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1.
BMC Biol ; 21(1): 271, 2023 11 24.
Article in English | MEDLINE | ID: mdl-38001496

ABSTRACT

BACKGROUND: Fraction of functional sequence in the human genome remains a key unresolved question in Biology and the subject of vigorous debate. While a plethora of studies have connected a significant fraction of human DNA to various biochemical processes, the classical definition of function requires evidence of effects on cellular or organismal fitness that such studies do not provide. Although multiple high-throughput reverse genetics screens have been developed to address this issue, they are limited to annotated genomic elements and suffer from non-specific effects, arguing for a strong need to develop additional functional genomics approaches. RESULTS: In this work, we established a high-throughput lentivirus-based insertional mutagenesis strategy as a forward genetics screen tool in aneuploid cells. Application of this approach to human cell lines in multiple phenotypic screens suggested the presence of many yet uncharacterized functional elements in the human genome, represented at least in part by novel exons of known and novel genes. The novel transcripts containing these exons can be massively, up to thousands-fold, induced by specific stresses, and at least some can represent bi-cistronic protein-coding mRNAs. CONCLUSIONS: Altogether, these results argue that many unannotated and non-canonical human transcripts, including those that appear as aberrant splice products, have biological relevance under specific biological conditions.


Subject(s)
DNA , Genomics , Humans , RNA, Messenger/metabolism , Exons , Genomics/methods , Mutagenesis, Insertional , Alternative Splicing
2.
Front Microbiol ; 14: 1137086, 2023.
Article in English | MEDLINE | ID: mdl-36910229

ABSTRACT

RNA viruses are the etiological agents of many infectious diseases. Since RNA viruses are error-prone during genome replication, rapid, accurate and economical whole RNA viral genome sequence determination is highly demanded. Next-generation sequencing (NGS) techniques perform whole viral genome sequencing due to their high-throughput sequencing capacity. However, the NGS techniques involve a significant burden for sample preparation. Since to generate complete viral genome coverage, genomic nucleic acid enrichment is required by reverse transcription PCR using virus-specific primers or by viral particle concentration. Furthermore, conventional NGS techniques cannot determine the 5' and 3' terminal sequences of the RNA viral genome. Therefore, the terminal sequences are determined one by one using rapid amplification of cDNA ends (RACE). However, since some RNA viruses have segmented genomes, the burden of the determination using RACE is proportional to the number of segments. To date, there is only one study attempting whole genome sequencing of multiple RNA viruses without using above mentioned methods, but the generated sequences' accuracy compared to the reference sequences was up to 97% and did not reach 100% due to the low read depth. Hence, we established novel methods, named PCR-NGS and RCA-NGS, that were optimized for an NGS machine, MinION. These methods do not require nucleic acid amplification with virus-specific PCR primers, physical viral particle enrichment, and RACE. These methods enable whole RNA viral genome sequencing by combining the following techniques: (1) removal of unwanted DNA and RNA other than the RNA viral genome by nuclease treatment; (2) the terminal of viral genome sequence determination by barcoded linkers ligation; (3) amplification of the viral genomic cDNA using ligated linker sequences-specific PCR or an isothermal DNA amplification technique, such as rolling circle amplification (RCA). The established method was evaluated using isolated RNA viruses with single-stranded, double-stranded, positive-stranded, negative-stranded, non-segmented or multi-segmented genomes. As a result, all the viral genome sequences could be determined with 100% accuracy, and these mean read depths were greater than 2,500×, at least using either of the methods. This method should allow for easy and economical determination of accurate RNA viral genomes.

