A xylanolytic microorganism, strain DY-7, was isolated from the gut of the mole cricket, Gryllotalpa orientalis. The result of phylogenetic analysis based on its 16S rDNA sequence revealed that the isolate was a Gram-positive bacterium belonging to the genus Streptomyces. The cloned gene (1350-bp) encoding a GH family 10 β -1,4-xylanase (XylA) from Streptomyces sp. strain DY-7 was overexpressed in Escherichia coli BL21 and its gene products were characterized. The hydrolysis activities of rXylA and rXylAΔCBD II against xylosidic materials were maximum at pH 5.5 and 65oC. However, deletion of CBD II in the C-terminus region of XylA significantly increased the thermal stability of the enzyme at high temperatures above 50oC. The xylanolytic activity of rXylA was slightly enhanced in the presence of 1 mM Mn2+ and 5 mM sodium azide but it was completely inactivated by 1 mM Hg2+ and 5 mM N-bromosuccinimide. rXylA was capable of efficiently decomposing various xylosidic compounds, PNP-cellobioside, and PNP-xylopyranoside, whereas other hexose-based compounds were insensitive to the enzyme. The specific activities of rXylA toward oat spelts xylan and PNP-cellobioside were 649.8 U/mg and 328.1 U/mg, respectively. Enzymatic degradation of birchwood xylan and xylooligosaccharides (xylotriose to xylohexaose) resulted in the production of xylobiose (>75%) as the main hydrolysis product together with a small amount (4%<) of xylose as the final hydrolysis product.
A xylan-decomposing Gram-positive bacterium, Cellulosimicrobium cellulans DY-8, was isolated from the gut of a wood-feeding longicorn beetle, Moechotypa diphysis. To amplify a partial fragment of the GH 10 β-1,4- xylanase (XylC) gene of strain DY-8, two degenerated oligonucleotide primers were designed based on strictly conserved regions (WDVVNE and ITELLDV) in the GH family 10 xylanolytic enzymes. The full gene (1488-bp) of XylC, which was predicted to encode a protein consisting of 495 amino acids with a molecular mass of 52.0 kDa and a calculated pI of 6.49, was cloned by repeated DNA walking and nested PCR protocols. The results of a protein blast survey showed that XylC was a β -1,4-xylanase comprised of an N-terminal catalytic GH10 domain (from Ser48 to Leu338) and a C-terminal RICIN domain (from Tyr359 to Leu492). This overall structure of XylC was 57% identical to that of Actinoplanes sp. SE50/110 β -1,4-xylanase (Accession number: YP_006265966), which has not yet been biochemically characterized.
Sperm cell development in spider species undergoes in testicular cyst, containing certain number of cells per cyst. As a germ cell matures through entire stages of spermatogenesis, testicular cysts rupture and produced spermatozoa are transferred in a form of cleistosperm. When mature spermatozoa pass through deferent duct, it is known that various types of seminal secretions are released into the lumen to provide auxillary functions to the mature sperms – such as nutrition, protection, or sperm release inside the female body. However, a peculiar type of seminal secretion was observed in this study. In the lumen of deferent duct, encapsulated seminal secretions are observed along with coiled sperm cells. Since the capsule is quite thick – as thick as the one of mature sperm cell, it is thought that the secretion capsule would be transferred as well along with the sperm cells into the spermathecae probably activiating sperm cells through decapsulation. Also, this study revealed that sperm storage in deferent duct occurs in droplet-by-droplet basis; which suggests possible sperm inducing mechanism. Since spider uses pedipalps in copulation to transfer its sperm cells, spider has to fill it accordingly. In other words, stored sperms in deferent duct are released in a droplet at once.
In animals, structural coloration is the production of color by microscopically structured surfaces of many birds as well as many butterfly wings and beetles wing cases. This structural coloration is caused by interference effects rather than by pigments. It has been known that the colors are produced when a material is scored with fine parallel lines, formed of one or more parallel thin layers, or otherwise composed of microstructures on the scale of the colour’s wavelength. Current research is performed using light and scanning electron microscopes to examine the fine structural characteristics of scales in the three species of iridescent butterflies Papilio maackii, Charaxes tiridates and Anaea glaucone. It has been revealed that the structural coloration of these butterflies is responsible for the blues and greens of the scales of wings. In addition, the reflected color depends on the viewing angle, which in turn controls the apparent spacing of the structures responsible for specific color patterns of the wing scales.
