Loss Of Pigmentation Research Articles

Development of a Multi-Target Strategy for the Treatment of Vitiligo via Machine Learning and Network Analysis Methods.

Vitiligo is a complex disorder characterized by the loss of pigment in the skin. The current therapeutic strategies are limited. The identification of novel drug targets and candidates is highly challenging for vitiligo. Here we proposed a systematic framework to discover potential therapeutic targets, and further explore the underlying mechanism of kaempferide, one of major ingredients from Vernonia anthelmintica (L.) willd, for vitiligo. By collecting transcriptome and protein-protein interactome data, the combination of random forest (RF) and greedy articulation points removal (GAPR) methods was used to discover potential therapeutic targets for vitiligo. The results showed that the RF model performed well with AUC (area under the receiver operating characteristic curve) = 0.926, and led to prioritization of 722 important transcriptomic features. Then, network analysis revealed that 44 articulation proteins in vitiligo network were considered as potential therapeutic targets by the GAPR method. Finally, through integrating the above results and proteomic profiling of kaempferide, the multi-target strategy for vitiligo was dissected, including 1) the suppression of the p38 MAPK signaling pathway by inhibiting CDK1 and PBK, and 2) the modulation of cellular redox homeostasis, especially the TXN and GSH antioxidant systems, for the purpose of melanogenesis. Meanwhile, this strategy may offer a novel perspective to discover drug candidates for vitiligo. Thus, the framework would be a useful tool to discover potential therapeutic strategies and drug candidates for complex diseases.

Physiological and biochemical responses of seedlings of six contrasting barley (Hordeum vulgare L.) cultivars grown under salt-stressed conditions

Salinity stress affects plant growth and development and underlying metabolisms. To mitigate the effects of the stress, plants responded by changing their physiological and biochemical activities and withstand the stress. The present study aimed to determine barley's (Hordeum vulgare L.) physiological and biochemical response to salinity stress conditions for 7 days and 14 days. Six barley cultivars (Alfa93, DWRB73, DL88, NB1, NB3, NDB1173) were grown under controlled conditions, and different level of salinity stress was applied. In addition, seedling growth, physiological and biochemical parameters, plant leaves RWC, and electrolyte leakage were analyzed. The overall seedling growth, RWC, and electrolyte leakage in salt susceptible lines Alfa93 and DWRB73 were low than the salt-tolerant barley lines (DL88, NB1, NB3, and NDB1173). Electrolyte leakage was 26.0 and 20.6% in Alfa93 and DWRB73, whereas it was 17.6, 14.6, 15.3, and 10.4% in DL88, NB1, NB3, and NDB1173, respectively at 300 mM salinity stress. The loss of photosynthetic pigments under salt stress was high in susceptible lines, salinity treated (300 mM NaCl) Alfa93 plants exhibit 49.5% and 59.5% of Chl-a than control plants after 7 and 14 days of treatment, respectively. However, at 300 mM stress level, NB1 (ST) showed less Chl-a loss after 7 days, whereas NDB1173 showed less reduction in Chl-a after 14 days. Antioxidant enzymes such as SOD, POX, CAT, and APX activities in susceptible line Alfa93 and DWRB73 were lower than tolerant lines. PCA analysis demonstrated a positive correlation between antioxidant enzyme activities and genotypes under salinity stress. PCA analysis described DL88 as the most tolerant, and DWRB73 was the most salt susceptible genotype among the studied barley genotypes. The present findings suggest that barley cultivars' physiological and biochemical activities under salinity stress conditions may be used to screen salt-tolerant crops.

