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ABSTRACT: Serine proteases (SPs), with their homologues (SPHs), a family of multifunctional proteins, play a crucial role in innate immune system. In our present study, we made an appropriate correction: serine protease homologue PtcSPH (Li et al., 2012a) obtained from the swimming crab Portunus trituberculatus was actually a serine protease and re-designated as PtcSP. Sequence analysis revealed PtcSP and PtSP (Li et al., 2012b) might be encoded by the same genomic locus and generated by alternative splicing of the pre-mRNA. Eight exons were identified in genomic DNA sequence of PtcSP. A comprehensive phylogenetic analysis was made combined with our previous reports (Cui et al., 2010; Li et al., 2012a, b). The result showed SPs and SPHs of P. trituberculatus had different origins in gene evolution. To further characterize the function(s) of proteins, the recombinant serine proteases or homologues were assayed for various biological functions: proteinase activity, antimicrobial activity and microorganisms binding activity. The recombinant protein PtcSP exhibited trypsin-like protease activity and antibacterial activity. PtSPH1 (Li et al., 2012b) lacked proteolytic activity but displayed binding activity to yeast and the crab pathogenic bacterium, Vibrio alginolyticus. Further, the N-terminal clip domain of PtcSP had antibacterial activity and the C-terminal SP-like domain had trypsin-like protease activity.
Fish & Shellfish Immunology 05/2013; · 3.32 Impact Factor
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ABSTRACT: Anti-lipopolysaccharide factor (ALF) is an important antimicrobial peptide (AMP) that can bind and neutralize major component of Gram-negative bacteria cell wall, lipopolysaccharide (LPS). Seven isoforms of anti-lipopolysaccharide factors (PtALF 1-7) were previously identified from the swimming crab Portunus trituberculatus in our laboratory. Here, polymorphisms of PtALF1-7 were detected and their association with resistance/susceptibility to Vibrio alginolyticus (a main Gram-negative bacteria causing high mortality in P. trituberculatus) were investigated. We identified 127, 96, 103, 53 and 158 single nucleotide polymorphisms (SNPs) in genomic fragments of PtALF1-3, PtALF4, PtALF5, PtALF6 and PtALF7, respectively. Among them, totally sixteen SNPs were significantly associated with resistance/susceptibility to V. alginolyticus (P < 0.05). Of these sixteen SNPs, most were located in introns and noncoding exons, while two synonymous SNPs and one nonsynonymous SNP were in coding exons. Additionally, simple sequence repeats (SSRs) were only identified in introns and noncoding exons of PtALF4, PtALF5 and PtALF7. Although no significant difference of allele frequencies was found, these SSRs had different polymorphic alleles according to the repeat number between susceptible and resistant stocks. After further confirmation, polymorphisms investigated here might be applied as potential molecular markers for future selection of resistant strains to diseases caused by Gram-negative bacteria.
Fish & Shellfish Immunology 04/2013; · 3.32 Impact Factor
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ABSTRACT: Anti-lipopolysaccharide factors (ALFs), as the potent antimicrobial peptides, are becoming predominant candidates for potential therapeutic agents of bacterial and viral diseases. In this study, a unique isoform of ALF (PtALF7) was identified from hemocytes cDNA library of the swimming crab Portunus trituberculatus. The PtALF7 cDNA contained an open reading frame (ORF) of 372 bp encoding 123 amino acids. The deduced peptide of PtALF7 shared high similarity with our previously reported PtALF1-3 but low with PtALF4-6. The PtALF7 gene consisted of three exons interrupted by two introns, and was clearly transcribed from different genomic loci compared with other PtALF isoforms. Totally 128 SNPs including 12 in coding region and 116 in noncoding region were detected in PtALF7 gene by direct sequencing of 20 samples. The mRNA expression of PtALF7 transcript was primarily observed in hemocytes followed by gill and eyestalk, but barely detectable in hepatopancreas. After challenge with Vibrio alginolyticus, a main pathogen causing high mortality in P. trituberculatus, the PtALF7 transcript in hemocytes showed a clear time-dependent response expression pattern with obvious decrease at 6 h and significant increase at 24 h. The recombinant PtALF7 protein exhibited antimicrobial activity against the test Gram-negative and Gram-positive bacteria, but did not inhibit the growth of fungus Pichia pastoris. These results together indicate a potential involvement for PtALF7 in the innate immune response of P. trituberculatus.