Ips acuminatus is a minute bark beetle found in forest and can cause economic damage to pine and spruce trees. This beetle has well developed sensory system respond to both of visual and chemical stimuli. Both sexes have a pair of faceted compound eyes and another pair of knobbed antennae, work together to collect vital information. The antennae look similar in both sexes and consist of scape, pedicel, and segmented flagellum. The pedicel is the first segment by which the antenna is attached to the head and the scape is set in a membranous socket and surrounded by the antennal sclerite on which a single articulation occurs. The beetle’s antennae enlarge abruptly at the last segment of a flagellum giving the antenna a knobbed appearance. There are a number of sensory receptors, including olfactory and mechanical receptors. Here, the fine structural characteristics of the antennal sensory organs in male and female bark beetle Ips acuminatus (Coleoptera: Curculionidae: Scolytinae) were analysed with field emission scanning electron microscopy (FESEM).
Male crickets (Order Orthoptera), producing sound for courting females and threatening other males, were chosen to perform researches for the better understanding of the microstructures of sound producing organs. It is known that cricket only makes sound for mating-related events. In this research, two patterns out chirping patterns were observed and analyzed. Each chirp was made of several nodes of waves, each node indicates a movement of wings – friction caused by file and plectrum located on wings. Although both wings possess file and plectrum, only the file on right wing and plectrum on left wing are used to produce sound. Each file consists of 126 teeth, where plectrum gets hooked. The teeth located on file have consistent gap between each other, proportional to the wave nodes acquired – except that the gap in the second region among equally divided six regions were shorter. In case of the usage of file, a cricket mostly uses second region to fifth region, since the teeth in first and sixth region are smaller. Since most of the researches made are mainly focused on the correlation between sound production and behavioral pattern, the current research project aims to reveal and provide thorough understanding on the sound producing organs of cricket, to suggest possible biomimetic applications in our daily lives.
We have identified novel ricin-type (R-type) lectin by sequencing of random clones from cDNA library of the coleopteran beetle, T.molitor. The cDNA sequence is comprised of 495 bp encoding a protein of 164 amino acid residues and shows 49% identity with galectin of Tribolium castaneum. Bioinformatics analysis shows that the amino acid residues from 35 to 162 belong to ricin-type β-trefoil structure. The transcript was significantly upregulated after early hours of injection with peptidoglycans derived from Gram (+) and Gram (-) bacteria, beta-1, 3 glucan from fungi and an intracellular pathogen, L. monocytogenes suggesting putative function in innate immunity.
Apolipophorin III (apoLp-III) is a well-known hemolymph protein having a functional role in lipid transport and immune response of insects. We cloned full-length cDNA encoding putative apoLp-III from larvae of the coleopteran beetle, Tenebrio molitor (TmapoLp-III), by identification of clones corresponding to the partial sequence of TmapoLp-III, subsequently followed with full length sequencing by a clone-by-clone primer walking method. The complete cDNA consists of 890 nucleotides, including an ORF encoding 196 amino acid residues. Excluding a putative signal peptide of the first 20 amino acid residues, the 176-residue mature apoLp-III has a calculated molecular mass of 19,146 Da. Genomic sequence analysis with respect to its cDNA showed that TmapoLp-III was organized into four exons interrupted by three introns. Several immune-related transcription factor binding sites were discovered in the putative 5’-flanking region. BLAST and phylogenetic analysis reveals that TmapoLp-III has high sequence identity (88%) with Tribolium castaneum apoLp-III but shares little sequence homologies (<26%) with other apoLp-IIIs. Homology modeling of Tm apoLp-III shows a bundle of five amphipathic helices, including a short helix 3’. The ‘helix-short helix-helix’ motif was predicted to be implicated in lipid binding interactions, through reversible conformational changes and accommodating the hydrophobic residues to the exterior for stability. Highest level of TmapoLp-III mRNA was detected at late pupal stages, albeit it is expressed in the larval and adult stages at lower levels. The tissue specific expression of the transcripts showed significantly higher numbers in larval fat body and adult integument. In addition, TmapoLp-III mRNA was found to be highly up-regulated in late stages of L. monocytogenes or E. coli challenge. These results indicate that TmapoLp-III may play an important role in innate immune responses against bacterial pathogens in T. molitor.
