Zebrafish as Versatile Model for Assessing Animal Venoms and Toxins: Current Applications and Future Prospects.

Animal venoms and toxins hold promise as sources of novel drug candidates, therapeutic agents, and biomolecules. To fully harness their potential, it is crucial to develop reliable testing methods that provide a comprehensive understanding of their effects and mechanisms of action. However, traditional rodent assays encounter difficulties in mimicking venom-induced effects in human due to the impractical venom dosage levels. The search for reliable testing methods has led to the emergence of zebrafish (Danio rerio) as a versatile model organism for evaluating animal venoms and toxins. Zebrafish possess genetic similarities to humans, rapid development, transparency, and amenability to high-throughput assays, making it ideal for assessing the effects of animal venoms and toxins. This review highlights unique attributes of zebrafish and explores their applications in studying venom- and toxin-induced effects from various species, including snakes, jellyfish, cuttlefish, anemones, spiders, and cone snails. Through zebrafish-based research, intricate physiological responses, developmental alterations, and potential therapeutic interventions induced by venoms are revealed. Novel techniques such as CRISPR/Cas9 gene editing, optogenetics, and high-throughput screening hold great promise for advancing venom research. As zebrafish-based insights converge with findings from other models, the comprehensive understanding of venom-induced effects continues to expand, guiding the development of targeted interventions and promoting both scientific knowledge and practical applications.

M2 Macrophage Prominently Distributed in the Rat's Colon of DMH-Induced Inflammation Associated Colorectal Cancer.

OBJECTIVE: The aim of this study is to examine the M1 and M2 macrophages distribution in the rat's colon of DMH-induced inflammation associated colorectal cancer. METHODS: Colon tissue of three groups of 4 rats that induced using 1,2 dimethylhydrazine (DMH) at 30 mg/kg bw every week for 9, 11, and 13 weeks were used. The M1 and M2 distribution was examined by using antibody anti iNOS for M1 and anti-CD163 for M2 with immunohistochemistry method. The data was presents in figure and table in the form of percentage. RESULT: M1 macrophage was found in all groups in the low distribution level (25% - 50%), while M2 macrophage was observed in all groups with 100% distribution. In the longer period of DMH induction, M2 macrophages was distributed more abundant. CONCLUSION: All of the rat's colon showing chronic inflammation that led to the tumorigenesis.

Prediction of the interaction between Calloselasma rhodostoma venom-derived peptides and cancer-associated hub proteins: A computational study.

The use of peptide drugs to treat cancer is gaining popularity because of their efficacy, fewer side effects, and several advantages over other properties. Identifying the peptides that interact with cancer proteins is crucial in drug discovery. Several approaches related to predicting peptide-protein interactions have been conducted. However, problems arise due to the high costs of resources and time and the smaller number of studies. This study predicts peptide-protein interactions using Random Forest, XGBoost, and SAE-DNN. Feature extraction is also performed on proteins and peptides using intrinsic disorder, amino acid sequences, physicochemical properties, position-specific assessment matrices, amino acid composition, and dipeptide composition. Results show that all algorithms perform equally well in predicting interactions between peptides derived from venoms and target proteins associated with cancer. However, XGBoost produces the best results with accuracy, precision, and area under the receiver operating characteristic curve of 0.859, 0.663, and 0.697, respectively. The enrichment analysis revealed that peptides from the Calloselasma rhodostoma venom targeted several proteins (ESR1, GOPC, and BRD4) related to cancer.

Exogenously applied Casuarina equisetifolia leaf extracts act as an osmoprotectant on proline accumulation under drought stress in local rice from Indonesia.