Fish & Shellfish Immunology 12/2012; · 3.32 Impact Factor
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ABSTRACT: Anti-lipopolysaccharide factors (ALFs), exhibiting binding and neutralizing activities to lipopolysaccharide (LPS), are the potent antimicrobial peptides of innate immunity in crustaceans. In this study, a unique isoform of ALF (PtALF6) was identified from eyestalk cDNA library of the swimming crab Portunus trituberculatus. The full-length cDNA of PtALF6 was 669 bp encoding 115 amino acids, relatively short to other known ALFs. The deduced peptide of PtALF6 was conserved; it contained the signal peptide and LPS-binding domain, especially the two conserved cysteine residues at both ends of the domain. Predicted tertiary structures of PtALF6 containing four β-strands and three α-helices were similar to that described in Limulus polyphemus. The genomic fragment of PtALF6 contained three exons separated by two introns. Unlike most ALFs expressed in hemocytes, PtALF6 transcript was predominantly detected in gill with 14.05-fold higher than that in hemocytes. After challenge with Vibrio alginolyticus, the temporal expression level of PtALF6 transcript in hemocytes showed a clear time-dependent response expression pattern with two significant peaks at 12 h and 32 h post-injection. The recombinant PtALF6 protein revealed antimicrobial activity against the test Gram-negative and Gram-positive bacteria, but did not inhibit the growth of fungus Pichia pastoris. These results together indicate that PtALF6 is a potential antimicrobial protein against Gram-negative and Gram-positive bacteria infection, and may play an important role in innate immune response of P. trituberculatus.
Fish & Shellfish Immunology 12/2012; · 3.32 Impact Factor
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ABSTRACT: BACKGROUND: The evolutionary history and relationships of the mud shrimps (Crustacea: Decapoda: Gebiidea and Axiidea) are contentious, with previous attempts revealing mixed results. The mud shrimps were once classified in the infraorder Thalassinidea. Recent molecular phylogenetic analyses, however, suggest separation of the group into two individual infraorders, Gebiidea and Axiidea. Mitochondrial (mt) genome sequence and structure can be especially powerful in resolving higher systematic relationships that may offer new insights into the phylogeny of the mud shrimps and the other decapod infraorders, and test the hypothesis of dividing the mud shrimps into two infraorders. RESULTS: We present the complete mitochondrial genome sequences of five mud shrimps, Austinogebia edulis, Upogebia major, Thalassina kelanang (Gebiidea), Nihonotrypaea thermophilus and Neaxius glyptocercus (Axiidea). All five genomes encode a standard set of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a putative control region. Except for T. kelanang, mud shrimp mitochondrial genomes exhibited rearrangements and novel patterns compared to the pancrustacean ground pattern. Each of the two Gebiidea species (A. edulis and U. major) and two Axiidea species (N. glyptocercus and N. thermophiles) share unique gene order specific to their infraorders and analyses further suggest these two derived gene orders have evolved independently. Phylogenetic analyses based on the concatenated nucleotide and amino acid sequences of 13 protein-coding genes indicate the possible polyphyly of mud shrimps, supporting the division of the group into two infraorders. However, the infraordinal relationships among the Gebiidea and Axiidea, and other reptants are poorly resolved. The inclusion of mt genome from more taxa, in particular the reptant infraorders Polychelida and Glypheidea is required in further analysis. CONCLUSIONS: Phylogenetic analyses on the mt genome sequences and the distinct gene orders provide further evidences for the divergence between the two mud shrimp infraorders, Gebiidea and Axiidea, corroborating previous molecular phylogeny and justifying their infraordinal status. Mitochondrial genome sequences appear to be promising markers for resolving phylogenetic issues concerning decapod crustaceans that warrant further investigations and our present study has also provided further information concerning the mt genome evolution of the Decapoda.