CD63, a member of tetraspanin membrane protein family, plays pivotal role in cell growth, motility, signal transduction, host-pathogen interactions and cancer. In this work, the cDNA encoding CD63 homologue (TmCD63) was cloned from larvae of coleopteran beetle, Tenebrio molitor. The cDNA is comprised of an open reading frame of 705 bp, encoding putative protein of 235 amino acid residues. In silico analysis shows that the protein has four putative transmembrane domains and one large extracellular loop. The characteristic ‘Cys-Cys-Gly’ motif and ‘Cys188’ residues are highly conserved in the large extracellular loop. Phylogenetic analysis of TmCD63 revealed that they belong to the insect cluster with 50-56% identity. Analysis of spatial expression patterns demonstrated that TmCD63 mRNA is mainly expressed in gut and Malphigian tubules of larvae and the testis of the adult. Developmental expression patterns of CD63 mRNA showed that TmCD63 transcripts are detected in late larval, pupal and adult stages. Interestingly, TmCD63 transcript was upregulated the maximum 4.5 fold in response to DAP-type peptidoglycan during the first 6 h, although other immune elicitors also made significant increase in the transcript level at later time-points. These results suggest that CD63 might contribute to T. molitor immune response against various microbial pathogens.
We present the nearly complete mitogenome sequences of the garden chafer, Polyphylla laticollis manchurica, which is listed as an endangered species in Korea. The P. l. manchurica mitogenome, which includes unfinished whole A+T-rich region and a partial srRNA was 14,473-bp long, possessing typical sets of genes (13 PCGs, 22 tRNA genes, and 2 rRNA genes). Gene arrangement of the P. l. manchurica mitogenome was identical to the common one found in the majority of insects. The 5 bp-long motif sequence (TAGTA) that has been suggested to be the possible binding site for the transcription termination peptide for the major-strand was also found in the P. l. manchurica mitogenome between tRNASer(UCN) and ND1. As has been previously determined, the high A/T content was unanimously observed in P. l. manchurica in terms of A/T bias in the third codon position (73.5%) compared with the first (66.4%) and second codon position (66.2%), and a high frequency of A/T-containing codons (a total of 28.22% for TTA, ATT, TTT, and ATA). The PCGs encoded in major-strands are slightly T-skewed, whereas those of the minor-strand are A-skewed, indicating strand asymmetry in nucleotide composition in the Coleoptera including P. l. manchurica.
Serine protease는 병원체의 표면 melanization, hemolymph coagulation, antimicrobial peptide synthesis 등을 통해 여러 무척추동물의 방어기작을 조절하는것으로 알려 져 있다. 곤충의 경우 Tribolium을 대상으로 이와 같은 연구가 이루어져 왔지만, 혈 액의 량이 그리 많지 않아 연구자들은 최근 갈색거저리(Tenebrio)를 이용하기 시작 하였다. 하지만 아직 유전체(자) 서열정보가 충분하지 않은 상황이다. 본 연구에서 는 이러한 갈색거저리 유충을 이용하여 세포벽이 없으며 사람에서 pneumonia나 다른 호흡기 질환을 일으키는 mycoplasma 와 유사한 acholeplasma lysate를 처리 한 후 접종 전과 후의 전사체의 비교를 통하여 무척추 동물에서의 선천성 면역 관련 유전자들을 동정하고자 하였다. Acholeplasma lysate를 처리하기 전과 후의 각 샘 플들로부터 cDNA library를 구축한 후 random sequencing 을 통해 염기서열을 분 석하였고, 얻어진 서열들로부터 NCBI nr 데이터베이스에 Blastx 분석을 하여 획득 한 서열들을 comparative transcriptomic 방법을 이용하여 분석한 결과, 여러 종류 의 Serine protease 관련 유전자들이 동정되었다. Serine protease (XP_970766.1)의 경우에는 acholeplasma를 처리한 샘플에서 2배 정도 발현이 증가하였고, serine protease P66 (EFA09207.1)의 경우 증감의 변화는 보이지 않았다. 또한 serine protease P146 (EFA04636.1), serine protease H1 (EEZ99180.1) 등의 유전자들도 동정되어 연구하고 있다.