The effects of exogenously supplied osmoprotectants in crops have not yet been extensively studied. In this study, an osmoprotectant containing a high concentration of proline (2.5 g mol-1 FW) was obtained from a Casuarina equisetifolia leaf extract. The effect of the extract was evaluated in local Indonesian rice cultivars Boawae Seratus Malam (BSM), Gogo Jak (GJ), Situ Bagendit (SB) (drought-tolerant), Kisol Manggarai (KM) and Ciherang (drought-susceptible) cultivars under drought at the morphological, physiological, and genetic levels. Under drought, the KM showed an increased level of OsWRKY, OsNAC, OsDREB1A, and OsDREB2A expression after application of the osmoprotectant, leading to the activation of proline synthesis genes including OsP5CS1, OsP5CR, and OsProDH, while the tolerant cultivars (BSM, GJ, and SB) showed no difference. The content of chlorophyll, carotenoids, anthocyanins, ascorbate peroxidase, catalase, and superoxide dismutase activities also increased in GJ and KM, during drought stress and applied osmoprotectants, but remained low in the BSM. We conclude that the foliar application of osmoprotectants derived from C.equisetifolia caused an accumulation of proline in susceptible plants. The existence of these extracts stabilizes leaf cells and supports photosynthetic compartments and carbon assimilation in plants, leading to growth.

Seed Halopriming: A Promising Strategy to Induce Salt Tolerance in Indonesian Pigmented Rice.

Unfavorable environmental conditions and climate change impose stress on plants, causing yield losses worldwide. The Indonesian pigmented rice (Oryza sativa L.) cultivars Cempo Ireng Pendek (black rice) and Merah Kalimantan Selatan (red rice) are becoming popular functional foods due to their high anthocyanin contents and have great potential for widespread cultivation. However, their ability to grow on marginal, high-salinity lands is limited. In this study, we investigated whether seed halopriming enhances salt tolerance in the two pigmented rice cultivars. The non-pigmented cultivars IR64, a salt-stress-sensitive cultivar, and INPARI 35, a salt tolerant, were used as control. We pre-treated seeds with a halopriming solution before germination and then exposed the plants to a salt stress of 150 mM NaCl at 21 days after germination using a hydroponic system in a greenhouse. Halopriming was able to mitigate the negative effects of salinity on plant growth, including suppressing reactive oxygen species accumulation, increasing the membrane stability index (up to two-fold), and maintaining photosynthetic pigment contents. Halopriming had different effects on the accumulation of proline, in different rice varieties: the proline content increased in IR64 and Cempo Ireng Pendek but decreased in INPARI 35 and Merah Kalimantan Selatan. Halopriming also had disparate effects in the expression of stress-related genes: OsMYB91 expression was positively correlated with salt treatment, whereas OsWRKY42 and OsWRKY70 expression was negatively correlated with this treatment. These findings highlighted the potential benefits of halopriming in salt-affected agro-ecosystems.

RWP-RK Domain 3 (OsRKD3) induces somatic embryogenesis in black rice.

BACKGROUND: Plants have the unique capability to form embryos from both gametes and somatic cells, with the latter process known as somatic embryogenesis. Somatic embryogenesis (SE) can be induced by exposing plant tissues to exogenous growth regulators or by the ectopic activation of embryogenic transcription factors. Recent studies have revealed that a discrete group of RWP-RK DOMAIN-CONTAINING PROTEIN (RKD) transcription factors act as key regulators of germ cell differentiation and embryo development in land plants. The ectopic overexpression of reproductive RKDs is associated with increased cellular proliferation and the formation of somatic embryo-like structures that bypass the need for exogenous growth regulators. However, the precise molecular mechanisms implicated in the induction of somatic embryogenesis by RKD transcription factors remains unknown. RESULTS: In silico analyses have identified a rice RWP-RK transcription factor, named Oryza sativa RKD3 (OsRKD3), which is closely related to Arabidopsis thaliana RKD4 (AtRKD4) and Marchantia polymorpha RKD (MpRKD) proteins. Our study demonstrates that the ectopic overexpression of OsRKD3, which is expressed preferentially in reproductive tissues, can trigger the formation of somatic embryos in an Indonesian black rice landrace (Cempo Ireng) that is normally resistant to somatic embryogenesis. By analyzing the transcriptome of induced tissue, we identified 5,991 genes that exhibit differential expression in response to OsRKD3 induction. Among these genes, 50% were up-regulated while the other half were down-regulated. Notably, approximately 37.5% of the up-regulated genes contained a sequence motif in their promoter region, which was also observed in RKD targets from Arabidopsis. Furthermore, OsRKD3 was shown to mediate the transcriptional activation of a discrete gene network, which includes several transcription factors such as APETALA 2-like (AP2-like)/ETHYLENE RESPONSE FACTOR (ERF), MYB and CONSTANS-like (COL), and chromatin remodeling factors associated with hormone signal transduction, stress responses and post-embryonic pathways. CONCLUSIONS: Our data show that OsRKD3 modulates an extensive gene network and its activation is associated with the initiation of a somatic embryonic program that facilitates genetic transformation in black rice. These findings hold substantial promise for improving crop productivity and advancing agricultural practices in black rice.