BMC Genomics 11/2012; 13(1):631. · 4.07 Impact Factor
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ABSTRACT: Crustins are cationic, cysteine-rich antimicrobial proteins, containing a single whey acidic protein (WAP) domain in the C-terminal end. Different from the reported Ptcrustin in the hemocytes, two novel crustin genes (PtCrustin2 and PtCrustin3) were cloned completely from the eyestalk cDNA library of Portunus trituberculatus in this study. All PtCrustins share the consensus cysteine motif and are considered as Type I crustins. Four exons and three introns are identified in genomic DNA sequence of PtCrustin3 while three exons and two introns in PtCrustin2. The mRNA transcripts of PtCrustin2 and PtCrustin3 are mainly detected in eyestalk and gills, but not in hemocytes. Although both PtCrutins are up-regulated after challenge of three microorganisms, PtCrustin3 seems to respond more quickly to microbial challenge than Ptcrustin2. Unlike most crustins, both recombinant PtCrustin2 and PtCrustin3 exhibit antibacterial activity against Gram-positive bacteria Micrococcus luteus and Staphyloccocus aureus and Gram-negative bacterium Pseudomonas aeruginosa. In addition, rPtCrustin2 is moderately active against yeast Pichia pastoris and rPtCrustin3 show significant activity against Gram-negative bacterium Vibrio alginolyticus. These results indicate that PtCrustin2 and PtCrustin3 are two novel crustins and play different roles in immune response of P. trituberculatus against microbial challenge.
Fish & Shellfish Immunology 08/2012; 33(4):937-45. · 3.32 Impact Factor
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ABSTRACT: Thirty polymorphic microsatellite markers for swimming crab P. trituberculatus are developed from EST sequences, genomic libraries and cross-species amplification in P. pelagicus, respectively. They are characterized using 24 P. trituberculatus individuals from Yingkou natural population. The number of alleles per locus range from 4 to 21 with a mean number of 10.83.
The observed and expected heterozygosities range from 0.250 to 1.000 and from 0.365 to 0.945, respectively. Five loci departed
significantly from HWE (P<0.05). The genomic-SSRs and EST-SSRs show similar levels of polymorphism for both the average number of alleles (11 alleles
vs. 10 alleles) and average PIC values (PIC=0.780 vs. PIC=0.776). These microsatellite loci from different sources will
contribute to improve research on the genetic conservation of P. trituberculatus.
Keywords
Portunus trituberculatus
–Microsatellites–Polymorphism
Conservation Genetics Resources 05/2012; 4(2):251-255. · 0.49 Impact Factor
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ABSTRACT: Although Pampus minor has been classified as a new species, it still remains controversial. Was used a DNA barcoding technique based on homologous
sequence analysis of the16S and COI genes to clarify the confusion over the identification of this species. Among 12 individuals whose genetic distance was 0.002,
two haplotypes were found. According to the 16S sequences, the genetic distances ranged from 0.121 to 0.133 between P. minor and other Pampus species. Although the same the genetic distance between the two P. minor haplotypes was generated using COI sequences, the haplotype of Pm22-23, Pm28, and Pm32-33 was the same as that of Pci EF607462 and EF607466, while the haplotype
of Pm24-27 and Pm29-31 was the same as that of Pci EF607461 and EF607463-65. In addition, the genetic distance ranged only
from 0.002 to 0.005 between P. minor and Pa EF607460 and EF607458. Apart from this, the interspecies genetic distances varied from 0.135 to 0.143 between P. minor and other Pampus species according to the COI sequences. Phylogenetic trees, using combined 16S and COI data, strongly support the viewpoint that all the P. minor individuals form one clade that is in a sister position to Pampus sp. individuals (EU357803, FJ434342-FJ434343, and FJ652423-FJ652427).