Fruit Colour and Novel Mechanisms of Genetic Regulation of Pigment Production in Tomato Fruits

Fruit colour represents a genetic trait with ecological and nutritional value. Plants mainly use colour to attract animals and favour seed dispersion. Thus, in many species, fruit colour coevolved with frugivories and their preferences. Environmental factors, however, represented other adaptive forces and further diversification was driven by domestication. All these factors cooperated in the evolution of tomato fruit, one of the most important in human nutrition. Tomato phylogenetic history showed two main steps in colour evolution: the change from green-chlorophyll to red-carotenoid pericarp, and the loss of the anthocyanic pigmentation. These events likely occurred with the onset of domestication. Then spontaneous mutations repeatedly occurred in carotenoid and phenylpropanoid pathways, leading to colour variants which often were propagated. Introgression breeding further enriched the panel of pigmentation patterns. In recent decades, the genetic determinants underneath tomato colours were identified. Novel evidence indicates that key regulatory and biosynthetic genes undergo mechanisms of gene expression regulation that are much more complex than what was imagined before: post-transcriptional mechanisms, with RNA splicing among the most common, indeed play crucial roles to fine-tune the expression of this trait in fruits and offer new substrate for the rise of genetic variables, thus providing further evolutionary flexibility to the character.

Elusive partners: a review of the auxiliary proteins guiding metabolic flux in flavonoid biosynthesis.

Flavonoids are specialized metabolites widely distributed across the plant kingdom. They are involved in the growth and survival of plants, conferring the ability to filter ultra-violet rays, conduct symbiotic partnerships, and respond to stress. While many branches of flavonoid biosynthesis have been resolved, recent discoveries suggest missing auxiliary components. These overlooked elements can guide metabolic flux, enhance production, mediate stereoselectivity, transport intermediates, and exert regulatory functions. This review describes several families of auxiliary proteins from across the plant kingdom, including examples from specialized metabolism. In flavonoid biosynthesis, we discuss the example of chalcone isomerase-like (CHIL) proteins and their non-catalytic role. CHILs mediate the cyclization of tetraketides, forming the chalcone scaffold by interacting with chalcone synthase (CHS). Loss of CHIL activity leads to derailment of the CHS-catalyzed reaction and a loss of pigmentation in fruits and flowers. Similarly, members of the pathogenesis-related 10 (PR10) protein family have been found to differentially bind flavonoid intermediates, guiding the composition of anthocyanins. This role comes within a larger body of PR10 involvement in specialized metabolism, from outright catalysis (e.g., (S)-norcoclaurine synthesis) to controlling stereochemistry (e.g., enhancing cis-trans cyclization in catnip). Both CHILs and PR10s hail from larger families of ligand-binding proteins with a spectrum of activity, complicating the characterization of their enigmatic roles. Strategies for the discovery of auxiliary proteins are discussed, as well as mechanistic models for their function. Targeting such unanticipated components will be crucial in manipulating plants or engineering microbial systems for natural product synthesis.

Zebrafish as a new model for rhododendrol-induced leukoderma.

Idiopathic leukoderma is a skin disorder characterized by patchy loss of skin pigmentation due to melanocyte dysfunction or deficiency. Rhododendrol (RD) was approved as a cosmetic ingredient in Japan in 2008. However, it was shown to induce leukoderma in approximately 20,000 customers. The prediction of cytotoxicity, especially to melanocytes in vivo, is required to avoid such adverse effects. Since the use of higher vertebrates is prohibited for medicinal and toxicological assays, we used zebrafish, whose melanocytes were regulated by mechanisms similar to mammals. Zebrafish larvae were treated with RD in breeding water for 3days, which caused body lightening accompanied by a decrease in the number of melanophores. Interestingly, black particles were found at the bottom of culture dishes, suggesting that the melanophores peeled off from the body. In addition, RT-PCR analysis suggested that the mRNA levels of melanophore-specific genes were significantly low. An increase in the production of reactive oxygen species was found in larvae treated with RD. The treatments of the fish with other phenol compounds, which have been reported to cause leukoderma, also induced depigmentation and melanophore loss. These results suggest that zebrafish larvae could be used for the evaluation of leukoderma caused by chemicals, including RD.

