Cinnamoyl-CoA reductase (CCR) is responsible for the first committed reaction in monolignol biosynthesis, which diverts phenylpropanoid-derived metabolites into the biosynthesis of lignin. To gain a better understandi...Cinnamoyl-CoA reductase (CCR) is responsible for the first committed reaction in monolignol biosynthesis, which diverts phenylpropanoid-derived metabolites into the biosynthesis of lignin. To gain a better understanding of the lion biosynthesis in wheat development, two cDNAs encoding CCR were identified from wheat (Triticum aestivum L. cv. H4564). DNA sequence analyses indicated that the two cDNAs represent two classes of CCR. RT-PCR and Northern blot hybridization demonstrated that one of them, W-cr6, was expressed actively in stem and leaf tissue, the other one, W-cr19, was expressed in root and stem tissue. The results suggested that there are at least two genes encoded for CCR existing in wheat genome.展开更多
The nucleotide sequences of the open reading frames of cDNAs for selenoprotein W from skeletal muscle of rat, mouse, sheep, rhesus monkey and human are reported. Theoretical translation of the coding sequences indicat...The nucleotide sequences of the open reading frames of cDNAs for selenoprotein W from skeletal muscle of rat, mouse, sheep, rhesus monkey and human are reported. Theoretical translation of the coding sequences indicated highly similar proteins of 88 (mouse and rat) or 87 (human, monkey and sheep) amino acids. In 73 of 88 positions the specified amino acids are identical for all five proteins. TGA encoding selenocysteine is the 13th codon of all the cDNAs. The rnouse, rat and sheep open reading frames terminate with TGA but the human and rhesus monkey coding regions terminate with TAA. The encoded amino acid sequences are identical for the rat and mouse proteins, and for the human and monkey proteins. The similarity of the cDNAs continues in the 3' noncoding regions through the putative selenocysteine insertion sequence (SEClS) elements which are required for correct interpretation of the selenocysteine codon. The region between the SECIS elements and the polyadenylation signals showed much lower similarity. The cloned rat gene for selenoprotein W is 5000 bases long,with the 663 bases of the cDNA in six exons. The transcription start site was identified by nuclease protection assay to be 16 bases upstream of the longest cDNA clone. A canonical TATA box occurs 150 bases upstream, but the assay did not indicate the presence of longer mRNAs展开更多
Total mRNA was extracted from a venom gland of snake Daboia russellii siamensis following the manufacturer＇s protocol of the PolyATtract System 1000 kit purchased from Promega Biotech. cDNAs encoding C-type lectins w...Total mRNA was extracted from a venom gland of snake Daboia russellii siamensis following the manufacturer＇s protocol of the PolyATtract System 1000 kit purchased from Promega Biotech. cDNAs encoding C-type lectins were amplified by RT-PCR and subcloned into a pMD18-T vector. Fourteen positive clones were selected for nucleotide sequencing and seven cDNAs encoding various snake venom C-type lectin-like protein precursors, designated as DRS-L1, DRS-L2, DRS-L3, DRS-L4 DRS-L5, DRS-L6 and DRS-L7, were obtained. Amino acid sequences of these proteins were deduced and each contains a carbohydrate recognition domain. Of all the deduced protein sequences, only DRS-L1 seemed to represent a closer sequence similarity to α subunits of other known snake venom C-type lectin-like proteins using the BLAST program. Homology comparison combined with analysis of cysteine position indicate that DRS-L1 and DRS-L2 are probably the light chain LC2 and LC1 of factor X activator from Daboia russellii siamensis venom, respectively. DRS-L3 and DRS-L4 might be the β subunits of higher molecular weight C-type lectin-like proteins while DRS-L5 and DRS-L6 might be β subunits of lower molecular weight C-type lectin-like proteins. DRS-L7 might be the β subunit of a platelet membrane glycoprotein Ib-binding protein similar to echicetin.展开更多
Heavy metal contamination of soil has become a major environmental concern worldwide over the past several decades,the exploitation and application of heavy metal hyperaccumulating plants will defend the safety of foo...Heavy metal contamination of soil has become a major environmental concern worldwide over the past several decades,the exploitation and application of heavy metal hyperaccumulating plants will defend the safety of food and environment on which human life relied,whereas using natural hyperaccumulators is insufficient,due展开更多
