant for evaluating the possible implications of microorganisms associated with sulfur cycling under the current global climate change scenario. Our results strongly suggest that sulfate reduction occurs throughout the whole temperature gradient, being supported by different taxa depending on temperature. Assimilative sulfate reduction is the most relevant pathway in terms of taxonomic abundance and activity, whereas the sulfur-oxidizing system (Sox) is likely to be more diverse at low rather than at high temperatures. Members of the phylum Chloroflexota showed higher sulfur cycle-related transcriptional activity at 66 °C, with a potential contribution to sulfate reduction and oxidation to thiosulfate. In contrast, at the lowest temperature (48 °C), Burkholderiales and Acetobacterales (both Pseudomonadota , also known as Proteobacteria ) showed a higher contribution to dissimilative sulfate reduction/oxidation as well as to thiosulfate metabolism. Cyanobacteriota and Planctomycetota were especially active in assimilatory sulfate reduction. Analysis of the apr A and sox B genes pointed to members of the order Burkholderiales ( Gammaproteobacteria ) as the most dominant and active along the temperature gradient for these genes. Changes in the diversity and activity of different sulfur-metabolizing bacteria in photoautotrophic microbial mats along a temperature gradient revealed their important role in hot spring environments, especially the main primary producers ( Chloroflexota / Cyanobacteriota ) and diazotrophs ( Cyanobacteriota ), showing that carbon, nitrogen, and sulfur cycles are highly linked in these extreme systems.

Salt marshes are highly productive ecosystems hosting an intense sulfur (S) cycle, yet little is known about S-oxidizing microorganisms in these ecosystems. Here, we studied the diversity and transcriptional activity of S-oxidizers in salt marsh sediments colonized by the plant Spartina alterniflora, and assessed variations with sediment depth and small-scale compartments within the rhizosphere. We combined next-generation amplicon sequencing of 16S rDNA and rRNA libraries with phylogenetic analyses of marker genes for two S-oxidation pathways (soxB and rdsrAB). Gene and transcript numbers of soxB and rdsrAB phylotypes were quantified simultaneously, using newly designed (RT)-qPCR assays. We identified a diverse assemblage of S-oxidizers, with Chromatiales and Thiotrichales being dominant. The detection of transcripts from S-oxidizers was mostly confined to the upper 5 cm sediments, following the expected distribution of root biomass. A common pool of species dominated by Gammaproteobacteria transcribed S-oxidation genes across roots, rhizosphere, and surrounding sediment compartments, with rdsrAB transcripts prevailing over soxB. However, the root environment fine-tuned the abundance and transcriptional activity of the S-oxidizing community. In particular, the global transcription of soxB was higher on the roots compared to mix and rhizosphere samples. Furthermore, the contribution of Epsilonproteobacteria-related S-oxidizers tended to increase on Spartina roots compared to surrounding sediments. These data shed light on the under-studied oxidative part of the sulfur cycle in salt marsh sediments and indicate small-scale heterogeneities are important factors shaping abundance and potential activity of S-oxidizers in the rhizosphere.

Precise control of self-renewal and differentiation of progenitor cells into the cranial neural crest (CNC) pool ensures proper head development, guided by signaling pathways such as BMPs, FGFs, Shh and Notch. Here, we show that murine Sox2 plays an essential role in controlling progenitor cell behavior during craniofacial development. A "Conditional by Inversion" Sox2 allele (Sox2COIN) has been employed to generate an epiblast ablation of Sox2 function (Sox2EpINV ). Sox2EpINV /+(H) haploinsufficient and conditional (Sox2EpINV /mosaic) mutant embryos proceed beyond gastrulation and die around E11. These mutant embryos exhibit severe anterior malformations, with hydrocephaly and frontonasal truncations, which could be attributed to the deregulation of CNC progenitor cells during their epithelial to mesenchymal transition. This irregularity results in an exacerbated and aberrant migration of Sox10+ NCC in the branchial arches and frontonasal process of the Sox2 mutant embryos. These results suggest a novel role for Sox2 as a regulator of the epithelial to mesenchymal transitions (EMT) that are important for the cell flow in the developing head. [ABSTRACT FROM AUTHOR]