Antioxidant and anti-aging carbon quantum dots using tannic acid

Overexpression of collagenase, elastase, and tyrosinase is caused by external factors such as ultraviolet (UV) radiation and stress, resulting in wrinkle formation and freckles through the loss of skin elasticity and skin pigmentation. In this study, we developed novel carbon quantum dots (CQDs) with antioxidant and anti-aging properties using tannic acid as a carbon source through a simple microwave-assisted pyrolysis method. The synthesized tannic acid-derived CQDs (T-CQDs) showed bright blue fluorescence (QY = 28.2 ± 4.0%), exhibiting maximum emission at 430 nm under 350 nm excitation. Even though small amount of the T-CQDs (3 μg ml−1) was used, they exhibited excellent free radical scavenging ability (82.8 ± 4.3%). Also, the T-CQDs (10 μg ml−1) revealed remarkable inhibitory activity against skin aging-related collagenase (77.6 ± 4.8%), elastase (52.6 ± 1.0%), and tyrosinase (44.2 ± 1.3%), demonstrating their antioxidant and anti-aging effects. Furthermore, their antioxidant and anti-aging properties were superior to those of tannic acid, L-ascorbic acid, and quercetin used as positive controls. Finally, the T-CQDs effectively suppressed UV-induced reactive oxygen species generation by 30% at the cellular levels and showed high cell viability (99.7 ± 0.8%) even at 500 μg ml−1. These results demonstrate that the T-CQDs with superior antioxidant, anti-aging properties, and low cytotoxicity can be utilized as novel anti-aging materials in cosmetic and nanomedicine fields.

Pleiotropic function of the oca2 gene underlies the evolution of sleep loss and albinism in cavefish

Adaptation to novel environments often involves the evolution of multiple morphological, physiological, and behavioral traits. One striking example of multi-trait evolution is the suite of traits that has evolved repeatedly in cave animals, including regression of eyes, loss of pigmentation, and enhancement of non-visual sensory systems.1,2 The Mexican tetra, Astyanax mexicanus, consists of fish that inhabit at least 30 caves in Mexico and ancestral-like surface fish that inhabit the rivers of Mexico and southern Texas.3 Cave A.mexicanus are interfertile with surface fish and have evolved a number of traits, including reduced pigmentation, eye loss, and alterations to behavior.4-6 To define relationships between different cave-evolved traits, we phenotyped 208 surface-cave F2 hybrid fish for numerous morphological and behavioral traits. We found differences in sleep between pigmented and albino hybrid fish, raising the possibility that these traits share a genetic basis. In cavefish and other species, mutations in oculocutaneous albinism 2 (oca2) cause albinism.7-12 Surface fish with mutations in oca2 displayed both albinism and reduced sleep. Further, this mutation in oca2 fails to complement sleep loss when surface fish harboring this engineered mutation are crossed to independently evolved populations of albino cavefish with naturally occurring mutations in oca2. Analysis of the oca2 locus in wild-caught cave and surface fish suggests that oca2 is under positive selection in 3 cave populations. Taken together, these findings identify oca2 as a novel regulator of sleep and suggest that a pleiotropic function of oca2 underlies the adaptive evolution of albinism and sleep loss.

Widespread cis- and trans-regulatory evolution underlies the origin, diversification, and loss of a sexually dimorphic fruit fly pigmentation trait.

Changes in gene expression are a prominent feature of morphological evolution. These changes occur to hierarchical gene regulatory networks (GRNs) of transcription factor genes that regulate the expression of trait-building differentiation genes. While changes in the expression of differentiation genes are essential to phenotypic evolution, they can be caused by mutations within cis-regulatory elements (CREs) that drive their expression (cis-evolution) or within genes for CRE-interacting transcription factors (trans-evolution). Locating these mutations remains a challenge, especially when experiments are limited to one species that possesses the ancestral or derived phenotype. We investigated CREs that control the expression of the differentiation genes tan and yellow, the expression of which evolved during the gain, modification, and loss of dimorphic pigmentation among Sophophora fruit flies. We show these CREs to be necessary components of a pigmentation GRN, as deletion from Drosophila melanogaster (derived dimorphic phenotype) resulted in lost expression and lost male-specific pigmentation. We evaluated the ability of orthologous CRE sequences to drive reporter gene expression in species with modified (Drosophila auraria), secondarily lost (Drosophila ananassae), and ancestrally absent (Drosophila willistoni) pigmentation. We show that the transgene host frequently determines CRE activity, implicating trans-evolution as a significant factor for this trait's diversity. We validated the gain of dimorphic Bab transcription factor expression as a trans-change contributing to the dimorphic trait. Our findings suggest an amenability to change for the landscape of trans-regulators and begs for an explanation as to why this is so common compared to the evolution of differentiation gene CREs.