3.
J Fungi (Basel) ; 10(1)2023 Dec 31.
Article in English | MEDLINE | ID: mdl-38248940

ABSTRACT

In the present study, sixteen novel RNA mycoviruses co-infecting a single strain of Rhizoctonia zeae (strain D40) were identified and molecularly characterized using metatranscriptome sequencing combined with a method for rapid amplification of cDNA ends. The fungal strain was isolated from diseased seedlings of sugar beet with damping-off symptoms. Based on genome analysis and phylogenetic analysis of amino acid sequences of RNA-dependent RNA polymerase, the sixteen mycoviruses associated with strain D40 contained three genome types with nine distinct lineages, including positive single-stranded RNA (Hypoviridae, Yadokariviridae, Botourmiaviridae, and Gammaflexiviridae), double-stranded RNA (Phlegiviridae, Megabirnaviridae, Megatotiviridae, and Yadonushiviridae), and negative single-stranded RNA (Tulasviridae), suggesting a complex composition of a mycoviral community in this single strain of R. zeae (strain D40). Full genome sequences of six novel mycoviruses and the nearly full-length sequences of the remaining ten novel mycoviruses were obtained. Furthermore, seven of these sixteen mycoviruses were confirmed to assemble virus particles present in the R. zeae strain D40. To the best of our knowledge, this is the first detailed study of mycoviruses infecting R. zeae.

4.
Leuk Res ; 123: 106952, 2022 12.
Article in English | MEDLINE | ID: mdl-36272389

ABSTRACT

The mutational status of the variable region of the immunoglobulin heavy chain gene (IGHV) is a very important biomarker for chronic lymphocytic leukemia (CLL) patients. However, the routine detection of IGHV mutational status is time-consuming and costly. Therefore, we performed 5' Rapid amplification of cDNA ends (5' RACE) in 81 CLL patients who previously underwent detection using Biomed-2. The agreement rate of these two methods was 93.8 %. Regarding the discordant cases, 5' RACE was more sensitive to identify unproductive and multiple rearrangements. Furthermore, 5' RACE can also be used to simultaneously sequence light chains. In most CLL cases, the mutational statuses of heavy and light chains are concordant, except in IGLV3-21. Most IGLV3-21 (24/25) rearrangement shared a similar LCDR3 (QVWDSSSDHPWV) and harbored a single point mutation, namely, IGLV3-21R110. Compared to mutated-CLL non IGLV3-2R110, IGLV3-21R110-CLL exhibited a shorter overall survival (OS) and time to first treatment (TTFT) (p = 0.05, p < 0.0001, respectively) even though 75 % (18/24) of these patients expressed mutated heavy chains. Altogether, IGLV3-21R110 defines a CLL subgroup with specific biological features and an unfavorable prognosis independent of the IGHV mutational status and emphasizes the important value of the light chain. This study is the first to use 5' RACE to detect the mutational status of IGH in CLL. Here, 5' RACE was a reliable and effective method to test the mutational status of heavy and light chains. In addition, 5' RACE can be combined with other assays in the NGS workflow to obtain more detailed insight into subclonal architecture and intraclonal diversity.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Genes, Immunoglobulin , Immunoglobulin Variable Region/genetics , DNA, Complementary , Genes, Immunoglobulin Heavy Chain , Mutation , Prognosis
5.
Viruses ; 14(4)2022 04 14.
Article in English | MEDLINE | ID: mdl-35458543

ABSTRACT

Six novel mycoviruses that collectively represent the mycovirome of Rhizoctonia solani anastomosis group (AG)-3 PT strain ZJ-2H, which causes potato black scurf, were identified through metatranscriptome sequencing and putatively designated as Rhizoctonia solani fusarivirus 4 [RsFV4, positive single-stranded RNA (+ssRNA)], Rhizoctonia solani fusarivirus 5 (RsFV5, +ssRNA), Rhizoctonia solani mitovirus 40 (RsMV40, +ssRNA), Rhizoctonia solani partitivirus 10 [RsPV10, double-stranded RNA (dsRNA)], Rhizoctonia solani partitivirus 11 (RsPV11, dsRNA), and Rhizoctonia solani RNA virus 11 (RsRV11, dsRNA). Whole genome sequences of RsFV4, RsMV40, RsPV10, RsPV11, and RsRV11, as well as a partial genome sequence of RsFV5, were obtained. The 3'- and 5'- untranslated regions of the five mycoviruses with complete genome sequences were folded into stable stem-loop or panhandle secondary structures. RsFV4 and RsFV5 are most closely related to Rhizoctonia solani fusarivirus 1 (RsFV1), however, the first open reading frame (ORF) of RsFV4 and RsFV5 encode a hypothetical protein that differs from the first ORF of RsFV1, which encodes a helicase. We confirmed that RsPV10 and RsPV11 assemble into the spherical virus particles (approximately 30 nm in diameter) that were extracted from strain ZJ-2H. This is the first report that +ssRNA and dsRNA viruses co-infect a single strain of R. solani AG-3 PT.


