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Foliar diseases caused by Stemphylium and Colletotrichum species are among the major biotic factors limiting Welsh onion production in Taiwan. Owing to concerns about the environment and the development of pathogen resistance to existing fungicides, biological control using endophytes is emerging as an eco-friendly alternative to chemical control. The aim of the present study was to isolate endophytes from healthy Welsh onion leaves and investigate their antagonistic potential against the major phytopathogenic fungi associated with Welsh onion plants in Taiwan. A total of 109 bacterial and 31 fungal strains were isolated from healthy Welsh onion leaves and assigned to 16 bacterial and nine fungal genera using morphological and molecular characterization based on DNA sequence data obtained from nuclear internal transcribed spacer (nrITS) (fungi) and 16S rRNA (bacteria). Evaluation of these endophytic isolates for biocontrol activity against leaf blight pathogens Colletotrichum spaethianum strain SX15-2 and Stemphylium vesicarium strain SX20-2 by dual culture assay and greenhouse experiments resulted in the identification of two bacterial isolates (GFB08 and LFB28) and two fungal isolates (GFF06 and GFF08) as promising antagonists to leaf blight pathogens. Among the four selected isolates, Bacillus strain GFB08 exhibited the highest disease control in the greenhouse study. Therefore, Bacillus strain GFB08 was further evaluated to understand the mechanism underlying its biocontrol efficacy. A phylogenetic analysis based on six genes identified Bacillus strain GFB08 as B. velezensis. The presence of antimicrobial peptide genes (baer, bamC, bmyB, dfnA, fenD, ituC, mlna, and srfAA) and the secretion of several cell wall degrading enzymes (CWDEs), including cellulase and protease, confirmed the antifungal nature of B. velezensis strain GFB08. Leaf blight disease suppression by preventive and curative assays indicated that B. velezensis strain GFB08 has preventive efficacy on C. spaethianum strain SX15-2 and both preventive and curative efficacy on S. vesicarium strain SX20-2. Overall, the current study revealed that healthy Welsh onion leaves harbour diverse bacterial and fungal endophytes, among which the endophytic bacterial strain, B. velezensis strain GFB08, could potentially be used as a biocontrol agent to manage the leaf blight diseases of Welsh onion in Taiwan. [ABSTRACT FROM AUTHOR]

Short open reading frames (sORFs) are a newly identified family of genes, and the functions of most sORF genes and their encoded peptides (SEPs) are still unknown. In this study, two ATP synthase subunits were identified in kuruma shrimp (Marsupenaeus japonicus) as SEPs, namely MjATP5I and MjATP5L. They were widely distributed in all of the tested tissues of shrimp and upregulated in hemocytes and intestines in response to WSSV challenge. The injection of recombinant proteins (rMjATP5I and rMjATP5L) increased the expression of Ie1 and Vp28, while the knockdown of MjATP5I and MjATP5L decreased the expression of Ie1 and Vp28. All of the results suggest that MjATP5I and MjATP5L were beneficial for WSSV replication. Further exploration found that MjATP5I and MjATP5L RNAi significantly improved the shrimp survival rates, reduced ATP production, and upregulated the expression of antimicrobial peptide genes post viral challenge, and the two ATPase subunits and Relish negatively regulated each other. These results reveal that MjATP5I and MjATP5L facilitated WSSV duplication by regulating the production of ATP contents and the expression of antimicrobial peptide genes in shrimp. [ABSTRACT FROM AUTHOR]