Vitiligo – Study In view of familial occurence

Vitiligo – Study In view of familial occurence

Ability of Yeast Metabolic Activity to Reduce Sugars and Stabilize Betalains in Red Beet Juice

To lower the risk of obesity, diabetes, and other related diseases, the WHO recommends that consumers reduce their consumption of sugars. Here, we propose a microbiological method to reduce the sugar content in red beet juice, while incurring only slight losses in the betalain content and maintaining the correct proportion of the other beet juice components. Several yeast strains with different metabolic activities were investigated for their ability to reduce the sugar content in red beet juice, which resulted in a decrease in the extract level corresponding to sugar content from 49.7% to 58.2%. This strategy was found to have the additional advantage of increasing the chemical and microbial stability of the red beet juice. Only slight losses of betalain pigments were noted, to final concentrations of 5.11% w/v and 2.56% w/v for the red and yellow fractions, respectively.

Familial Drusen, Doyne Honeycomb Retinal Dystrophy (Malattia Leventinese), Pigmented Paravenous Chorioretinal Atrophy and Late-Onset Retinal Degeneration

Inherited retinal diseases are a group of rare, heterogeneous eye disorders caused by gene mutations that result in degeneration of the retina. Malattia Leventinese, also known as familial drusen, dominant drusen, or Doyne honeycomb retinal dystrophy, was first described in patients living in the Levantine Valley in canton Ticino of southern Switzerland in 1925. Characteristic clinical findings include radial macular drusen, large confluent drusen, and juxtapapillary drusen. Especially early visual symptoms typically starting in the 3rd and 5th decades include reduced central vision, photophobia, and metamorphopsia. Pigmented paravenous retinochoroidal atrophy (PPRCA) is an uncommon disease characterized by perivenous aggregations of pigment clumps associated with peripapillary and radial zones of retinochoroidal atrophy that are distributed along the retinal veins. Patients are usually asymptomatic and the disease process is non-progressive or slow and subtly progressive. It is commonly bilateral and symmetric. The autosomal- dominant late-onset retinal degeneration (L-ORD), caused by C1QTNF5 gene mutations, shows typical retinal abnormalities that can extend beyond the macula, and patients can report night blindness in addition to central vision loss. Interestingly, L-ORD patients can have long anteriorly inserted lens zonules and loss of iris pigment.

Dual inoculations of arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria boost drought resistance and essential oil yield of common myrtle

Arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) are increasingly being used to enhance crop abiotic stress resistance. Common myrtle is an economically important essential oil-producing plant but knowledge about its drought resistance mechanisms and the drought mitigation potential of AMF and PGPR is scant. Here, we investigated the effects of single and dual AMF (Funneliformis mosseae, Rhizophagus irregularis) and PGPR (Pseudomonas fluorescens, P. putida) inoculation on seedling survival, growth, physiology, and biochemical traits under soil water deficit (100%, 60%, and 30% of field capacity). Under severe drought, all inoculations increased survival compared to non-inoculated seedlings. Drought-related growth impairment was more strongly compensated belowground than aboveground, especially in dual-inoculated plants, indicating prioritized resource allocation to roots probably linked to AMF- and PGPR-induced phytohormone changes. Particularly dual inoculation significantly improved leaf physiology, reduced electrolyte leakage, malondialdehyde, and proline concentrations and mitigated oxidative pigment losses under drought through upregulation of the antioxidant defense as evidenced by (non-)enzymatic antioxidant accumulation, including essential oils. Our findings indicate similarly significant AMF- and PGPR-mediated boosts in myrtle drought resistance through enhanced water and nutrient supply and stimulation of the antioxidant defense. Dual inoculations proved most effective and provide a low-cost approach to optimizing myrtle cultivation and restoration programs.

