Journal of Biosciences最新文献

Whole-brain calcium imaging combined with multicolor cell identification is a revolutionary technique for elucidating structure-function relationships in the neural network of the nematode Caenorhabditis elegans. Existing genetically encoded calcium indicator (GCaMP) (for calcium imaging) + neuronal polychromatic atlas of landmarks for whole-brain imaging (NeuroPAL) (for cell identification) strains, however, exhibit suboptimal behavioral and neural responses to external stimuli, at least under certain conditions. To address this, we established a new strain of GCaMP + NeuroPAL, KDK94, and found that this new strain showed improved behavioral and/or neural responses to the repulsive odor 2-nonanone and electric stimuli compared with existing strains. Whole-brain calcium and NeuroPAL imaging using the new strain with several technical improvements revealed that in addition to the previously known amphid sensory neuron (ASH) and amphid wing 'B' cells (AWB) sensory neurons, the AWC^OFF neuron responds to both stepwise increases in the water phase and subtle gradual increases in the air phase of 2-nonanone concentration. The improvement of the whole-brain imaging system with cell identification and the transgenic strain for the system may provide new insights into the neural circuit dynamics underlying the basic brain functions, such as learning, decisionmaking, and emotion, of C. elegans.

Marine fungi are the leading producers of bioactive metabolites with medicinal properties against several diseases. However, since marine species survive in diverse climates, they are usually difficult to culture in laboratory setups, making them challenging to study. This study aimed to optimize culture conditions for marine fungi and evaluate the inhibitory action of the marine extract on primary pro-inflammatory cytokines. Culture conditions for marine fungi were optimized using biomass production, hyphal density, and radial extension, considering temperature and humidity. The study isolated a new Aspergillus fumigatus variant, AFK11 (GenBank accession no. JX022941), showing 96% similarity to reported strains. Ethyl acetate extracts of AFK11 significantly inhibited primary pro-inflammatory cytokines, tumor necrosis factor-α, and interleukin-6, in a dose-dependent manner. This research highlights the successful laboratory culture and anti-inflammatory potential of the new strain of Aspergillus, AFK11, emphasizing the need for further research for its potential in various other diseases such as cancer.

Flying fishes (Exocoetidae) are a highly specialized group of Beloniformes, with 4 subfamilies, 7 genera, and 78 species. However,only a small number of species of flying fishes have the mitochondrial genome described sof ar. Considering the importance of mitogenomes in evolution, in this study we aimed to expand the description of mitochondrial genomes and the phylogenetic relationships of Exocoetidae. We used publicly available DNA-Seq libraries to assemble the mitochondrial genomes of 7 species of flying fishes. The mitochondrial genomes of Exocoetidae showed conserved features among all species. With 22 tRNAs, 2 rRNAs, and 13 protein-coding genes, they share common features among vertebrates.Cheilopogon was reconstructedaspolyphyletic, with four clades, which reinforces previous studies that recovered Cheilopogon as non-monophyletic.Werecoveredallfour subfamilies as monophyletic,with Parexocoetinae as the sister group of all other subfamilies.The genetic distance between Exocoetidae species was two times smaller than the genetic distance among the Hyporhamphus species, indicating a low genetic divergence in the family. Hereby, this study expanded the knowledge of mitochondrial genome features and presented one of the most comprehensive mitochondrial genome datasets used for studying flying fishestodate. This was achievable using publicly available data, reinforcing the importanceof the re-use of such data in the fields of mitogenomics and phylogenetics.

SCRBQ2 is a croquemort-scavenger receptor class B family protein. The identification of SCRBQ2 in the detergentresistantmembrane of the Anopheles stephensi midgut suggests its role as an ookinete-interacting protein, positioning it as a potential target for transmission-blocking vaccine development. The Asscrbq2 gene was characterized in the Indian urban malaria vector A. stephensi. It was amplified and submitted to GenBankwith accession IDON817188. The gene consists of a coding sequence (CDS) of 2922 bp and encodes a protein of 973 amino acids. The AsSCRBQ2 protein contains two merged CD36 domains, which are conserved across various mosquito species. A similar evolutionary merging of these domains has also been observed in Anopheles culicifacies, Anopheles maculipennis, Anopheles minimus, Anopheles dirus, and Anopheles aquasalis.AsSCRBQ2domain I shows 91.02% similarity with SCRBQ1of Anopheles gambiae,whereas domain II shows 88.68%similarity withSCRBQ2of A. gambiae.The similarity between humanCD36 and AsSCRBQ2 highlights the functional versatility of AsSCRBQ2 in mediating immune responses and facilitating Plasmodium falciparum transmission in malaria vectors. Its dual interactions with PfEMP1 and TLR4 position AsSCRBQ2 as a promising target for transmission-blocking vaccine development and vector control strategies. Codon optimization and in silico cloning showed that the Asscrbq2 gene is highly expressed in the Escherichia coli strain K12. The relative expression pattern shows that the Asscrbq2 gene is highly expressed in the midgut than in the fat body, followed by the salivary glands and ovaries. After blood feeding, upregulation was observed in themidgut at 24 h post bloodmeal (PBM), suggesting a role in blood digestion, and in the fat body at 48 h PBM, indicating a possible role in immunity. Previous studies have suggested a role for SCRBQ2 in Plasmodium invasion of the mosquito midgut; however, this remains to be investigated and validated specifically in A. stephensi.