PEBP Signaling Network in Tubers and Tuberous Root Crops.

Tubers and tuberous root crops are essential carbohydrate sources and staple foods for humans, second only to cereals. The developmental phase transition, including floral initiation and underground storage organ formation, is controlled by complex signaling processes involving the integration of environmental and endogenous cues. FLOWERING LOCUS T (FT) and TERMINAL FLOWER 1/CENTRORADIALIS (TFL1/CEN), members of the phosphatidylethanolamine-binding protein (PEBP) gene family, play a central role in this developmental phase transition process. FT and FT-like proteins have a function to promote developmental phase transition, while TFL1/CEN act oppositely. The balance between FT and TFL1/CEN is critical to ensure a successful plant life cycle. Here, we present a summarized review of the role and signaling network of PEBP in floral initiation and underground storage organ formation, specifically in tubers and tuberous root crops. Lastly, we point out several questions that need to be answered in order to have a more complete understanding of the PEBP signaling network, which is crucial for the agronomical improvement of tubers and tuberous crops.

Bibliometric Analysis of Literature in Snake Venom-Related Research Worldwide (1933-2022).

Snake envenomation is a severe economic and health concern affecting countries worldwide. Snake venom carries a wide variety of small peptides and proteins with various immunological and pharmacological properties. A few key research areas related to snake venom, including its applications in treating cancer and eradicating antibiotic-resistant bacteria, have been gaining significant attention in recent years. The goal of the current study was to analyze the global profile of literature in snake venom research. This study presents a bibliometric review of snake venom-related research documents indexed in the Scopus database between 1933 and 2022. The overall number of documents published on a global scale was 2999, with an average annual production of 34 documents. Brazil produced the highest number of documents (n = 729), followed by the United States (n = 548), Australia (n = 240), and Costa Rica (n = 235). Since 1963, the number of publications has been steadily increasing globally. At a worldwide level, antivenom, proteomics, and transcriptomics are growing hot issues for research in this field. The current research provides a unique overview of snake venom research at global level from 1933 through 2022, and it may be beneficial in guiding future research.

Seed Halopriming Improves Salinity Tolerance of Some Rice Cultivars During Seedling Stage.

BACKGROUND: Saline land in coastal areas has great potential for crop cultivation. Improving salt tolerance in rice is a key to expanding the available area for its growth and thus improving global food security. Seed priming with salt (halopriming) can enhance plant growth and decrease saline intolerance under salt stress conditions during the subsequent seedling stage. However, there is little known about rice defense mechanisms against salinity at seedling stages after seed halopriming treatment. This study focused on the effect of seed halopriming treatment on salinity tolerance in a susceptible cultivar, IR 64, a resistant cultivar, Pokkali, and two pigmented rice cultivars, Merah Kalimantan Selatan (Merah Kalsel) and Cempo Ireng Pendek (CI Pendek). We grew these cultivars in hydroponic culture, with and without halopriming at the seed stage, under either non-salt or salt stress conditions during the seedling stage. RESULTS: The SES scoring assessment showed that the level of salinity tolerance in susceptible cultivar, IR 64, and moderate cultivar, Merah Kalsel, improved after seed halopriming treatment. Furthermore, seed halopriming improved the growth performance of IR 64 and Merah Kalsel rice seedlings. Quantitative PCR revealed that seed halopriming induced expression of the OsNHX1 and OsHKT1 genes in susceptible rice cultivar, IR 64 and Merah Kalsel thereby increasing the level of resistance to salinity. The expression levels of OsSOS1 and OsHKT1 genes in resistant cultivar, Pokkali, also increased but there was no affect on the level of salinity tolerance. On the contrary, seed halopriming decreased the expression level of OsSOS1 genes in pigmented rice cultivar, CI Pendek, but did not affect the level of salinity tolerance. The transporter gene expression induction significantly improved salinity tolerance in salinity-susceptible rice, IR 64, and moderately tolerant rice cultivar, Merah Kalsel. Induction of expression of the OsNHX1 and OsHKT1 genes in susceptible rice, IR 64, after halopriming seed treatment balances the osmotic pressure and prevents the accumulation of toxic concentrations of Na+, resulting in tolerance to salinity stress. CONCLUSION: These results suggest that seed halopriming can improve salinity tolerance of salinity-susceptible and moderately tolerant rice cultivars.