Abstract: Sox genes play important roles in animal developmental processes, including embryogenesis, neural cell stemness, neurogenesis, sex determination, among others. Here, the full length sox gene in planarian Dugesia japonica, named DjsoxB, was cloned using rapid amplification of cDNA ends (RACE). Phylogenetic analysis demonstrates that DjsoxB is highly conserved evolutionarily in metazoans. Whole-mount in situ hybridization found DjsoxB mRNA to be mainly expressed in the head, intestine and mouth in both sexually mature and immature planarians. Moreover, DjsoxB transcripts were detected in the blastema after amputation and throughout the head regeneration processes. The data from real-time PCR showed that the mRNA expression levels of DjsoxB were distinctly up-regulated from 3 to 7days after amputation. These results suggest that DjsoxB gene might be active in CNS formation and functional recovery during head regeneration, maintenance of adult CNS function and the development of other tissues (e.g. intestine) in D. japonica. [Copyright &y& Elsevier]

Sulphur-oxidising bacteria ( SOB) play a key role in the biogeochemical cycling of sulphur in soil ecosystems. However, the ecology of SOB is poorly understood, and there is little knowledge about the taxa capable of sulphur oxidation, their distribution, habitat preferences and ecophysiology. Furthermore, as yet there are no conclusive links between SOB community size or structure and rates of sulphur oxidation. We have developed a molecular approach based on primer design targeting the soxB functional gene of nonfilamentous chemolithotrophic SOB that allows assessment of both abundance and diversity. Cloning and sequencing revealed considerable diversity of known soxB genotypes from agricultural soils and also evidence for previously undescribed taxa. In a microcosm experiment, abundance of soxB genes increased with sulphur oxidation rate in soils amended with elemental sulphur. Addition of elemental sulphur to soil had a significant effect in the soxB gene diversity, with the chemolithotrophic Thiobacillus-like Betaproteobacteria sequences dominating clone libraries 6 days after sulphur application. Using culture-independent methodology, the study provides evidence for links between abundance and diversity of SOB and sulphur oxidation. The methodology provides a new tool for investigation of the ecology and role of SOB in soil sulphur biogeochemistry. [ABSTRACT FROM AUTHOR]

Salt marshes are highly productive ecosystems hosting an intense sulfur (S) cycle, yet little is known about S-oxidizing microorganisms in these ecosystems. Here, we studied the diversity and transcriptional activity of S-oxidizers in salt marsh sediments colonized by the plant Spartina alterniflora, and assessed variations with sediment depth and small-scale compartments within the rhizosphere. We combined next-generation amplicon sequencing of 16S rDNA and rRNA libraries with phylogenetic analyses of marker genes for two S-oxidation pathways (soxB and rdsrAB). Gene and transcript numbers of soxB and rdsrAB phylotypes were quantified simultaneously, using newly designed (RT)-qPCR assays. We identified a diverse assemblage of S-oxidizers, with Chromatiales and Thiotrichales being dominant. The detection of transcripts from S-oxidizers was mostly confined to the upper 5 cm sediments, following the expected distribution of root biomass. A common pool of species dominated by Gammaproteobacteria transcribed S-oxidation genes across roots, rhizosphere, and surrounding sediment compartments, with rdsrAB transcripts prevailing over soxB. However, the root environment fine-tuned the abundance and transcriptional activity of the S-oxidizing community. In particular, the global transcription of soxB was higher on the roots compared to mix and rhizosphere samples. Furthermore, the contribution of Epsilonproteobacteria-related S-oxidizers tended to increase on Spartina roots compared to surrounding sediments. These data shed light on the under-studied oxidative part of the sulfur cycle in salt marsh sediments and indicate small-scale heterogeneities are important factors shaping abundance and potential activity of S-oxidizers in the rhizosphere. [ABSTRACT FROM AUTHOR]

Sulfur-oxidizing bacteria (SOB) play important roles in the sulfur cycle and are widespread in a number of environments, but their occurrence and relationship to geochemical conditions in (hyper)saline lakes are still poorly understood. In this study, the abundance and diversity of SOB populations were investigated in four Qinghai-Tibetan lakes (Erhai Lake, Gahai Lake 1, Gahai Lake 2 and Xiaochaidan Lake) by using quantitative polymerase chain reaction (qPCR) andsoxBgene- (encoding sulfate thiohydrolase) based phylogenectic analyses. qPCR analyses showed that in the studied lakes, the total bacterial 16S rRNA andsoxBgene abundances in the sediments were distinctly higher than in the overlying waters. The 16S rRNA gene abundance in the waters ranged 5.27 × 106–6.09 × 108copies per mL and 7.39 × 1010–2.9 × 1011copies per gram sediment. ThesoxBgene abundance in the waters ranged from 1.88 × 104to 5.21 × 105per mL and 4.73 × 106–2.65 × 107copies per gram sediment. ThesoxBgene in the waters of the two hypersaline lakes (Gahai Lake 2 and Xiaochaidan Lake) was more abundant (2.97 × 105and 5.21 × 105copies per mL) than that in the two low-salinity lakes (1.88 × 104and 3.36 × 104copies per mL). Phylogenetic analysis showed thatAlpha- andBetaproteobacteriawere dominant SOB in the investigated lakes, and the composition of proteobacterial subgroups varied with salinity: in freshwater Erhai Lake and low-salinity Gahai Lake 1, the SOB populations were dominated by theBetaproteobacteria, whereas in hypersaline Lake Gahai 2 and Xiaochaidan Lake, the SOB populations were dominated by Alphaproteobacteria. Overall, salinity played a key role in controlling the diversity and distribution of SOB populations in the investigated Qinghai-Tibetan lakes. [ABSTRACT FROM PUBLISHER]