Foliar diseases caused by Stemphylium and Colletotrichum species are among the major biotic factors limiting Welsh onion production in Taiwan. Owing to concerns about the environment and the development of pathogen resistance to existing fungicides, biological control using endophytes is emerging as an eco-friendly alternative to chemical control. The aim of the present study was to isolate endophytes from healthy Welsh onion leaves and investigate their antagonistic potential against the major phytopathogenic fungi associated with Welsh onion plants in Taiwan. A total of 109 bacterial and 31 fungal strains were isolated from healthy Welsh onion leaves and assigned to 16 bacterial and nine fungal genera using morphological and molecular characterization based on DNA sequence data obtained from nuclear internal transcribed spacer (nrITS) (fungi) and 16S rRNA (bacteria). Evaluation of these endophytic isolates for biocontrol activity against leaf blight pathogens Colletotrichum spaethianum strain SX15-2 and Stemphylium vesicarium strain SX20-2 by dual culture assay and greenhouse experiments resulted in the identification of two bacterial isolates (GFB08 and LFB28) and two fungal isolates (GFF06 and GFF08) as promising antagonists to leaf blight pathogens. Among the four selected isolates, Bacillus strain GFB08 exhibited the highest disease control in the greenhouse study. Therefore, Bacillus strain GFB08 was further evaluated to understand the mechanism underlying its biocontrol efficacy. A phylogenetic analysis based on six genes identified Bacillus strain GFB08 as B. velezensis. The presence of antimicrobial peptide genes (baer, bamC, bmyB, dfnA, fenD, ituC, mlna, and srfAA) and the secretion of several cell wall degrading enzymes (CWDEs), including cellulase and protease, confirmed the antifungal nature of B. velezensis strain GFB08. Leaf blight disease suppression by preventive and curative assays indicated that B. velezensis strain GFB08 has preventive efficacy on C. spaethianum strain SX15-2 and both preventive and curative efficacy on S. vesicarium strain SX20-2. Overall, the current study revealed that healthy Welsh onion leaves harbour diverse bacterial and fungal endophytes, among which the endophytic bacterial strain, B. velezensis strain GFB08, could potentially be used as a biocontrol agent to manage the leaf blight diseases of Welsh onion in Taiwan.

The human amniotic membrane has been successfully used in human ocular reconstruction. Several studies have demonstrated its properties, including antimicrobial features. As a result of the restricted availability of human amniotic membrane for veterinary use, canine amniotic membrane has become an attractive alternative. Clinical studies of the application of canine amniotic membrane in animals and the understanding of its biological properties are limited. This study aimed to determine the expression of peptide genes of natural antimicrobials in canine amniotic membrane. Expressions of canine β-defensin 1, 102, and 103, and canine Elafin were determined in healthy puppies by real-time quantitative polymerase chain reaction. Canine β-defensin 1, 103, and Elafin were expressed in all samples, possibly suggesting a role in the innate immune system of normal canine amniotic membrane. Further investigations of protein expression and localization are recommended. [ABSTRACT FROM AUTHOR]

The human amniotic membrane has been successfully used in human ocular reconstruction. Several studies have demonstrated its properties, including antimicrobial features. As a result of the restricted availability of human amniotic membrane for veterinary use, canine amniotic membrane has become an attractive alternative. Clinical studies of the application of canine amniotic membrane in animals and the understanding of its biological properties are limited. This study aimed to determine the expression of peptide genes of natural antimicrobials in canine amniotic membrane. Expressions of canine β-defensin 1, 102, and 103, and canine Elafin were determined in healthy puppies by real-time quantitative polymerase chain reaction. Canine β-defensin 1, 103, and Elafin were expressed in all samples, possibly suggesting a role in the innate immune system of normal canine amniotic membrane. Further investigations of protein expression and localization are recommended.

We studied the effect of 1α 25 dihydroxy vitamin D3 (1α,25(OH)2D3), the active form of vitamin D3, on the expression of cathelicidin (CAMP), defensin-α3 (DEFα3) and vitamin D receptor (VDR) genes in neutrophils cultured with or without Mycobacterium tuberculosis (Mtb) from pulmonary tuberculosis patients and healthy controls. Vitamin D3 significantly enhanced the CAMP, DEF-α3 and VDR mRNA expression in the neutrophils of both the study groups (P < 0.05). Moreover, significantly upregulated CAMP expression was observed in vitamin D3-treated neutrophils infected with Mtb (P < 0.05) in both the study groups. These findings suggest that vitamin D3 enhances innate immunity by increasing the expression of the CAMP gene, which might inhibit the growth of Mtb at the site of infection. [ABSTRACT FROM AUTHOR]