Toll–interleukin 1 receptor (TIR) superfamily는 intracellular TIR domain에 존 재하며, proinflammatory cytokines을 생산하는 transcription factor NF-κB의 활성 화에 의해 선천성 면역을 개시한다. 본 연구에서는 갈색거저리 유충을 이용하여 Mycoplasma genus와 유사한 acholeplasma lysate를 접종하여 비교 유전체학적 방 법을 통하여 갈색거저리에서 면역반응에 관여하는 t1/st2 receptor binding protein 을 동정하였으며, 그 구조 분석을 위한 기초 데이터를 확보하고자 하였다. IL1RL1 (Interleukin 1 receptor-like 1) gene는 Toll-like receptor superfamily로써 사람에서 발견되며 ST2는 Toll-interleukin 1 receptor family의 member이자 endotoxin tolerance 유지에 중요한 역할을 하는 것으로 알려졌다. 갈색거저리 유충에 acholeplasma lysate를 처리하기 전과 후의 각 샘플들로부터 cDNA library를 구축 한 후 random sequencing 을 통해 분석되어진 서열들 중 증감하는 유전자들을 동정 하였고, 그 중 acholeplasma 처리 후 약 4배 정도 발현이 증가한 t1/st2 receptor binding protein 의 서열을 추출한 후 단백질의 2차 구조를 예측한 결과 alpha helix 구조는 서열상에서 8영역으로 예측되었으며 beta sheet 구조는 서열상에서 1영역 에서 존재하고 있어 후속연구를 진행하고 있다.
Tenebrio 모델은 Tribolium과 비교하여 실험실에서 배양 및 조작하기가 쉬운 생물 종이다. 하지만 현재까지는 해독되어진 유전체 정보가 그리 많지 않다. Mycoplasma genus는 세포벽이 없으며 사람에서 pneumonia 나 다른 호흡기 질환을 일으키는 박 테리아로 본 연구에서는 갈색거저리 유충을 이용하여 Mycoplasma genus와 유사 한 acholeplasma lysate를 처리하여 접종 전과 후의 비교 전사체학적 방법을 통하여 선천성 면역 관련 유전자들을 동정하고 기능 분석을 위한 기초 데이터를 확보 하고 자 하였다. 갈색거저리 유충에 acholeplasma lysate를 처리하기 전과 후의 각 샘플 들로부터 cDNA library를 구축한 후 random sequencing 을 통해 해독 되어진 염기 서열들을 비교 분석 하였다. 얻어진 서열들로부터 NCBI nr 데이터베이스에 Blastx 분석을 하여 획득한 서열들을 생물정보학적 방법을 이용하여 비교한 결과, 곤충의 선천성면역(innate Immunity)에 중요한 것으로 알려진 serpin 관련 유전자들이 약 5종류 동정되었다. Serpin (XP_974209.1) 의 경우 acholeplasma에 처리하여 전과 후 비교하였을 때, 약 3배 정도 증가를 나타내었고, serpin 6 (XP_972660.1)의 경우 에는 acholeplasma를 처리한 샘플에서만 동정되었다. 또한 serpin 3a (XP_969874.1), serpin 1(BAI59109.1), serpin 40(BAI59106.1) 등의 유전자들도 동정되었다. 추후 이러한 유전자들을 대상으로 한 기능연구를 통하여 보다 구체적인 면역기능을 구 명하고자 한다.