Abstract: Five acid-tolerant thiosulfate-metabolizing bacteria were isolated from acid mine drainage samples from Garubathan, India. 16S rRNA gene analysis revealed that the strains were affiliated with the genus Burkholderia of the class of Betaproteobacteria. Comparative 16S rRNA gene sequence analyses indicated that the strains designated as GAH1 and GAH2 produced a separate phylogenetic branch having Burkholderia pyrrocinia ATCC 51958T (96–98%) as the closest relative. Strains GAH4 and Burkholderia tropica Ppe8T (93%) branched out separately in the phylogenetic tree. Strain GMX2 was most closely related to Burkholderia cepacia ATCC 25417T (99.6%) and Burkholderia vietnamiensis LMG 10929T (99%). Strain GAH5 was most closely related to B. pyrrocinia ATCC 51958T (98%). Oligotrophy has been demonstrated in all AMD strains of Burkholderia spp. All strains showed chemolithoautotrophic and mixotrophic growth in thiosulfate. Furthermore, cell-free extracts of all test strains possessed thiosulfate and sulfite dehydrogenase activities. Phylogenetic analysis of the soxB gene revealed that GAH4 and GAH2 strains formed a novel cluster, Betaproteobacteria II, having highest similarity with Allochromatium vinosum, a member of Gammaproteobacteria II. [Copyright &y& Elsevier]

Abstract: Twenty-one thiosulfate-oxidizing bacteria were isolated from rhizosphere soils and 16S rRNA analysis revealed that the isolates were affiliated with seven different phylogenetic groups within the Beta and Gamma subclasses of Proteobacteria and Actinobacteria. Among these, five genera, including Dyella, Burkholderia, Alcaligenes, Microbacterium and Leifsonia sp., represented new sulfur oxidizers in rhizosphere soils. The thiosulfate-oxidizing Dyella, Burkholderia, Alcaligenes, Microbacterium, Leifsonia and Pandoraea were able to grow chemolithotrophically with a medium containing thiosulfate and exhibited growth coupled with thiosulfate oxidation. They accumulated intermediate products such as sulfur, sulfite and trithionate in the spent medium during the time course of thiosulfate oxidation, and these products were finally oxidized into sulfate. Furthermore, they possessed thiosulfate-metabolizing enzymes such as rhodanese, thiosulfate oxidase, sulfite oxidase and trithionate hydrolase, suggesting that these bacteria use the ‘S4 intermediate’ (S4I) pathway for thiosulfate oxidation. Phylogenetic analysis of the soxB gene revealed that Pandoraea sp. and Pandoraea pnomenusa strains formed a separate lineage within Betaproteobacteria. [Copyright &y& Elsevier]

Nervous system development has been intensely studied in insects (especially Drosophila melanogaster), providing detailed insights into the genetic regulatory network governing the formation and maintenance of the neural stem cells (neuroblasts) and the differentiation of their progeny. Despite notable advances over the last two decades, neurogenesis in other arthropod groups remains by comparison less well understood, hampering finer resolution of evolutionary cell type transformations and changes in the genetic regulatory network in some branches of the arthropod tree of life. Although the neurogenic cellular machinery in malacostracan crustaceans is well described morphologically, its genetic molecular characterization is pending. To address this, we established an in situ hybridization protocol for the crayfish Procambarus virginalis and studied embryonic expression patterns of a suite of key genes, encompassing three SoxB group transcription factors, two achaete-scute homologs, a Snail family member, the differentiation determinants Prospero and Brain tumor, and the neuron marker Elav. We document cell type expression patterns with notable similarities to insects and branchiopod crustaceans, lending further support to the homology of hexapod-crustacean neuroblasts and their cell lineages. Remarkably, in the crayfish head region, cell emigration from the neuroectoderm coupled with gene expression data points to a neuroblast-independent initial phase of brain neurogenesis. Further, SoxB group expression patterns suggest an involvement of Dichaete in segmentation, in concordance with insects. Our target gene set is a promising starting point for further embryonic studies, as well as for the molecular genetic characterization of subregions and cell types in the neurogenic systems in the adult crayfish brain., (© 2021 The Authors. Developmental Neurobiology published by Wiley Periodicals LLC.)