Keyword
Pampus minor
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COI
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16S
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Chinese Journal of Oceanology and Limnology 04/2012; 28(6):1266-1274. · 0.50 Impact Factor
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ABSTRACT: Perciformes, the largest order of vertebrates with 20 suborders, is the most diverse fish order that dominates vertebrate
ocean life. The complete mitochondrial control region (CR) of Trichiurus japonicus (Trichiuridae, Scombroidei) and Pampus sp. (Stromateidae, Stromateoidei) were amplified and sequenced. Together with data from GenBank, the tandem repeats in the
mitochondrial CR from 48 species, which covered nine suborders of Perciformes, are reported in this study. The tandem repeats
tend to be long in the suborder Percoidei and Stromateoidei. The identical repeats in 21 species of Cichlidae suggest a common
origin and have existed before species divergence. Larimichthys crocea shows tandem repeats instead of the typical structure of the central conserved sequence blocks, which was first reported
in Perciformes and vertebrates. This might have resulted from interruption of the polymerase activity during the H-strand
synthesis. The four broader patterns presented here for the tandem repeats, including those in both the 5′ and 3′ ends, only
in the either 5′ or 3′ end, and in the central conserved domain of the control region, will be useful for understanding the
evolution of species.
KeywordmtDNA-control region-tandem repeats-Perciformes-evolution
Chinese Journal of Oceanology and Limnology 04/2012; 28(4):785-794. · 0.50 Impact Factor
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ABSTRACT: Concerning the nomenclature, most problems arise from the great confusion due to the morphological similarities in Pampus. Twenty-five individuals in Pampus were sampled from different localities about 2,000km apart along the coast of China covering the Yellow Sea, the East China
Sea and the South China Sea. The sequences of cytochrome c oxidase I (COI) and 16S rRNA (16S) genes of the mitogenomes were determined. Combined with the morphological characteristics, five Pampus species, P. minor, P. punctatissimus, P. chinensis, P. cinereus and Pampus sp., were identified. The genetic distance of intraspecies ranged from 0.000 to 0.004, while it varied from 0.012 to 0.133
for interspecies based on the 16S sequences. For COI sequence data analysis, the genetic distance of intraspecies ranged from 0.000 to 0.005, while it varied from 0.057 to 0.162
for interspecies. Phylogenetic trees showed that all Pampus fishes reciprocally constituted a monophyletic group with strong support. The sister-group relationships between P. minor and Pampus sp. and between P. chinensis and P. punctatissimus were revealed respectively. In the current GenBank data, P. minor is considered P. cinereus or P. argenteus by mistake. For the lack of a P. echinogaster specimen, we cannot decide on the name of Pampus sp. as P. argenteus or P. echinogaster.
Ichthyological Research 04/2012; 57(1):32-39. · 0.87 Impact Factor
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ABSTRACT: A new isoform of anti-lipopolysaccharide factor (PtALF5) was cloned from eyestalk cDNA library of swimming crab Portunus trituberculatus. The full-length cDNA of PtALF5 was 1045 bp encoding 120 amino acids. PtALF5 shared lower amino acid similarity with other ALFs, yet it contained the conserved LPS-binding domain and was clearly member of the ALF family. The genomic fragment of PtALF5 contained two exons separated by one intron. Several tandem repeats were found in intron. The mRNA transcript of PtALF5 was predominantly expressed in the hemocytes but barely detectable in muscle. After challenge with Vibrio alginolyticus, a main pathogen causing high mortality in P. trituberculatus, the PtALF5 transcript in hemocytes showed a clear time-dependent response expression pattern with obvious decrease at 6 h and significant increase at 24 h. The recombinant PtALF5 protein revealed antimicrobial activity against Gram-negative bacteria V. alginolyticus and Pseudomonas aeruginosa, but did not inhibit the growth of the tested Gram-positive bacteria and fungus. These results together suggest that PtALF5 is a potent antibacterial protein against Gram-negative bacteria infection, and might function as a promising therapeutic agent in disease control of crab aquaculture.