Most traditional genome sequencing projects involving infectious viruses include culturing and purification of the virus. This can present difficulties as an analysis of multiple populations from multiple locations may be required to acquire sufficient amount of high-quality DNA for sequence analysis. The electrophoretic method provides a strategy whereby the genomic DNA sequences of the Korean isolate of Pieris rapae granulovirus (PiraGV-K) were analyzed by purifying it from host DNA by pulsed-field gel electrophoresis, thus simplifying sampling and labor time. The genomic DNA of infected P. rapae was embedded in agarose plugs, digested with a restriction nuclease and methylase, and pulsed-field gel electrophoresis (PFGE) was used to separate PiraGV-K DNA from the DNA of P. rapae, followed by mapping of fosmid clones of the separated viral DNA. The double-stranded circular genome of PiraGV-K encodes 120 open reading frames (ORFs), covering 92% of the sequenced genome. BLAST and ORF arrangement showed the presence of 78 homologs to other genes in the database. The mean overall amino acid identity of PiraGV-K ORFs was highest with the Chinese isolate of PiraGV (~99%), followed up with Choristoneura occidentalis ORFs at 58%. PiraGV-K ORFs were grouped, according to function, into 10 genes involved in transcription, 11 involved in replication, 25 structural protein genes, and 15 auxiliary genes. Genes for Chitinase (ORF 10) and cathepsin (ORF11), involved in the liquefaction of the host, were found in the genome. The recovery of PiraGV-K DNA genome by pulse-field electrophoretic separation from host genomic DNA had several advantages, compared with its isolation from particles harvested as virions or inclusions from the P. rapae host. We have sequenced and analyzed the 108,658 bp PiraGV-K genome purified by the pulsed field electrophoretic method. The method appears to be applicable to the analysis of genomes of large viruses. The chitinase, identified by PiraGV-K genome sequence, was functionally characterized by quantitative PCR, Western blot analysis, immunohistochemistry and transmission electron microscopy.
Glyphodes quadrimaculalis (Lepidoptera: Crambidae) feed on a root tuber of Cynanchum wilfordii (Asclepiadaceae) that is one of the most famous traditional medicines in Korea. The genus Glyphodes includes ~130 species distributed worldwide, so the complete mitochondrial genome (mitogenome) would be helpful for bio-identification, biogeographic studies, and multigene-based phylogeny. The 15,255-bp long G. quadrimaculalis genome comprises 37 typical genes and one large non-coding region, with the typical arrangement found in Lepidoptera. Of the 13 protein coding genes (PCGs), 12 begin with typical start codons found in insect mitochondrial PCGs, but the COI gene starts with atypical CGA. One of the noteworthy features of the genome includes the presence of a 51-bp long non-coding space sequence located between tRNAGln and ND2 that reveals high sequence homology (71.4%) to the neighboring ND2 gene, indicating the origin of the region by partial duplication of the ND2 gene.
Peptidoglycan recognition proteins (PGRPs) are family of innate immune molecules that recognize bacterial peptidoglycan. PGRP-LE, a member of the PGRP family, selectively binds to diaminopimelic acid (DAP)-type peptidoglycan to activate both the immune deficiency (IMD) and proPhenoloxidase (proPO) pathways in insects. A PGRP-LE-dependent induction of autophagy to control Listeria monocytogenes has also been reported. We identified and partially characterized a novel PGRP-LE homologue, from Tenebrio molitor and analyzed its functional role in the survival of the insect against infection by a DAP-type PGN containing intracellular pathogen, L. monocytogenes. The cDNA is comprised of an open reading frame (ORF) of 990 bp and encodes a polypeptide of 329 residues. TmPGRP-LE contains one PGRP domain, but lacks critical residues for amidase activity. Quantitative RT-PCR analysis showed a broad constitutive expression of the transcript at various stages of development spanning from larva to adult. RNAi mediated knockdown of the transcripts followed by a challenge with L. monocytogenes showed a significant reduction in survival rate of the larvae, suggesting a putative role of TmPGRP-LE in sensing and control of L. monocytogenes infections in T. molitor. These results implicate PGRP-LE as a defense protein necessary for survival of T. molitor against infection by L. monocytogenes.