Subject(s)
Fungal Viruses , RNA Viruses , Anastomosis, Surgical , Fungal Viruses/genetics , Genome, Viral , Phylogeny , RNA Viruses/genetics , RNA, Double-Stranded/genetics , RNA, Viral/genetics , Rhizoctonia
6.
BMC Genomics ; 23(1): 163, 2022 Feb 26.
Article in English | MEDLINE | ID: mdl-35219290

ABSTRACT

BACKGROUND: Technological advancements in the era of massive parallel sequencing have enabled the functional dissection of the human transcriptome. However, 5' ends of mRNAs are significantly underrepresented in these datasets, hindering the efficient analysis of the complex human transcriptome. The implementation of the template-switching mechanism at the reverse transcription stage along with 5' rapid amplification of cDNA ends (RACE) constitutes the most prominent and efficient strategy to specify the actual 5' ends of cDNAs. In the current study, we developed a 5' RACE-seq method by coupling a custom template-switching and 5' RACE assay with targeted nanopore sequencing, to accurately unveil 5' termini of mRNA targets. RESULTS: The optimization of the described 5' RACE-seq method was accomplished using the human BCL2L12 as control gene. We unveiled that the selection of hybrid DNA/RNA template-switching oligonucleotides as well as the complete separation of the cDNA extension incubation from the template-switching process, significantly increase the overall efficiency of the downstream 5' RACE. Collectively, our results support the existence of two distinct 5' termini for BCL2L12, being in complete accordance with the results derived from both direct RNA and PCR-cDNA sequencing approaches from Oxford Nanopore Technologies. As proof of concept, we implemented the described 5' RACE-seq methodology to investigate the 5' UTRs of several kallikrein-related peptidases (KLKs) gene family members. Our results confirmed the existence of multiple annotated 5' UTRs of the human KLK gene family members, but also identified novel, previously uncharacterized ones. CONCLUSIONS: In this work we present an in-house developed 5' RACE-seq method, based on the template-switching mechanism and targeted nanopore sequencing. This approach enables the broad and in-depth study of 5' UTRs of any mRNA of interest, by offering a tremendous sequencing depth, while significantly reducing the cost-per reaction compared to commercially available kits.


Subject(s)
Nanopore Sequencing , 5' Untranslated Regions , DNA, Complementary/genetics , Humans , Muscle Proteins/genetics , Proto-Oncogene Proteins c-bcl-2/genetics , RNA, Messenger/genetics , Sequence Analysis, RNA/methods , Transcriptome
7.
Plant Divers ; 43(1): 63-70, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33778226

ABSTRACT

Establishing a transgenic plant largely relies on a selectable marker gene that can confer antibiotic or herbicide resistance to plant cells. The existence of such selectable marker genes in genetically modified foods has long been criticized. Plant cells generally exhibit too low an activity of phosphomannose isomerase (PMI) to grow with mannose as a sole carbon source. In this study, we characterized PMI from the green microalga Chlorococcum sp. and assessed its feasibility as a selectable marker for plant biotechnology. Chlorococcum sp. PMI (ChlPMI) was shown to be closely related to higher plants but more distant to bacterial counterparts. Overexpression of ChlPMI in tomato induced callus and shoot formation in media containing mannose (6 g/L) and had an average transformation rate of 3.9%. Based on this transformation system, a polycistronic gene cluster containing crtB, HpBHY, CrBKT and SlLCYB (BBBB) was co-expressed in a different tomato cultivar. Six putative transformants were achieved with a transformation rate of 1.4%, which produced significant amounts of astaxanthin due to the expression of the BBBB genes. Taken together, these findings indicate that we have established an additional tool for plant biotechnology that may be suitable for genetically modifying foods safely.