Neuronal mitochondria are important for neuronal survival and function. Mitochondria buffer calcium, produce ATP, and contribute to reactive oxygen species (ROS) homeostasis, processes that help in neuronal outgrowth and synaptic transmission. Caenorhabditis elegans touch receptor neurons (TRNs) are essential for gentletouch perception and are also used as a model to study axon regeneration. We set up a localized touch habituation assay and investigated the role of the localization of mitochondria along axons and at synapses in the touch circuit for touch habituation behaviour. Mitochondrial transport mutant ric-7 and the metaxin-2;miro- 1 double mutant, which lack mitochondria in axons and at synapses, habituate faster to gentle touch compared with wild-type animals. The faster habituation phenotype is reversed upon restoration of mitochondria along axons and at synapses of only TRNs. Since mitochondria are shown to control actin dynamics, we asked two questions: (i) Can actin dynamics bypass the requirement of axonal mitochondria for touch habituation, and (ii) can upregulation of actin dynamics in injured axons occur independent of axonal mitochondria? Restoring axonal actin dynamics in the absence of axonal mitochondria did not restore defects in gentle-touch habituation of ric-7 animals. Axotomized TRNs in ric-7 animals show upregulation of axonal actin dynamics but do not show filopodial protrusions at the growth cone. Our study suggests that axonal mitochondria play key roles in habituation and axon regeneration independent of dynamic axonal actin.

A significant but relatively neglected structural constituent of tissues and organs is the interstitial space, which pertains to the continuous gaps between cells and around proteins that constitute the extracellular matrix (ECM) (Cenaj et al. 2021). The geometry of the interstitial space, the biochemical composition of the ECM, and the dynamic state of cells, all contribute to the unique characteristics of the tissues and organs of which they are a part. Due largely to the quirks of histological protocols of fixation, the architecture of the interstitial space was less well understood (Benias et al. 2018). A series of influential papers in the past decade has revealed that the interstitial space is laden with characteristic reticular matrix networks that are filled with fluid and mediate communication between cells within and across organs (Cenaj et al. 2021; Pirri et al. 2023).

'Tortured phrases' (TPs) are a linguistic misrepresentation of established jargon or technical terms, and can thus be considered to be factual errors. By synonymizing jargon, TPs reduce the clarity of the scientific message. Given their unique nature, a growing literature on TPs is emerging, a summary of which is provided in this article. Supplementing this growing body of evidence, a curiously unique dataset is presented, namely, of 'sodium hypocrite', which is meant to represent sodium hypochlorite. Examples of TPs in the biological sciences are introduced. Papers that contain 'tortured phrases' should ideally be corrected to accurately represent the correct scientific terms they are currently misrepresenting. This responsibility falls on the shoulders of authors, editors and publishers.

Recent analysis of samples from asteroids Ryugu and Bennu did not reveal any significant amino acid enantiomeric excesses, and these facts appear to contradict the most prevailing view that a slight enantiomeric excess of L-amino acids present on the primitive Earth is the origin of homochirality. From the perspective of continuity in biological evolution, it would again be considered a strong possibility that primordial tRNA aminoacylation could have led to preferential homochiral (L-) protein biosynthesis on the early Earth (Tamura- Schimmel model), and that RNA played a major role in the generation of amino acid homochirality. The results of recent molecular dynamics simulations have also clarified the mechanism of its chiral selectivity.

A meta-analysis of 712 quantitative trait loci (QTLs) associated with traits conferring tolerance to drought, heat, and salinity stress was conducted in chickpea. Of these, 588 QTLs were successfully projected onto a high-density consensus map saturated with 14,246 markers. The resulting meta-QTLs (MQTLs) (54) had an average confidence interval (CI) of 1.01 cM, which was 3.49 times narrower than the CI of the original QTLs (3.53 cM) used in the meta-analysis. Significant single-nucleotide polymorphisms (SNPs) or marker-trait associations identified in previous genome-wide association studies were found to coincide with 36 of these MQTLs. Eleven MQTLs were identified as breeder's MQTLs due to their significant contribution to phenotypic variance (>10%), modest CI (<0.5 cM), and the inclusion of more than 10 QTLs. Candidate gene mining within MQTL regions revealed 49 high-confidence candidate genes associated with various abiotic stresses. Additionally, synteny and ortho-MQTL analyses among chickpea and two other legume crops, pigeon pea and pea, identified 23 ortho-MQTL regions. The markers associated with MQTLs can be utilized for MQTL-assisted breeding and to enhance the prediction accuracy of genomic selection in chickpea.

Tuberculosis (TB), an ancient disease, has plagued humankind for centuries, and the coronavirus disease 2019 (COVID-19) pandemic has worsened the crisis. This article discusses various intersecting aspects of TB and COVID-19, including transmission, co-infection, progression, and resurgence, which underline the necessity of a coordinated response. The respiratory transmission routes shared by both diseases, coupled with overlapping symptoms, complicate their diagnosis. The relationship between COVID-19 and TB is complex, where TB patients could be predisposed to severe COVID-19 due to potential lung damage inflicted by Mycobacterium tuberculosis infection. Also, the disrupted healthcare services and quarantine practices attributed to COVID-19 pandemic could delay treatment and enable the spread of TB, highlighting their complex interplay. The sustenance of TB services amid the pandemic involving improvised diagnosis and access to treatment remains vital. The COVID-19 pandemic has highlighted the importance of coordination between policymakers, healthcare providers, and researchers for developing comprehensive plans for transparent global surveillance systems, treatment regimens, and providing equitable access to healthcare resources, which constitute the key steps for alleviating the dual threat of TB and COVID-19.