Fish & Shellfish Immunology 04/2012; 33(1):85-91. · 3.32 Impact Factor
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ABSTRACT: Serine protease inhibitors (Serpins) play a key role in diverse immune biological processes. A serine protease inhibitor (Serpin), namely PtSerpin, was identified from the haemocyte cDNA library of swimming crab Portunus trituberculatus. The full-length PtSerpin cDNA was 1593 bp, including an open reading frame (ORF) of 1227 bp encoding a polypeptide of 408 amino acids with estimated molecular mass of 45.048 kDa and theoretical isoelectric point of 7.23. Predicted tertiary structure of PtSerpin contained three β-sheets and nine α-helices. Multiple sequence alignment revealed that deduced amino acid sequence of PtSerpin shared the highest similarity with serpin SPI from green mud crab Scylla paramamosain (SpSerpin). Phylogenetic analysis supported PtSerpin and SpSerpin were closely related to serpins from Penaeus monodon and Daphnia pulex while other decapods formed a separate group. Although the mRNA transcripts of PtSerpin could be detected in all the examined tissues, the higher levels were present in haemocytes and gills which are the major organs respond to pathogenic microorganism. After challenged by Vibrio alginolyticus, Micrococcus luteus and Pichia pastoris, the temporal expression of PtSerpin gene in haemocytes showed different activation times against bacteria and fungi within the experimental period of 72 h. These findings suggest that PtSerpin is involved in the antibacterial defense mechanism of P. trituberculatus crab.
Fish & Shellfish Immunology 04/2012; 32(4):544-50. · 3.32 Impact Factor
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ABSTRACT: Four genes including three clip domain serine proteases (PtcSP1, PtcSP2 and PtcSP3) and one clip domain serine protease homologue (PtcSPH) of the swimming crab Portunus trituberculatus (Decapoda: Brachyura: Portunidae) were characterized based on analysis of expressed sequence tags from haemocytes and eyestalk cDNA libraries. The relative four peptidases, which share high structural similarity to the clip-SPs of other arthropod species, appeared to possess a clip domain at the N-terminus and an enzymatically active serine protease domain at the C-terminus except PtcSPH for its second catalytic residue Asp. (D) replaced by Ala (A). Alignment among the four full-sequences showed that PtcSP2 and PtcSP3 had the highest identical score (58%) while the similarity of other sequences was lower than 24%. The mRNA transcripts of PtcSPs and PtcSPH could be detected widely in all the examined tissues with remarkable different expression levels. The temporal expressions of PtcSPs and PtcSPH demonstrated different time-dependent expression pattern post Vibrio alginolyticus, Micrococcus luteus, and Pichia pastoris challenge. Especially, the expression of PtcSPH transcripts showed greater change against V. alginolyticus compared with the other two microorganisms. These findings suggest that PtcSPs and PtcSPH play different roles in the antibacterial defence mechanism of P. trituberculatus crab.
Fish & Shellfish Immunology 04/2012; 32(4):565-71. · 3.32 Impact Factor
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ABSTRACT: Previously, we had reported two homologues of the thioredoxin (Trx) super-family (PtTrx1 and PtTrx2) identified from eyestalk and haemocytes cDNA library of swimming crab Portunus trituberculatus, respectively. It was the first report of two thioredoxin homologues from the same crustacean species. Here, we focused on the molecular characterization, genomic organization and expression pattern of PtTrx1 and PtTrx2. The full-length cDNA sequences of PtTrx1 and PtTrx2 were 739 and 1300 bp, encoding 105 and 133 amino acids, respectively. They both had a conserved CGPC active site and highly similar tertiary structures, which containing four β-sheets and four α-helixes. Specifically, PtTrx2 was encoded by a nuclear gene and its cellular localization was targeted to mitochondria by an N-terminal mitochondrial pre-sequence. Sequence analysis revealed PtTrx1 and PtTrx2 were encoded by different genomic locus. As the first analyzed genomic structure of PtTrxs in crustaceans, two introns with microsatellites were found in the open reading frame region of these genes. Quantitative real-time PCR analysis revealed the mRNA expression of PtTrx1 transcripts were mainly detected in gill, while, PtTrx2 in eyestalk and gill. The temporal expression levels of PtTrxs transcripts in haemocytes showed different expression patterns after challenge with Vibrio alginolyticus, Micrococcus luteus and Pichia pastoris. These results together indicate that PtTrxs should be involved in the responses to pathogen challenge of P. trituberculatus.