8.
Sheng Wu Gong Cheng Xue Bao ; 37(2): 635-645, 2021 Feb 25.
Article in Chinese | MEDLINE | ID: mdl-33645161

ABSTRACT

One of the distinct characters of Latrodectus tredecimguttatus is that its toxic components exist not only in the venomous glands, but also in the tissues outside the venomous glands and even in the eggs. Investigation on the toxins outside the venomous glands can deepen our understanding of spider toxins and discover new lead molecules with important application prospects. In order to explore the low-abundance proteinaceous toxins in the L. tredecimguttatus eggs, we used bioinformatic strategies to mine a gene sequence encoding a peptide toxin from the transcriptome of L. tredecimguttatus eggs, and then heterologously expressed the gene successfully with a 3'-RACE combined with nest PCR strategy. Biological activity analyses indicated that the expressed peptide toxin, named latroeggtoxin-Ⅵ (LETX-Ⅵ), could inhibit Na⁺ channel currents in ND7/23 cells and promote dopamine release from PC12 cells, without obvious toxicity against Periplaneta americana and bacteria as well as fungi including Staphylococcus aureus and Candida albicans, demonstrating that LETX-Ⅵ is a mammal-specific neurotoxin with a potential application prospect in development of the tool reagents for neurobiological study and the drugs for treating related diseases.


Subject(s)
Black Widow Spider , Spider Venoms , Animals , Arthropod Proteins/genetics , Black Widow Spider/genetics , Cloning, Molecular , Rats , Spider Venoms/genetics , Transcriptome
9.
JHEP Rep ; 3(1): 100177, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33294829

ABSTRACT

Long non-coding RNAs (lncRNAs) are important biological mediators that regulate numerous cellular processes. New experimental evidence suggests that lncRNAs play essential roles in liver development, normal liver physiology, fibrosis, and malignancy, including hepatocellular carcinoma and cholangiocarcinoma. In this review, we summarise our current understanding of the function of lncRNAs in the liver in both health and disease, as well as discuss approaches that could be used to target these non-coding transcripts for therapeutic purposes.

10.
Chinese Journal of Biotechnology ; (12): 635-645, 2021.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-878588

ABSTRACT

One of the distinct characters of Latrodectus tredecimguttatus is that its toxic components exist not only in the venomous glands, but also in the tissues outside the venomous glands and even in the eggs. Investigation on the toxins outside the venomous glands can deepen our understanding of spider toxins and discover new lead molecules with important application prospects. In order to explore the low-abundance proteinaceous toxins in the L. tredecimguttatus eggs, we used bioinformatic strategies to mine a gene sequence encoding a peptide toxin from the transcriptome of L. tredecimguttatus eggs, and then heterologously expressed the gene successfully with a 3'-RACE combined with nest PCR strategy. Biological activity analyses indicated that the expressed peptide toxin, named latroeggtoxin-Ⅵ (LETX-Ⅵ), could inhibit Na⁺ channel currents in ND7/23 cells and promote dopamine release from PC12 cells, without obvious toxicity against Periplaneta americana and bacteria as well as fungi including Staphylococcus aureus and Candida albicans, demonstrating that LETX-Ⅵ is a mammal-specific neurotoxin with a potential application prospect in development of the tool reagents for neurobiological study and the drugs for treating related diseases.