<abstract>Aim: Identification of the rodent counterparts of human and canine epididymal cDNAs HE3, HE4 and Ce8/Ly6G5C by sequence homology and analysis of their expression patterns and regulation level in the ra...<abstract>Aim: Identification of the rodent counterparts of human and canine epididymal cDNAs HE3, HE4 and Ce8/Ly6G5C by sequence homology and analysis of their expression patterns and regulation level in the rat. Methods: 'Electronic screening' of Expressed Sequence Tag (EST) and genomic databases, followed by RT-PCR and Northern blot analysis. Results: Rodent ESTs and genomic sequences homologous to HE3, HE4 and Ce8/Ly6G5C were identified in the public databases and the 'full-length' rat cDNAs cloned. To emphasise their homology to the human and canine genes, they were named Me3/Re3, Me4/Re4 and Re8 for mouse and rat counterparts, respectively. mRNA expression patterns were analysed in rats, including rat HEl and HE5/CD52 counterparts as controls. Re3 and Re8 mRNAs were only found in the rat epididymis, while Re4 showed a broader tissue distribution. Within the epididymis, Re3 and Re4 mRNAs were detected in all regions; Re8, on the other hand, was restricted to the caput. During postnatal development, Re3 and control mRNAs were found from the earliest stages investigated, while Re8 mRNA was observed only from day 24 postnatum, corresponding to the onset of spermatogenesis in the prepubertal testis. Castration and testosterone supplementation of adult male rats suggested that none of the cloned mRNAs was directly androgen-regulated. Efferent duct ligation, however, showed that Re8 mRNA levels depended on testicular factors other than androgens. Conclusion: The novel rodent cDNAs can now be used to monitor epididymal gene expression more closely and to set up various regulatory and functional studies.展开更多
In an attempt to isolate and identify the target genes relevant to salt tolerance in a mangrove plant （Sesuvium portulacastrum L.）, a subtracted cDNA library was constructed via suppressive subtractive hybridization...In an attempt to isolate and identify the target genes relevant to salt tolerance in a mangrove plant （Sesuvium portulacastrum L.）, a subtracted cDNA library was constructed via suppressive subtractive hybridization （SSH）, in which the poly（A）＋RNA isolated from salt-tolerant S. portulacastrum leaves was used as a tester, whereas the driver was poly（A）＋RNA, derived from salt-sensitive S. portulacastrum leaves. Screening of this subtracted cDNA library revealed five clones, of which the expression levels in the salt-tolerant plant were markedly higher than those observed in the salt-sensitive plant, indicating that these candidate clones may be involved in salt-tolerance pathways. Among the clones isolated, P66, P175, and P233 are novel because no significant similarity was obtained upon alignment with the GenBank database. Clone P89 demonstrated high homology with NADPH of Arabidopsis thaliana, whereas clone P152 was highly homologous with the gene encoding late embryogenesis abundant （LEA） protein of A. thaliana. The full-length gene of clone P152, with a predicated 344 amino acid residues, was shown to bear LEA-2 domains, a signature motif for proteins that have been enriched under salty and drought conditions. It is thus implied that clone P152 would be a salt-tolerance gene of S. portulacastrum. In addition, we have also developed a strategy for the extraction of total RNA from mangrove plants.展开更多
文摘Cinnamoyl-CoA reductase (CCR) is responsible for the first committed reaction in monolignol biosynthesis, which diverts phenylpropanoid-derived metabolites into the biosynthesis of lignin. To gain a better understanding of the lion biosynthesis in wheat development, two cDNAs encoding CCR were identified from wheat (Triticum aestivum L. cv. H4564). DNA sequence analyses indicated that the two cDNAs represent two classes of CCR. RT-PCR and Northern blot hybridization demonstrated that one of them, W-cr6, was expressed actively in stem and leaf tissue, the other one, W-cr19, was expressed in root and stem tissue. The results suggested that there are at least two genes encoded for CCR existing in wheat genome.