Macrophage Migration Inhibitory Factor in Vitiligo: Pathogenesis and Potential Therapeutic Aspects

Vitiligo is an acquired skin disorder that is characterized by a gradual loss of skin pigmentation when melanocytes, the skin's pigment-producing cellsis lost. Pathogenicmechanisms are not well understood. Genetic, abnormal biochemical pathways, autoimmune, melanocyte adhesion deficits and nervous system imbalances are among the pathogenic triggers. Vitiligo lesions have also been shown to have macrophage infiltration.Macrophagemigration inhibitory factor (MIF) is a lymphokine that concentrates macrophages at inflammatory sites and is involved in cell-mediated immunity.MIF enhances chemotaxis and macrophage infiltration and upregulates inflammatory responses by inducing the expression of proinflammatory mediators such as TNF-α, nitric oxide and prostaglandin E2.Therapyfor vitiligo includes corticosteroids, immunomodulatory agents, vitamin D nalogues, antioxidants, phototherapy, laser and surgical therapy.However, no single treatment for vitiligo produces consistently good results and treatment response is variable. Narrow-band ultraviolet (NB-UVB, 311–313nm) phototherapy is viewed as backbone of treatment. Systemic therapies such as systemic corticosteroids and methotrexate were previously used to treat vitiligo which was assumed to be auto-immune nature.Pathogenic mechanisms, role of MIF and various treatment guidelines are discussed in this review

Anti-Aging Effectiveness of Avocado Peel Extract Ointment (Persea americana Mill.) against Hydration, Collagen, and Elasticity Levels in Wistar Rat

The skin is a complex organ that protects the body from the external environment. The skin has a variety of functions such as providing a physical permeability barrier, protection from infectious agents, thermoregulation, sensation, protection against ultraviolet (UV) rays, regeneration, and wound healing. Clinically, aging skin is characterized by loss of hydration, rough texture, irregular pigmentation, yellowish discoloration, telangiectasia, deep wrinkles or wrinkles, thinning of the skin, and fine lines. One of the plants that can be used as natural ingredients that are rich in antioxidants and interesting to study is avocado (Persea americana Mill.) from the Lauraceae family, which is a plant that has medicinal properties and contains a variety of nutrients. Besides being consumed as food, avocados are also used as a mixture of cosmetic products. This study aims to assess the anti-aging effectiveness of avocado peel extract on increasing collagen levels, elasticity, and hydration in male rats. A total of 25 rats were divided into 5 groups, each group consisting of 5 white rats; control group (ointment base), avocado peel extract ointment group 2.5%, 5%, 7.5%, and 10%. The entire group of rats will be measured the condition before treatment with the Skin Analyzer EH 900 U including levels of collagen, elasticity, and hydration. After measuring the initial skin condition, the treatment was started by applying ointment until it was evenly distributed over the marked area, the ointment was applied according to the groups that have been set above, the application was carried out 2 times a day for 4 weeks. Changes in skin condition were measured weekly for 4 weeks using the EH 900 U skin analyzer. The results of this study indicate that the methanol extract of avocado peel contains phytochemicals in the form of alkaloids, tannins, phenols, flavonoids, and glycosides. Then the phenolic, flavonoid, and tannin content of the avocado peel methanol extract was 59.55 GAE mg/gram extract, 2.96 QE mg/gram extract, and 22.63 TAE mg/gram extract. After 4 weeks of treatment, there was a significant change in the level of hydration, collagen, and skin elasticity (p<0.05) in all treatment groups, this can be seen from the P-value <0.05, with the group of rats receiving the highest concentration of ointment (10%) showed the highest average, namely hydration 49.60%, collagen 40.20%, and elasticity 68.20%. Changes in hydration levels, collagen, and skin elasticity before and after treatment also showed significant changes (P-value < 0.05) with the highest changes found at a concentration of 10%, namely hydration 88.40%, collagen 60.0%, and elasticity 68.20%. In conclusion, the results of this study showed that administration of avocado peel extract ointment could increase hydration, collagen, and skin elasticity levels compared to controls groups, positively correlated with the increase of the duration and the quantity of avocado peel extract ointment were given. The best formulation that gives the most significant effect is 10% avocado peel extract ointment by increasing levels of hydration, collagen, and elasticity the most significantly.