Subject(s)
Animals , Rats , Arthropod Proteins/genetics , Black Widow Spider/genetics , Cloning, Molecular , Spider Venoms/genetics , Transcriptome
11.
Methods Mol Biol ; 1933: 187-194, 2019.
Article in English | MEDLINE | ID: mdl-30945185

ABSTRACT

Long intergenic noncoding RNAs (lincRNAs), which possess diverse features such as remodeling chromatin and genome architecture, RNA stabilization, and genome architecture, are important regulatory factors in plant genomes. They serve to fine-tune the expression of neighboring genes. Here, we describe a procedure of discovery, identification, and functional characterization of plant lincRNAs after virus infection. From high-throughput RNA-Seq transcriptome analysis, the noncoding RNA transcripts with significant fold changes (upregulation or downregulation) will be discovered and identified. The lincRNA of interest will be further confirmed and validated using rapid amplification of cDNA ends (RACE). In addition, functional characterization of the lincRNA will be followed up through overexpression and knockdown strategies.


Subject(s)
Arabidopsis/genetics , Arabidopsis/virology , DNA, Intergenic/genetics , Gene Expression Regulation, Plant , Genome, Plant , RNA, Long Noncoding/genetics , RNA, Plant/genetics , Gene Expression Profiling , High-Throughput Nucleotide Sequencing , Sequence Analysis, RNA , Transcriptome
12.
J Biochem Mol Toxicol ; 33(6): e22310, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30790392

ABSTRACT

Zearalenone (ZEA) and imprinted long noncoding RNAs (lncRNAs) are both closely related to reproduction and development. However, whether they have connections in regulating reproduction and development is not clear yet. The aim of this research is to investigate their relationship. lncRNA microarray was performed to analyze differentially expressed genes, and real-time quantitative polymerase chain reaction (PCR) was used to verify the accuracy of microarray analysis. Meanwhile, the technologies of rapid amplification of cDNA ends, RNA fluorescence in situ hybridization and bioinformatics were adopted to characterize the selected lncRNA. Analysis of lncRNA microarray showed lncRNAs and messenger RNAs related to reproduction and development were significantly differently expressed, and Dio3os was probably the target lncRNA. Then, the experiment of real-time quantitative PCR verified the accuracy of microarray data. Characterization of Dio3os showed Dio3os, an antisense lncRNA with 2312 bp and 15 open reading frames, was enriched in the cytoplasm. Our findings suggest ZEA probably exerts toxic effects on reproduction and development by mediating Dio3os.


Subject(s)
Endometrium/metabolism , RNA, Antisense/biosynthesis , RNA, Long Noncoding/biosynthesis , Reproduction/drug effects , Zearalenone/toxicity , Animals , Endometrium/pathology , Female , Mice , Stromal Cells/metabolism , Stromal Cells/pathology
13.
Biochem Biophys Res Commun ; 516(3): 1046-1052, 2019 08 27.
Article in English | MEDLINE | ID: mdl-29054410

ABSTRACT

Cytochrome P450s (CYPs) play critical role in oxidative metabolism of numerous xenobiotics and endogenous compounds. The first CYP3A subfamily member in saltwater crocodile has been cloned and modelled for three-dimensional (3D) structure. The full-length cDNA was obtained employing reverse transcription polymerase chain reaction (RT-PCR) strategy and rapid amplification of cDNA ends (RACE). The cDNA sequence of 1659 nucleotides includes 132 nucleotides from 5' untranslated region (UTR), an open reading frame of 1527 nucleotides encoding 509 amino acids designated as CYP3A163. The alignment of CYP3A163 sequence with CYP3A subfamily across the lineages exhibit the loss of 1 residue in birds and 7 residues in mammals in comparison to reptiles suggesting the adaptation processes during evolution. The amino acid identity of CYP3A163 with Alligator mississippiensis CYP3A77 and Homo sapiens CYP3A4 is 91% and 62% respectively. The 3D structure of CYP3A163 modelled using human CYP3A4 structure as a template with Phyre2 software, represents high similarity with its functionally important motifs and catalytic domain. Both sequence and structure of CYP3A163 display the common and conserved features of CYP3A subfamily. Overall, this study provides primary molecular and structural data of CYP3A163 required to investigate the xenobiotic metabolism in saltwater crocodiles.