文摘The nucleotide sequences of the open reading frames of cDNAs for selenoprotein W from skeletal muscle of rat, mouse, sheep, rhesus monkey and human are reported. Theoretical translation of the coding sequences indicated highly similar proteins of 88 (mouse and rat) or 87 (human, monkey and sheep) amino acids. In 73 of 88 positions the specified amino acids are identical for all five proteins. TGA encoding selenocysteine is the 13th codon of all the cDNAs. The rnouse, rat and sheep open reading frames terminate with TGA but the human and rhesus monkey coding regions terminate with TAA. The encoded amino acid sequences are identical for the rat and mouse proteins, and for the human and monkey proteins. The similarity of the cDNAs continues in the 3' noncoding regions through the putative selenocysteine insertion sequence (SEClS) elements which are required for correct interpretation of the selenocysteine codon. The region between the SECIS elements and the polyadenylation signals showed much lower similarity. The cloned rat gene for selenoprotein W is 5000 bases long,with the 663 bases of the cDNA in six exons. The transcription start site was identified by nuclease protection assay to be 16 bases upstream of the longest cDNA clone. A canonical TATA box occurs 150 bases upstream, but the assay did not indicate the presence of longer mRNAs
文摘Total mRNA was extracted from a venom gland of snake Daboia russellii siamensis following the manufacturer＇s protocol of the PolyATtract System 1000 kit purchased from Promega Biotech. cDNAs encoding C-type lectins were amplified by RT-PCR and subcloned into a pMD18-T vector. Fourteen positive clones were selected for nucleotide sequencing and seven cDNAs encoding various snake venom C-type lectin-like protein precursors, designated as DRS-L1, DRS-L2, DRS-L3, DRS-L4 DRS-L5, DRS-L6 and DRS-L7, were obtained. Amino acid sequences of these proteins were deduced and each contains a carbohydrate recognition domain. Of all the deduced protein sequences, only DRS-L1 seemed to represent a closer sequence similarity to α subunits of other known snake venom C-type lectin-like proteins using the BLAST program. Homology comparison combined with analysis of cysteine position indicate that DRS-L1 and DRS-L2 are probably the light chain LC2 and LC1 of factor X activator from Daboia russellii siamensis venom, respectively. DRS-L3 and DRS-L4 might be the β subunits of higher molecular weight C-type lectin-like proteins while DRS-L5 and DRS-L6 might be β subunits of lower molecular weight C-type lectin-like proteins. DRS-L7 might be the β subunit of a platelet membrane glycoprotein Ib-binding protein similar to echicetin.
文摘Heavy metal contamination of soil has become a major environmental concern worldwide over the past several decades,the exploitation and application of heavy metal hyperaccumulating plants will defend the safety of food and environment on which human life relied,whereas using natural hyperaccumulators is insufficient,due
文摘<abstract>Aim: Identification of the rodent counterparts of human and canine epididymal cDNAs HE3, HE4 and Ce8/Ly6G5C by sequence homology and analysis of their expression patterns and regulation level in the rat. Methods: 'Electronic screening' of Expressed Sequence Tag (EST) and genomic databases, followed by RT-PCR and Northern blot analysis. Results: Rodent ESTs and genomic sequences homologous to HE3, HE4 and Ce8/Ly6G5C were identified in the public databases and the 'full-length' rat cDNAs cloned. To emphasise their homology to the human and canine genes, they were named Me3/Re3, Me4/Re4 and Re8 for mouse and rat counterparts, respectively. mRNA expression patterns were analysed in rats, including rat HEl and HE5/CD52 counterparts as controls. Re3 and Re8 mRNAs were only found in the rat epididymis, while Re4 showed a broader tissue distribution. Within the epididymis, Re3 and Re4 mRNAs were detected in all regions; Re8, on the other hand, was restricted to the caput. During postnatal development, Re3 and control mRNAs were found from the earliest stages investigated, while Re8 mRNA was observed only from day 24 postnatum, corresponding to the onset of spermatogenesis in the prepubertal testis. Castration and testosterone supplementation of adult male rats suggested that none of the cloned mRNAs was directly androgen-regulated. Efferent duct ligation, however, showed that Re8 mRNA levels depended on testicular factors other than androgens. Conclusion: The novel rodent cDNAs can now be used to monitor epididymal gene expression more closely and to set up various regulatory and functional studies.
文摘In an attempt to isolate and identify the target genes relevant to salt tolerance in a mangrove plant （Sesuvium portulacastrum L.）, a subtracted cDNA library was constructed via suppressive subtractive hybridization （SSH）, in which the poly（A）＋RNA isolated from salt-tolerant S. portulacastrum leaves was used as a tester, whereas the driver was poly（A）＋RNA, derived from salt-sensitive S. portulacastrum leaves. Screening of this subtracted cDNA library revealed five clones, of which the expression levels in the salt-tolerant plant were markedly higher than those observed in the salt-sensitive plant, indicating that these candidate clones may be involved in salt-tolerance pathways. Among the clones isolated, P66, P175, and P233 are novel because no significant similarity was obtained upon alignment with the GenBank database. Clone P89 demonstrated high homology with NADPH of Arabidopsis thaliana, whereas clone P152 was highly homologous with the gene encoding late embryogenesis abundant （LEA） protein of A. thaliana. The full-length gene of clone P152, with a predicated 344 amino acid residues, was shown to bear LEA-2 domains, a signature motif for proteins that have been enriched under salty and drought conditions. It is thus implied that clone P152 would be a salt-tolerance gene of S. portulacastrum. In addition, we have also developed a strategy for the extraction of total RNA from mangrove plants.