Highlights: [•] Identifiying a cDNA coding for Lysin motif containing protein (PcLysM) from crayfish. [•] The transcription of PcLysM was upregulated by V. anguillarum and S. aureus. [•] PcLysM could bind to bacteria and yeast. [•] It could bind to peptidoglycans from different bacteria, and chitin. [•] PcLysM might function in antibacterial innate immunity of the crayfish P. clarkii. [Copyright &y& Elsevier]

Abstract: Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) is a key signaling adaptor protein not only for the TNFR superfamily but also for the Interleukin-1 receptor/Toll-like receptor (IL-1/TLR) superfamily. To investigate TRAF6 function in invertebrate innate immune responses, Litopenaeus vannamei TRAF6 (LvTRAF6) was identified and characterized. The full-length cDNA of LvTRAF6 is 2823bp long, with an open reading frame (ORF) encoding a putative protein of 594 amino acids, including a RING-type Zinc finger, two TRAF-type Zinc fingers, a coiled–coil region, and a meprin and TRAF homology (MATH) domain. The overall amino acid sequence identity between LvTRAF6 and other known TRAF6s is 22.2–33.3%. Dual luciferase reporter assays in Drosophila S2 cells revealed that LvTRAF6 could activate the promoters of antimicrobial peptide genes (AMPs), including Drosophila Attacin A and Drosomycin, and shrimp Penaeidins. Real-time quantitative PCR (qPCR) indicated that LvTRAF6 was constitutively expressed in various tissues of L. vannamei. After Vibrio alginolyticus and white spot syndrome virus (WSSV) challenge, LvTRAF6 was down-regulated, though with different expression patterns in the intestine compared to other tissues. After WSSV challenge, LvTRAF6 was up-regulated 2.7- and 2.3-fold over the control at 3h in gills and hepatopancreas, respectively. These results indicated that LvTRAF6 may play a crucial role in antibacterial and antiviral responses via regulation of AMP gene expression. [ABSTRACT FROM AUTHOR]

Abstract: Although Bombyx mori systematic immunity is extensively studied, little is known about the silkworm''s intestine-specific responses to bacterial infection. Antimicrobial peptides (AMPs) gene expression analysis of B. mori intestinal tissue to oral infection with the Gram-positive (Staphylococcus aureus) and -negative (Escherichia coli) bacteria revealed that there is specificity in the interaction between host immune responses and parasite types. Neither Att1 nor Leb could be stimulated by S. aureus and E. coli. However, CecA1, Glo1, Glo2, Glo3, Glo4 and Lys, could only be trigged by S. aureus. On the contrary, E. coli stimulation caused the decrease in the expression of CecA1, Glo3 and Glo4 in some time points. Interestingly, there is regional specificity in the silkworm local gut immunity. During the immune response, the increase in Def, Hem and LLP3 was only detected in the foregut and midgut. For CecB1, CecD, LLP2 and Mor, after orally administered with E. coli, the up-regulation was only limited in the midgut and hindgut. CecE was the only AMP that positively responses to the both bacteria in all the testing situations. With development, the expression levels of the AMPs were also changed dramatically. That is, at spinning and prepupa stages, a large increase in the expression of CecA1, CecB1, CecD, CecE, Glo1, Glo2, Glo3, Glo4, Leb, Def, Hem, Mor and Lys was detected in the gut. Unexpectedly, in addition to the IMD pathway genes, the Toll and JAK/STAT pathway genes in the silkworm gut can also be activated by microbial oral infection. But in the developmental course, corresponding to the increase in expression of AMPs at spinning and prepupa stages, only the Toll pathway genes in the gut exhibit the similar increasing trend. Our results imply that the immune responses in the silkworm gut are synergistically regulated by the Toll, JAK/STAT and IMD pathways. However, as the time for approaching pupation, the Toll pathway may play a role in the AMPs expression. [Copyright &y& Elsevier]

The article presents a study which examines the correlation of differential expression, and the gene transcriptional activity of antimicrobial peptide (AMP) genes in silkworm, Bombyx mori, which have various amounts of Rel family proteins. The methods used, and the results obtained by the study are discussed. The study reveals that various types of peptidoglycans (PGNs) caused differential activation of AMP genes, while lipopolysaccharide (LPS) elicited expression of immune genes in the silkworm.