In the developing Drosophila central nervous system (CNS), neural progenitor (neuroblast [NB]) selection is gated by lateral inhibition, controlled by Notch signaling and proneural genes. However, proneural mutants still generate many NBs, indicating the existence of additional proneural genes. Moreover, recent studies reveal involvement of key epithelial-mesenchymal transition (EMT) genes in NB selection, but the regulatory interplay between Notch signaling and the EMT machinery is unclear. We find that SoxNeuro (SoxB family) and worniu (Snail family) are integrated with the Notch pathway, and constitute the missing proneural genes. Notch signaling, the proneural, SoxNeuro , and worniu genes regulate key EMT genes to orchestrate the NB selection process. Hence, we uncover an expanded lateral inhibition network for NB selection and demonstrate its link to key players in the EMT machinery. The evolutionary conservation of the genes involved suggests that the Notch-SoxB-Snail-EMT network may control neural progenitor selection in many other systems. • Drosophila neuroblast selection is an EMT-like process, gated by the Notch pathway • SoxB and Snail family members constitute missing proneural genes • The Notch and EMT pathways intersect via the EMT gene crumbs • The Notch-SoxB-Snail-EMT pathway orchestrates neuroblast selection and delamination Drosophila neuroblast selection is an epithelial-mesenchymal transition (EMT)-like process, gated by the Notch pathway. However, the interplay between the Notch and EMT pathways was unclear. Arefin et al. characterize an expanded Notch pathway, involving SoxB and Snail genes acting as proneural genes, that intersects with EMT, via crumbs , to orchestrate neuroblast selection. [ABSTRACT FROM AUTHOR]

In this study, we surveyed the abundance and diversity of three sulfur oxidation genes ( sqr , soxB, and dsrA ) using quantitative assays and Miseq high-throughput sequencing. The quantitative assays revealed that soxB is more abundant than sqr and dsrA and is the main contributor to sulfur oxidation. In the diversity analysis, the SOB community mainly comprised the classes Nitrospira , Alphaproteobacteria , Betaproteobacteria , and Gammaproteobacteria . The genera Gallionella , Hydrogenophaga , Limnohabitans , Methylomonas , Nitrospira , Rhodoferax, and Sulfuritalea were abundant in the communities for sqr ; Dechloromonas , Limnohabitans , Paracoccus , Sulfuritalea , Sulfitobacter, and Thiobacillus were abundant in communities for soxB ; Sulfuritalea , Sulfurisoma , and Thiobacillus were abundant in communities for dsrA . This study presented a high diversity of SOB species and functional sulfur-oxidizing genes in Pearl River via high-throughput sequencing, suggesting that the aquatic ecosystem has great potential to scavenge the sulfur pollutants by itself., Competing Interests: Compliance with ethical standardsThe authors declare that they have no conflict of interest in the publication.

The development of a nervous system is a key innovation in the evolution of metazoans, which is illustrated by the presence of a common developmental toolkit for the formation of this organ system. Neurogenesis in the Spiralia, in particular the Platyhelminthes, is, however, poorly understood when compared with other animal groups. Here, we characterize embryonic neurogenesis in the freshwater flatworm Schmidtea polychroa and analyze the expression of soxB and a set of proneural bHLH genes, which are gene families with a well-established role in metazoan early neural development. We show that the nervous system is fully de novo assembled after the early embryo ingests the maternal nutrients. At early stages of neurogenesis, soxB1 genes are expressed in putative neural progenitor cells, whereas soxB2 and neural bHLH genes (achaete-scute, neuroD and beta3) are associated with late neurogenesis and the specification of neural subpopulations of the central and peripheral nervous system. Our findings are consistent with the role of proneural genes in other bilaterians, suggesting that the ancestral neural-specific gene regulatory network is conserved in triclads, despite exhibiting a divergent mode of development., (Copyright © 2014 Elsevier Inc. All rights reserved.)