Fish & Shellfish Immunology 02/2012; 32(5):855-61. · 3.32 Impact Factor
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ABSTRACT: Anti-lipopolysaccharide factors (ALFs) are the potent antimicrobial peptides that can bind and neutralize lipopolysaccharide (LPS). In this study, a new isoform of the ALF homologs (PtALF4) was cloned from eyestalk cDNA library of swimming crab Portunus trituberculatus. PtALF4 shared lower amino acid similarity with other ALFs, yet it contained the conserved LPS-binding domain and was clearly member of the ALF family. The genomic sequence of PtALF4 consisted of three exons interrupted by two introns. Several tandem repeats were found in both introns. Unlike most ALFs expressed in hemocytes, PtALF4 transcript was predominantly detected in eyestalk. After challenge with Vibrio alginolyticus, the temporal expression level of PtALF4 transcript in hemocytes showed a clear time-dependent response expression pattern with two significant peaks. The recombinant proteins of PtALF1, PtALF3 and PtALF4 revealed different antimicrobial activities against bacteria or fungus. These results together suggest that PtALF isoforms might be potent immune effectors to provide multiple protective functions against invading bacteria or fungus in P. trituberculatus.
Fish & Shellfish Immunology 02/2012; 32(5):724-31. · 3.32 Impact Factor
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ABSTRACT: In our previous studies, five serine proteases containing clip domain were characterized from the swimming crab Portunus trituberculatus. To further investigate the characterization and function of serine proteases, one serine protease (PtSP) and one serine protease homolog (PtSPH1) without clip domain were identified from haemocytes cDNA library in this paper. They both possessed an SP or SP-like domain at the C-terminal. In contrast to PtSP, absence of Ser catalytic residue resulted in the loss of serine protease activity of PtSPH1. Phylogenetic analysis suggested either SPs or SPHs might not have a single origin in gene evolution. Six introns presented in PtSP genomic DNA with one uncommon splice site (GG) was discovered at exon 1/intron 1 boundary region. Four introns with common splice sites were found in PtSPH1 genomic DNA. RT-PCR results showed that PtSP mRNA was mainly distributed in haemocytes, gill and eyestalk, whereas PtSPH1 transcript was mainly expressed in stomach. PtSP showed slight increase during the first 48 h compared to control groups except 8 h point after Micrococcus luteus challenge. However, significant up-regulation was observed in the expression level of PtSPH1 challenged by Gram-negative bacteria Vibrio alginolyticus, Gram-positive bacteria M. luteus and fungi Pichia pastoris during the first 48 h. It indicates that PtSPH1 might be more sensitive to microorganism challenges compared with PtSP.
Fish & Shellfish Immunology 01/2012; 32(5):683-92. · 3.32 Impact Factor
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ABSTRACT: Among all the serine proteinase inhibitor families (SPIs), the pacifastin-related inhibitor is seldom isolated. A pacifastin-related SPI named as PtPLC was identified from the swimming crab Portunus trituberculatus in this study. The full-length of PtPLC was cloned from haemocytes cDNA library by the combination of homology cloning and rapid amplification of cDNA ends (RACE). The PtPLC contained an open reading frame (ORF) of 1098 bp encoding a putative pacifastin-related precursor of 365 amino acids, a 5'-untranslated region (UTR) of 33 bp, and a 3'-UTR of 524 bp. The estimated molecular weight of mature PtPLC was 40.51 kDa and its isoelectric point was 5.04. Eight PLD domains in PtPLC shared a common characteristic of conserved array of six cysteine residues (Cys-Xaa(9-12)-Cys-Asn-Xaa-Cys-Xaa- Cys-Xaa(2-3)-Gly-Xaa(3-4)-Cys-Thr-Xaa(3)-Cys). The mRNA expression of PtPLC transcripts was highly detected in haemocytes, gill, hepatopancreas and stomach. The temporal expression levels of PtPLC transcripts in haemocytes showed different expression patterns after challenged by Gram-negative bacteria Vibrio alginolyticus, Gram-positive bacteria Micrococcus luteus and fungus Pichia pastoris. There were two peaks in the mRNA expression profile after M. luteus stimulation. And after V. alginolyticus and P. pastoris stimulation, there were three peaks in the mRNA expression profiles. These findings suggest that PtPLC is involved in the antibacterial defense mechanism of P. tritubercualtus.