In shrimp, several glutathione peroxidase (GPX) genes have been cloned and functionally studied. Increasing evidence suggests the genes' involvement in white spot syndrome virus (WSSV)- or Vibrio alginolyticus-infection resistance. In the present study, a novel GXP gene (LvGPX3) was cloned in Litopenaeus vannamei. Promoter of LvGPX3 was activated by NF-E2-related factor 2. Further study showed that LvGPX3 expression was evidently accelerated by oxidative stress or WSSV or V. alginolyticus infection. Consistently, downregulated expression of LvGPX3 increased the cumulative mortality of WSSV- or V. alginolyticus-infected shrimp. Similar results occurred in shrimp suffering from oxidative stress. Moreover, LvGPX3 was important for enhancing Antimicrobial peptide (AMP) gene expression in S2 cells with lipopolysaccharide treatment. Further, knockdown of LvGPX3 expression significantly suppressed expression of AMPs, such as Penaeidins 2a, Penaeidins 3a and anti-lipopolysaccharide factor 1 in shrimp. AMPs have been proven to be engaged in shrimp WSSV- or V. alginolyticus-infection resistance; it was inferred that LvGPX3 might enhance shrimp immune response under immune challenges, such as increasing expression of AMPs. The regulation mechanism remains to be further studied. [ABSTRACT FROM AUTHOR]

It has been reported that a high population density alters insect prophylactic immunity. Bursicon plays a key role in the prophylactic immunity of newly emerged adults. In this paper, full-length cDNAs encoding the alpha and beta subunits of bursicon in Mythimna separata larvae (Msburs α and Msburs β) were identified. The cDNAs of Msburs α and Msburs β contain open reading frames (ORFs) encoding 145- and 139-amino acid residue proteins, respectively. Multiple alignment sequences and phylogenetic analysis indicated that Msbursicons (Msburs α and Msburs β) are orthologous to bursicons in other lepidopterans. The Msbursicons were expressed throughout all developmental states with higher relative expression during the egg, pupae, and adult stages. Msbursicons (Msburs α and Msburs β) were highly expressed in the ventral nerve cord and brain relative to other tested tissues. Msbursicon expression of larvae subject to high-density treatment (10 larvae per jar) was significantly increased compared with that of the larvae subject to low-density treatment (1 larva per jar) in the whole fourth and fifth instar stages. The trend in the expression of the antimicrobial peptide (AMP) genes cecropin C and defensin in the test stage was accorded and delayed with increased expression of bursicons. Silencing Msburs α (or Msburs β) expression by dsRNA injection in larvae subject to high-density treatment significantly decreased the expression levels of the cecropin C and defensin genes. Recombinant Msbursicon homodimers significantly induced the expression of the cecropin C and defensin genes. There was a notable decrease in the survival rate of the Msburs α (or Msburs β or Mscecropin C or Msdefensin) knockdown larvae infected by Beauveria thuringiensis. Our findings provide the first insights into how larval density mediates AMP gene expression, which subsequently affects the prophylactic immunity of insects under high-density conditions. • Bursicon genes (bursα and bursβ) from Oriental armyworm, M. separata was first isolated and identified. • High density significantly enhanced in bursicon genes expression in the larvae of M. separata. • The changed trend in AMPs expression of larvae from different density treatments was accorded and delayed with increased expression of bursicons. • Significant down-regulated (or up-regulated) expression of AMPs in the Msbursicon gene knockdown (or injection their homodimers) larvae. • There was notable decrease in the survival against Beauveria thuringiensis infection of the bursion (or AMPs) gene knockdown high density larvae. [ABSTRACT FROM AUTHOR]