Subject(s)
Alligators and Crocodiles/genetics , Cloning, Molecular/methods , Cytochrome P-450 CYP3A/genetics , DNA, Complementary/genetics , Reptilian Proteins/genetics , Alligators and Crocodiles/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cytochrome P-450 CYP3A/chemistry , Cytochrome P-450 CYP3A/metabolism , Humans , Protein Conformation , Reptilian Proteins/chemistry , Reptilian Proteins/metabolism , Sequence Analysis, DNA , Sodium Chloride/chemistry , Substrate Specificity , Water/chemistry , Xenobiotics/metabolism
14.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-851026

ABSTRACT

Objective: To clone the full-length cDNA of jasmonate-zim-domain protein (JAZ) gene in Aquilaria sinensis to provide the basic information for further study on gene function in sesquiterpenes biosynthesis pathway. Methods: With the total RNA as template, the full-length cDNA of JAZ in A. sinensis was cloned through rapid amplification of cDNA ends (RACE) technique and reverse transcription PCR (qRT-PCR) method. The bioinformatics of the JAZ gene was analyzed as well. The expression of this gene was detected by qRT-PCR method with MeJA and mechanical wounding treatment in A. sinensis callus. Results: The full-length cDNA (1 507 bp) of JAZ gene was named AsJAZ1; GenBank registration number was KP677281. AsJAZ1 was obtained with an open reading frame (ORF) of 990 bp and encoding 330 amino acids. The relative molecular mass of AsJAZ1 calculated was 34 280, and the isoelecric point was 6.89. Real time PCR results indicated that both MeJA treatment and mechanical wounding could stimulate the increase of mRNA expression of AsJAZ1; There was a sharp rise at 0.5 h with about 27 times higher than the control (without MeJA treatment) with MeJA treatment, then dropped significantly. In mechanical wounding treatment, the highest peak presented in 2 h about 17 times compared to the control, then dropped significantly too. The expression of AsJAZ1 gene returned to be normal in 24 h. Conclusion: We have obtained the full-length cDNA sequence of AsJAZ1 gene firstly, which was extremely sensitive to wounding and responded to the early damage.

15.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-746046

ABSTRACT

Objective To obtain the full-length sequence of the vacuolar protein sorting 34 coding gene (vps34) of Sporothrix globosa (S. globosa) and to investigate the role of vps34 gene during the phase transition from mycelium to yeast in S. globosa. -ethods The 3′ end and 5′ end of the vps34 gene of S. globosa were amplified by rapid amplification of cDNA ends ( RACE ) . The obtained sequences were spliced and analyzed by bioinformatics software. Quantitative reverse transcription PCR ( qRT-PCR ) was used to analyze the expression of vps34 gene in mycelial and yeast phases. Results The vps34 gene of S. globosa was 3228 bp in length. The coding sequence was 3000 bp and encoded 999 amino acids with a mo-lecular mass of 111. 49×103 and an isoelectric point of 6. 38. It contained three domains including C2 PI3K class Ⅲ, PI3Ka Ⅲ and PI3Kc Ⅲ. The results of qRT-PCR showed that the expression of vps34 gene in yeast-phase S. globosa was higher than that in mycelial phase at 24 h (P<0. 05), and the greatest difference between them was observed at 48 h (P<0. 01). Conclusions Vps34p participates in the process of dimor-phic transformation of S. globosa. The obtainment of the full-length vps34 gene of S. globosa lays the founda-tions for further study on the function of Vps34p.