We newly sequenced mitochondrial genomes of Spodoptera litura and Cnaphalocrocis medinalis (Lepidoptera) to obtain further insight into mitochondrial genome evolution and investigated the influence of optimal strategies on phylogenetic reconstruction of Lepidoptera. Estimation of p-distances of each mitochondrial gene for available taxonomic levels has shown the highest value in ND6, whereas the lowest values in COI and COII at the nucleotide level, suggesting different utility of each gene for different hierarchical group when individual genes are utilized for phylogenetic analysis. Phylogenetic analyses mainly yielded the relationships (((((Bombycoidea + Geometroidea) + Noctuoidea) + Pyraloidea) + Papilionoidea) + Tortricoidea), evidencing the polyphyly of Macrolepidoptera. The tests of optimality strategies, such as exclusion of third codon positions, inclusion of rRNA and tRNA genes, data partitioning, RY recoding approach, and recoding nucleotides into amino acids suggested that the majority of the strategies did not substantially alter phylogenetic topologies or nodal supports, except for some familial relationship only in the amino acid dataset.
Up to now the complete mitochondrial genome (mitogenome) sequences of only three species of clitellate have been available. We have determined the complete mitogenome sequences of the elusive Burmese giant earthworm Tonoscolex birmanicus (Clitellata: Megascolecidae), which is endemic to Myanmar. The 15,170-bp long genome contains the 37 genes typical of metazoan mitogenomes [13 protein-coding genes (PCG), two rRNA genes and 22 tRNA genes] and one major non-coding region. All of the 37 genes are transcribed from the same DNA strand. The arrangement of the T. birmanicus mitogenome is identical to that of two within-ordinal species Lumbricus terrestris and Perionyx excavates. All 13 PCGs start with the ATG. For the stop codon, only six PCGs end with the TAA, whereas the remaining ones ends with the incomplete stop codon, T. Genes overlap in a total of 14 bp in five locations, and harbor a total of 16 bp of intergenic spacer sequences in nine locations.
Colorectal cancer is the third most commonly diagnosed cancer in the world, nearly all patients diagnosed with this cancer die from it. Antibodies are glycoprotein molecules, which can efficiently recognize and eliminate specific pathogenic and disease antigens. Antibody researches for the last several decades have demonstrated the potential of therapeutic antibodies to fight cancer. Monoclonal antibody (mAb) CO17-1A recognizes the tumor-associated antigen GA733-2, a cell surface glycoprotein highly expressed in colorectal carcinoma cell, which is applicable for preventing and curing colorectal cancer. We have currently established baculovirus insect cell expression system to produce anti-colorectal cancer mAb CO17-1A. In this study, mAb CO17-1A was expressed in the transgenic insect cell line SWT4, which has humanized glycosylation processing pathway. Immunoblot confirmed that mAb CO17-1A properly expressed in SWT4. mAb CO17-1A was purified using protein G affinity column. In addition, Maldi-TOF verified that the mAb fused to KDEL, ER retention signal had high mannose type of glycan structure whereas the mAb without KDEL had partially humanized glycan structure. These results suggest that the insect cell expression system with the SWT4 possibly can be used as a useful alternative way to produce full-size mAb with humanized glycan structures for cancer immunotherapy.
The antigen GA733 is a cell-surface highly expressed glycoprotein on most human colorectal carcinomas. GA733 can be characterized as a cancer vaccine. In this study, GA733 was fused to the human immunoglobulin IgG Fc fragment to become recombinant gene GA733-Fc. Based on this, 4 recombinant genes were constructed as follows: GA733-Fc with signal peptide sequence and fusion of ER retention sequence (KDEL) (spGA733-FcK), GA733-Fc with signal sequence (spGA733-Fc), GA733-Fc fused to ER retention sequence (GA733-FcK) without signal peptide and GA733-Fc without signal peptide. Baculovirus-insect cell expression system is widely used for the high level production of recombinant proteins especially for glycoproteins. Constructed 4 recombinant genes were cloned to baculovirus express vectors. DH10Bac E.coli.-mediated transformation was used to generate recombinant bacmid DNA. Recombinant DNA was confirmed by PCR. Insect cell was transfected by bacmid to produce the recombinant baculovirus infects insect cell to produce recombinant protein. Western blot and sandwich ELISA showed the expression of recombinant proteins. Each cell lines (sf9 and HighFive) differed in recombinant proteins production level and protein secretion capability. N-Glycosylation analysis showed the function of signal peptide and ER retention sequence (KDEL). Taken together, baculovirus-insect cell system can be used to express recombinant GA733-Fc glycoproteins.