Fish & Shellfish Immunology 11/2011; 32(2):331-8. · 3.32 Impact Factor
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ABSTRACT: Arginine kinase (AK) is an important phosphotransferase that plays a critical role in energy metabolism in invertebrates. In this paper, the cDNA of AK (designated as PtAK) was identified from the eyestalk cDNA library of swimming crab Portunus trituberculatus. The full-length cDNA was 1,479 bp, containing an open reading frame of 1,074 bp that coded for 357 amino acids. The estimated molecular mass of mature PtAK was 40.30 kDa and theoretical isoelectric point was 6.18. Amino acid sequence alignment showed that PtAK had very high similarity with other shrimp and crab AKs ranging from 0.876 to 0.983. The genomic DNA fragments of about 1,434 bp consisted of two exons interrupted by an intron. Totally 24 SNPs, including 17 in the coding region and seven in the non-coding region, were detected by direct sequencing of 19 genomic samples. In exon 1, the coding SNPs (cSNPs) were only found in the disease-resistant specimens. The fluorescent real-time PCR analysis revealed that the expression of PtAK was detected in all the examined tissues with the highest expression in the muscle and the lowest in the eyestalk. The expression of PtAK after Vibrio alginolyticus injection was tested in haemocytes, showing that two peak values were 5.01-fold (at 3 h) and 3.60-fold (at 24 h) compared with the control values, respectively. The results suggested that AK might play an important role in the immune response in crabs.
Molecular Biology Reports 11/2011; 39(4):4879-88. · 2.93 Impact Factor
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ABSTRACT: Genetic variation and population structure in Portunus trituberculatus along the coast of China were revealed according to 617 bp of mitochondrial DNA control region. 90 polymorphic sites defined 53 distinct haplotypes, showing a moderately high diversity among 72 individuals sampled from eight localities. Neighbor-joining tree, statistics analyses of gene flow and genetic differentiation index indicated two populations from Beihai and Laizhou had differentiated. The population from Yingkou, Dandong, Laizhou and Beihai had smaller genetic diversity compared to that from Ningbo, Lianyungang, Qingdao and Japan according to the genetic distance. And mantel test showed significant positive correlation between genetic distance and geographic distance for P. trituberculatus. TCS parsimony network suggested that all the animals sampled were probably the result of recent divergence from a common ancestral haplotype but for Laizhou population. Moreover, the haplotype distribution appeared to correlate with a recent colonization followed by localized genetic differentiation. Mismatch distribution results suggested that Ningbo, Yingkou, Qingdao, Lianyungang and Japan populations, particularly Dandong population had experienced a sudden demographic or spatial expansion. The Pleistocene glaciations might contribute to this process.
Molecular Biology Reports 05/2011; 39(2):1453-63. · 2.93 Impact Factor
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ABSTRACT: Recent studies on the mitochondrial genome have suggested that the duplications of tRNA and tandem repeats in the control region are important changes that are related to species diversity. This paper reports the study of mitogenomes from five Pampus (Perciformes, Stromateidae) species with very similar morphology. A duplicated tRNA(Met) gene in the tRNA-IQM region is present in Pampus sp. and P. punctatissimus. In the conserved sequence blocks of the control region, a duplicated CSB3 and promoter are found in Pampus sp. but are absent in P. minor. Moreover, a duplicated TAS is found in P. punctatissimus and P. chinensis. Based on the complete mitogenome sequence of Pampus sp., the first sequence reported from Stromateidae and the longest (17,694 bp) among the Perciformes mitogenomes, we conducted phylogenetic analysis to show that Stromateoidei and Scombroidei are more closely related to each other than to other Perciformes suborders. However, we reject the reciprocal monophyly of these two suborders.
Molecular Biology Reports 02/2011; 38(2):1103-14. · 2.93 Impact Factor