HCV poly U/UC sequence-induced inflammation leads to metabolic disorders in vulvar lichen sclerosis.

Vulvar lichen sclerosis (VLS) is a dermatologic disorder that affects women worldwide. Women with VLS have white, atrophic papules on the vulva. They suffer from life-long intense pruritus. Corticosteroids are the first-line of treatments and the most effective medicines for VLS. Although VLS has been speculated as an autoimmune disease for a long time, its pathogenesis and the molecular mechanism is largely unknown. We performed a comprehensive multi-omics analysis of paired samples from VLS patients as well as healthy donors. From the RNA-seq analysis, we found that VLS is correlated to abnormal antivirus response because of the presence of Hepatitis C Virus poly U/UC sequences. Lipidomic and metabolomic analysis revealed that inflammation-induced metabolic disorders of fatty acids and glutathione were likely the reasons for pruritus, atrophy, and pigment loss in the vulva. Thus, the present study provides an initial interpretation of the pathogenesis and molecular mechanism of VLS and suggests that metabolic disorders that affect the vulva may serve as therapeutic targets for VLS.

Natural coloring red beetroot under effects of gamma radiation

As color is an important attribute related to the visual appeal and quality of food products, the reduction of pigment losses during food processing is a basic concern for the industry. Based on this, the objective of this work was to evaluate the resistance of betalain from beet against the use of gamma radiation. Analyzes were carried out on pigments belonging to the betalain class on beets exposed to different doses of gamma radiation (Co60) using doses of 5, 10 and 15 kGy on beets, in addition to anon-irradiated sample for control. Color parameters were evaluated using the CIE L, a*, b * methodology, as well as the quantification of betalain in the samples. By of results the color parameters were affected in until 50% in relation the control. And the quantity betalain activity in the sample irradiated with doses of gamma radiation was more less 65% in relation the control. Therefore, it can be concluded that there is a potential resistance of the betalain pigment in the face of high doses of radiation, which returns interest to red beetroot dyes since most pigments are fragile to thermal treatments or with ionizing radiation.

RNA Interference by Ingested Dsrna-Expressing Bacteria to Study Porphyrin Pigmentation in Crassostrea gigas

Porphyrins are a widespread group of pigments in nature which are believed to contribute to shell colors in mollusks. Previous studies have provided candidate genes for porphyrin shell coloration, however, the linkage analysis between functional genes and porphyrin pigmentation remains unclear in mollusks. RNA interference is a powerful molecular tool for analyzing the loss of functions of genes in vivo and alter gene expression. In this study, we used unicellular alga Platymonas subcordiformis and Nitzschia closterium f. minutissima as vectors to feed oysters with Escherichia coli strain HT115 engineered to express double-stranded RNAs targeting specific genes involved in porphyrin synthesis. A strain of Crassostrea gigas with orange shell was used to target key haem pathway genes expression using the aforementioned approach. We show here that feeding the oysters with E. coli, containing dsRNA targeting pigmentation genes, can cause changes in the color of the newly deposited shell. For example, the RNAi knockdown of CgALAS and CgPBGD resulted in the loss of uroporphyrin pigmentation from the shell due to the accumulation of the pigment in the oyster’s mantle. The study probed the crucial role of ALAS and PBGD genes potential functions of uroporphyrin production and shell color pigmentation in C. gigas.

Updates and new medical treatments for vitiligo (Review).

Vitiligo is a multifactorial disease characterized by the loss of skin pigment, which results in achromic macules and patches. There are currently several medical treatments available, which aim to arrest progression and induce skin repigmentation. These treatments alone or combined have exhibited varying degrees of pigmentation, and the majority are safe and effective. All therapies for vitiligo are limited, and no known treatment can consistently produce repigmentation in all patients. Individualized treatment is appropriate according to the location, clinical presentation and the presence of disease activity. The present review summarizes the medical treatments available for vitiligo: Systemic and topic pharmacological therapies, physical and depigmentation treatments. Several treatments are still underway and have not yet been approved. However, due to the promising preliminary results, these are also mentioned in the present review.