16.
Gene ; 662: 123-130, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29627524

ABSTRACT

Amanita exitialis Zhu L. Yang & T. H. Li is the species responsible for the largest number of mushroom-associated human poisonings and fatalities in South China due to its lethal cyclic peptide toxins. Prolyl oligopeptidase B (POPB) is considered a key enzyme in the production of the highly toxic cyclic peptide α-amanitin. However, the POPB gene of A. exitialis has not been studied. In the present study we cloned and sequenced the full-length A. exitialis POPB (AePOPB) gene. The aim was to verify the gene structure and functions of AePOPB. The full-length sequence of AePOPB is 3144 bp, including 18 exons encoding 730 aa, and the advanced structure is very similar to that of the previously reported POPB in Galerina marginata (GmPOPB). The amino acid sequence of AePOPB is highly homologous with those from other amanitin-producing lethal mushrooms, implying that AePOPB may have a similar role in the biosynthesis of cyclic peptide toxins. Expression levels of AePOPB were detectable in all parts and developmental stages of the fruiting bodies, and AePOPB was expressed more strongly at early development stages (early and late elongation stages). At early and late elongation stages, the expression peaks occurred in the stipe, whereas at early and late mature stages, the expression peaks occurred in the pileus. The expression patterns of AePOPB in different stages and different parts of the fruiting bodies were highly consistent with those of Aeα-AMA, which is required for α-amanitin accumulation. These results indicate that AePOPB should be involved in the α-amanitin biosynthesis in A. exitialis.


Subject(s)
Alpha-Amanitin/genetics , Amanita/genetics , Serine Endopeptidases/genetics , Alpha-Amanitin/biosynthesis , Alpha-Amanitin/metabolism , Amanitins/genetics , Amanitins/metabolism , Amino Acid Sequence , Base Sequence/genetics , Cloning, Molecular/methods , Fruiting Bodies, Fungal/genetics , Gene Expression Regulation, Fungal/genetics , Peptides, Cyclic/genetics , Phylogeny , Prolyl Oligopeptidases , Serine Endopeptidases/metabolism , Toxins, Biological/metabolism
17.
Biosci Biotechnol Biochem ; 82(7): 1090-1100, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29621939

ABSTRACT

A cDNA of putative chitinase from Euglena gracilis, designated EgChiA, encoded 960 amino acid residues, which is arranged from N-terminus in the order of signal peptide, glycoside hydrolase family 18 (GH18) domain, carbohydrate binding module family 18 (CBM18) domain, GH18 domain, CBM18 domain, and transmembrane helix. It is likely that EgChiA is anchored on the cell surface. The recombinant second GH18 domain of EgChiA, designated as CatD2, displayed optimal catalytic activity at pH 3.0 and 50 °C. The lower the polymerization degree of the chitin oligosaccharides [(GlcNAc)4-6] used as the substrates, the higher was the rate of degradation by CatD2. CatD2 degraded chitin nanofibers as an insoluble substrate, and it produced only (GlcNAc)2 and GlcNAc. Therefore, we speculated that EgChiA localizes to the cell surface of E. gracilis and is involved in degradation of chitin polymers into (GlcNAc)2 or GlcNAc, which are easily taken up by the cells.


Subject(s)
Chitinases/metabolism , DNA, Complementary/genetics , Euglena gracilis/enzymology , Acetylglucosamine/metabolism , Amino Acid Sequence , Antifungal Agents/pharmacology , Base Sequence , Catalysis , Catalytic Domain , Chitin/metabolism , Chitinases/genetics , Chitinases/pharmacology , Chromatography, High Pressure Liquid , Cloning, Molecular , Electrophoresis, Polyacrylamide Gel , Escherichia coli/genetics , Hydrogen-Ion Concentration , Nanofibers , Oligosaccharides/metabolism , Polymerization , Proteolysis , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Substrate Specificity , Temperature
18.
Biochem Biophys Rep ; 13: 116-122, 2018 03.
Article in English | MEDLINE | ID: mdl-29556566