Identification and characterization of drought-tolerant local pigmented rice from Indonesia.

Water is essential to support life. Because limited water availability may affect their life cycles, plants have developed multiple responses to drought stress. Plant physiological and metabolic changes during drought may reflect changes that occur at the level of gene expression. In this study, we investigated the variation in drought-mitigating strategies employed by pigmented rice (Oryza sativa) varieties and the genes involved in their possible drought tolerance. We screened 21 local pigmented rice cultivars from Indonesia for increased drought tolerance using the fraction transpirable soil water method to exert precise control of the drought stress imposed on plants. We then determined the expression of OsDREB1A, OsNAC6, OsNHX1, OsCuZnSOD2, OsOSCAT2, and OsCAT3 in plants grown under well-watered conditions and under moderate or severe drought stress. Among the pigmented rice cultivars, Merah Pari Eja had the greatest drought tolerance, while the red rice Inpari 24 had the highest mortality rate (60%). We also included the white rice cultivar Putih Payo, which is fully sensitive to drought (with 100% mortality under the conditions used) as a negative control. Gene expression profiling revealed a general upregulation of drought-related genes in Merah Pari Eja and a downregulation of such genes in the other two cultivars. Measurements of antioxidant enzyme activity, leaf damage, free radicals, chlorophyll, and anthocyanin contents provided further evidence that Merah Pari Eja is more drought tolerant than the other two cultivars. We conclude that OsDREB1A, OsNAC6, OsNHX1, OsCuZnSOD2, OsOSCAT2 and OsCAT3 expression patterns can reveal plants that have increased drought tolerance.

14-3-3 proteins act as intracellular receptors for rice Hd3a florigen.

'Florigen' was proposed 75 years ago to be synthesized in the leaf and transported to the shoot apex, where it induces flowering. Only recently have genetic and biochemical studies established that florigen is encoded by FLOWERING LOCUS T (FT), a gene that is universally conserved in higher plants. Nonetheless, the exact function of florigen during floral induction remains poorly understood and receptors for florigen have not been identified. Here we show that the rice FT homologue Hd3a interacts with 14-3-3 proteins in the apical cells of shoots, yielding a complex that translocates to the nucleus and binds to the Oryza sativa (Os)FD1 transcription factor, a rice homologue of Arabidopsis thaliana FD. The resultant ternary 'florigen activation complex' (FAC) induces transcription of OsMADS15, a homologue of A. thaliana APETALA1 (AP1), which leads to flowering. We have determined the 2.4 Å crystal structure of rice FAC, which provides a mechanistic basis for florigen function in flowering. Our results indicate that 14-3-3 proteins act as intracellular receptors for florigen in shoot apical cells, and offer new approaches to manipulate flowering in various crops and trees.

The 14-3-3 protein GF14c acts as a negative regulator of flowering in rice by interacting with the florigen Hd3a.

Hd3a and FT proteins have recently been proposed to act as florigens in rice and Arabidopsis, respectively; however, the molecular mechanisms of their function remain to be determined. In this study, we identified GF14c (a 14-3-3 protein) as an Hd3a-interacting protein in a yeast two-hybrid screen. In vitro and in vivo experiments, using a combination of pull-down assays and bimolecular fluorescence complementation, confirmed the interaction between Hd3a and GF14c. Functional analysis using either GF14c overexpression or knockout transgenic rice plants indicated that this interaction plays a role in the regulation of flowering. GF14c-overexpressing plants exhibited a delay in flowering and the knockout mutants displayed early flowering relative to the wild-type plants under short-day conditions. These results suggest that GF14c acts as a negative regulator of flowering by interacting with Hd3a. Since the 14-3-3 protein has been shown to interact with FT protein in tomato and Arabidopsis, our results in rice provide important findings about FT signaling in plants.