Immune function of a C-type lectin with long tandem repeats and abundant threonine in the ridgetail white prawn Exopalaemon carinicauda.

C-type lectins (CTLs) are an important class of pattern recognition receptors (PRRs) that exhibit structural and functional diversity in invertebrates. Repetitive DNA sequences are ubiquitous in eukaryotic genomes, representing distinct modes of genome evolution and promoting new gene generation. Our study revealed a new CTL that is composed of two long tandem repeats, abundant threonine, and one carbohydrate recognition domain (CRD) in Exopalaemon carinicauda and has been designated EcTR-CTL. The full-length cDNA of EcTR-CTL was 1242 bp long and had an open reading frame (ORF) of 999 bp that encoded a protein of 332 amino acids. The genome structure of EcTR-CTL contains 4 exons and 3 introns. The length of each repeat unit in EcTR-CTL was 198 bp, which is different from the short tandem repeats reported previously in prawns and crayfish. EcTR-CTL was abundantly expressed in the intestine and hemocytes. After Vibrio parahaemolyticus and white spot syndrome virus (WSSV) challenge, the expression level of EcTR-CTL in the intestine was upregulated. Knockdown of EcTR-CTL downregulated the expression of anti-lipopolysaccharide factor, crustin, and lysozyme during Vibrio infection. The recombinant CRD of EcTR-CTL (rCRD) could bind to bacteria, lipopolysaccharides, and peptidoglycans. Additionally, rCRD can directly bind to WSSV. These findings indicate that 1) CTLs with tandem repeats may be ubiquitous in crustaceans, 2) EcTR-CTL may act as a PRR to participate in the innate immune defense against bacteria via nonself-recognition and antimicrobial peptide regulation, and 3) EcTR-CTL may play a positive or negative role in the process of WSSV infection by capturing virions.

Differential expression of sNPF in male and female eyestalk leading to sex dimorphism of AMP expression in Procambarus clarkii intestine.

Antimicrobial peptide (AMP) is an important component of crustaceans' innate immune system. In this study, a short neuropeptide F (sNPF) gene (Pc-sNPF) and a Forkhead box O (FOXO) gene (PcFOXO) from Procambarus clarkii were identified. Analysis findings showed that the expression level of AMP genes differed between male and female P. clarkii. Furthermore, Pc-sNPF and PcFOXO were related to the sex dimorphism of AMP. Knockdown of Pc-sNPF in the eyestalk significantly upregulated the expression of PcFOXO and two anti-lipopolysaccharide factors (PcALF4 and PcALFL) in the intestine of P. clarkii. The expression of PcFOXO in the intestine of female P. clarkii was higher than in that of males. Results from RNA interference revealed that PcFOXO positively regulated the expression of PcALF4 and PcALFL in the intestine of male and female P. clarkii. In summary, our study showed that differences in Pc-sNPF expression in eyestalk of male and female P. clarkii leading to sex dimorphism of AMP expression in the intestine are mediated by the sNPF-FOXO-AMP signal pathway called the eyestalk-intestine axis.

Synthesis of 2-Arylbenzothiazole and 2-Arylthiazole Derivatives via a Ru-Catalyzed meta-Selective C-H Nitration Reaction.

A Ru-catalyzed meta-selective C-H nitration of 2-arylbenzothiazoles and 2-arylthiazoles has been developed. A wide range of functional groups are tolerated, providing the meta-nitrated products in good to excellent yields using Cu(NO3)2·3H2O as the nitro source. The nitration could be carried out on a gram scale and used for the synthesis of promising therapeutic leads for human African trypanosomiasis.

The complete mitochondrial genome and phylogenetic analysis of Neorhodomela munita.

Neorhodomela munita (Perestenko) Masuda 1982 is distributed in the coastal areas of Shandong and Liaoning in China, and also in Japan. In this study, the complete nucleotide sequence of the circular mitochondrial DNA of the red alga Neorhodomela munita has been determined. The complete mitochondrial DNA sequence of Neorhodomela munita was 25,318 bp in length with an overall GC content of 25.1% and encoded 23 protein-coding genes, two ribosomal RNAs and 24 transfer RNAs. Phylogenetic tree showed that Neorhodomela munita clustered together with Choreocolax polysiphoniae. The phylogenetic analysis may provide a better understanding of the evolution of the Rhodophyta species.

Corneal epithelial-like transdifferentiation of hair follicle stem cells is mediated by pax6 and beta-catenin/Lef-1.

Several types of adult stem cells are capable of transdifferentiaton into other types of tissues. The hair follicle bulge area is an abundant and easily accessible source of pluripotent adult stem cells. We demonstrate that the bulge KSCs have the potential for transdifferentiation into corneal epithelial-like cells. Bulge KSCs isolated by collagen type IV adhesiveness possessed the highest colony formation efficiency (CFE), and expressed specific markers (CD34 and alpha6-integrin). The isolated cells transdifferentiate into corneal epithelial-like cells in conditioned medium containing corneal limbus soluble factors, including their specific marker, keratin12. The transdifferentiation depends on upregulation of pax6 and downregulation of beta-catenin and Lef-1. Furthermore, overexpression of pax6 in bulge KSCs induced their expression of k12. The expressions of beta-catenin and Lef-1 were not suppressed in the pax6-transfected bulge KSCs, but which were downregulated pax6-transfected cells cultured in the conditioned medium. Bulge KSCs may have potential therapeutic application as cell source for the construction of bioengineered corneas.