ABSTRACT

Programmed death-1 (PD-1), upon engagement by its ligands, programmed death ligand-1 (PD-L1) and programmed death ligand-2 (PD-L2), provides signals that attenuate adaptive immune responses. Here we describe the identification of the Pekin duck PD-L2 (duPD-L2) and its gene structure. The duPD-L2 cDNA encodes a 321 amino acid protein that has an amino acid identity of 76% and 35% with chicken and human PD-L2, respectively. Mapping of the duPD-L2 cDNA with duck genomic sequences revealed an exonic structure similar to that of the human Pdcd1lg2 gene. Homology modelling of the duPD-L2 protein was compatible with the murine PD-L2 ectodomain structure. Residues known to be important for PD-1 receptor binding of murine PD-L2 were mostly conserved in duPD-L2 within sheets A and G and partially conserved within sheets C and F. DuPD-L2 mRNA was constitutively expressed in all tissues examined with highest expression levels in lung, spleen, cloaca, bursa, cecal tonsil, duodenum and very low levels of expression in muscle, kidney and brain. Lipopolysaccharide treatment of adherent duck PBMC upregulated duPD-L2 mRNA expression. Our work shows evolutionary conservation of the PD-L2 ectodomain structure and residues important for PD-1 binding in vertebrates including fish. The information provided will be useful for further investigation of the role of duPD-L2 in the regulation of duck adaptive immunity and exploration of PD-1-targeted immunotherapies in the duck hepatitis B infection model.

19.
Biosci Biotechnol Biochem ; 82(2): 258-267, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29318910

ABSTRACT

We isolated a novel lectin (Artocarpus nitidus subsp. lingnanensis lectin, ALL) from Artocarpus nitidus subsp. lingnanensis and showed its mitogenic activities. In this study, we determined the amino acid sequence of ALL by cDNA sequencing. ALL cDNA (933 bp) contains a 657-bp open reading frame (ORF), which encodes a protein with 218 amino acids. ALL shares high sequence similarities with Jacalin and Morniga G and belongs to jacalin-related lectin family. We also examined the antitumor activity of ALL using Raji, a human B-lymphoma cell line. ALL exhibits a strong binding affinity to cell membrane, which can be effectively inhibited by N-acetyl-D-galactosamine (GalNAc). ALL inhibits Raji cell proliferation in a time- and dose-dependent manner through apoptosis, evidenced by morphological changes, phosphatidylserine externalization, poly ADP-ribose polymerase (PARP) cleavage, Bcl-2 down-regulation, and caspase-3 activation. We further showed that the activation of p38 mitogen-activated protein kinase (MAPK) signaling pathways is required for the pro-apoptotic activity of ALL.


Subject(s)
Apoptosis/genetics , Artocarpus/genetics , Lymphoma, B-Cell/pathology , Plant Lectins/genetics , Amino Acid Sequence , Base Sequence , Cell Line, Tumor , Cloning, Molecular , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Phosphorylation/genetics , Plant Lectins/chemistry , p38 Mitogen-Activated Protein Kinases/metabolism
20.
Methods Mol Biol ; 1640: 23-37, 2017.
Article in English | MEDLINE | ID: mdl-28608332

ABSTRACT

Uridylation (3' untemplated uridine addition) provides a mechanism to trigger the degradation of miRNAs and the 5' cleavage products (5' CP) that are produced from miRNA-directed ARGONAUTE (AGO) cleavage of target RNAs. We have recently shown that HEN1 SUPPRESSOR 1 (HESO1), a terminal uridylyltransferase, and its homolog UTP:RNA uridylyltransferase 1 (URT1) catalyze the uridylation of miRNAs and 5' CPs within the AGO complex in higher plants. In this chapter, we describe detailed protocols for analyzing 3' end uridylation of both AGO-bound miRNAs and 5' CP.


Subject(s)
Argonaute Proteins/metabolism , MicroRNAs/metabolism , Nicotiana/metabolism , Plant Proteins/metabolism , RNA, Plant/metabolism , Uridine/metabolism , Argonaute Proteins/genetics , Cloning, Molecular/methods , DNA, Complementary/genetics , Gene Expression , MicroRNAs/chemistry , MicroRNAs/genetics , Nucleic Acid Amplification Techniques/methods , Plant Proteins/genetics , Protein Binding , RNA Stability , RNA, Plant/chemistry , RNA, Plant/genetics , Nicotiana/chemistry , Nicotiana/genetics , Uridine/analysis , Uridine/genetics
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