Genome-wide association analysis reveals that EDNRB2 causes a dose-dependent loss of pigmentation in ducks

BackgroundBirds have various plumage color patterns, and spot is a common phenotype. Herein, we conducted genome-wide association studies (GWAS) in a population of 225 ducks with different sized black spots to reveal the genetic basis of this phenomenon.Results First, we quantified the black spot phenotype within the duck population. The results showed that the uncolored area of the body surface first appeared on the ventral side. With increasing duck age, the area of the black spots was highly conserved across the whole body surface. The GWAS results identified a 198 kb (Chr4: 10,149,651 bp to 10,348,068 bp) genetic region that was significantly associated with the black spot phenotype. The conditional GWAS and linkage disequilibrium (LD) analysis further narrowed the ultimate candidate region to 167 kb (Chr4: 10,180,939 bp to 10,348,068 bp). A key gene regulating melanoblast migration and differentiation, EDNRB2 (Endothelin B receptor-like), was found in the candidate region and having significant mRNA expression level changes in embryonic duck skin tissue with different spot sizes. The significant SNPs (single nucleotide polymorphisms) associated with the EDNRB2 gene were annotated, and two mutations (Chr4: 10,180,939 T > C and Chr4: 10,190,671 A > T) were found to result in the loss of binding sites for two trans-factors, XBP1 and cMYB. The phenotypic effect of these two mutations suggested that they can regulate the size of black spots in a dose-dependent manner, and Chr4: 10,180,939 T > C was the major allele locus.ConclusionsOur results revealed that EDNRB2 was the gene responsible for the variation in duck body surface spot size. Chr4: 10,180,939 T > C was the major allele that explained 49.5 % (dorsal side) and 32.9 % (ventral side) of the variation in duck body surface spot size, while 32.1 % (dorsal side) and 19.1 % (ventral side) of the variation could be explained by Chr4: 10,190,671 A > T. The trans-factor prediction also suggested that XBP1 and cMYB have the potential to interact with EDNRB2, providing new insights into the mechanism of action of these genes.

Effectiveness of turmeric-enriched pellets to improve the immunity of Clarias batrachus toward motile Aeromonas septicemia disease

Background: Turmeric is known as a natural remedy to improve the immunity of organisms. This study aims to understand the effectiveness of turmeric-enriched pellets to improve the immunity of Clarias batrachus to Aeromonas hydrophila. Methods: The study was conducted from May to August 2020. C. batrachus fingerlings, 7-8 cm total length (TL) and 4-5 g (BW) at baseline, were kept in 30 L aquaria (10 fishes/aquarium; three replicated/treatment). Commercial pellets were mixed with turmeric powder. There were five treatment groups: P0 (control, no turmeric); P1 (0.5 g turmeric per Kg of pellets); P2 (0.7 g/Kg); P3 (0.9 g/Kg); Pp (positive control). Thirty days after being feed with turmeric-enriched pellets, all groups of fish were infected with 0.1 ml (108) of A. hydrophila suspension, intramuscularly. The P0 group did not receive injection, while Pp group were not fed with turmeric-enriched pellets but were infected with the bacteria. Fourteen days after infection, clinical signs and hematology of the fish were studied. Results: Pp fish showed heavy clinical signs of A. hydrophila, such as loss of balance, pigmentation, hemorrhages and ulcers. P0 fish did not show any symptoms, while the treated fish reveled some clinical signs of A. hydrophila to a lesser extent than Pp, indicating that the fish is able to face the A. hydrophila attack. Hematology for Pp fish revealed high white blood cells, indicating that the fish were infected. The blood condition of the P0 fish, as well as those of the turmeric-treated fish were normal. In general, the P3 fish showed the least clinical signs of A. hydrophila and normal blood condition, indicating that P3 treatment is best. Conclusion: The best turmeric dosage to improve the immunity of C. batrachus toward A. hydrophila infection is 0.9 g/Kg pellets.