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The classical arabinogalactan protein gene family of arabidopsis.

Arabinogalactan proteins (AGPs) are extracellular proteoglycans implicated in plant growth and development. We searched for classical AGPs in Arabidopsis by identifying expressed sequence tags based on the conserved domain structure of the predicted protein backbone. To confirm that these genes encoded bona fide AGPs, we purified native AGPs and then deglycosylated and deblocked them for N-terminal protein sequencing. In total, we identified 15 genes encoding the protein backbones of classical AGPs, including genes for AG peptides-AGPs with very short backbones (10 to 13 amino acid residues). Seven of the AGPs were verified as AGPs by protein sequencing. A gene encoding a putative cell adhesion molecule with AGP-like domains was also identified. This work provides a firm foundation for beginning functional analysis by using a genetic approach.

Amino Acid Sequence↗

Structure and function of a cellulase gene in redclaw crayfish, Cherax quadricarinatus.

The most abundant organic compound produced by plants is cellulose; however, it has long been accepted that most animals do not produce endogenous enzymes required for its degradation, but rely instead on symbiotic relationships with microbes that produce the necessary enzymes. Here, we present the genomic organisation of an endogenous glycosyl hydrolase family (GHF) 9 gene in redclaw crayfish (Cherax quadricarinatus), consolidated from a cDNA sequence determined by Byrne et al. [Gene 239 (1999) 317-324.]. Comparison with several other invertebrate GHF9 genes reveals the conservation of both intron position/phase and splice sequence, which adds support to an argument for an ancestral animal cellulase gene. Furthermore, two introns in plant GHF9 genes are also identical in position, implying a more ancient origin for this class of animal cellulase. Protein purification from redclaw gastric fluid via fast performance liquid chromatography (FPLC) indicated the presence of two endoglucanase enzymes. The molecular weights of these components were determined by matrix-assisted laser desorption/ionisation-time-of-flight (MALDI-TOF) to be 47,887 Da (Cel1) and 50,295 Da (Cel2). Cel1 is possibly the functional product of the described cellulase gene, with N-terminal amino acid residues identical to the translated amino acid sequence from the corresponding gene region. Cel2 was identical to Cel1 for 7 of 11 N-terminal residues and likely to be the product of a paralogous endoglucanase gene. These results suggest that redclaw crayfish possess at least one and possibly two functional, endoglucanase enzymes, although further work is required to confirm their origin and attributes.

Amino Acid Sequence↗

Molecular cloning and heterologous expression of beta1,2-xylosyltransferase and core alpha1,3-fucosyltransferase from maize.

Maize is considered a promising alternative production system for pharmaceutically relevant proteins. However, like in all other plant species asparagine-linked oligosaccharides of maize glycoproteins are modified with beta1,2-xylose and core alpha1,3-fucose sugar residues, which are considered to be immunogenic in mammals. This altered N-glycosylation when compared to mammalian cells may reduce the potential of maize as a production system for heterologous glycoproteins. Here we report the cloning and characterization of the cDNA sequences coding for the maize enzymes beta1,2-xylosyltransferase (XylT) and core alpha1,3-fucosyltransferase (FucT). The cloned XylT and FucT cDNAs were shown to encode enzymatically active proteins, which were independently able to convert a mammalian acceptor glycoprotein into an antigen binding anti-plant N-glycan antibodies. The complete sequence of the XylT gene was determined. Evidence for the presence of at least three XylT and FucT gene loci in the maize genome was obtained. The identification of the two enzymes and their genes will allow the targeted downregulation or even elimination of beta1,2-xylose and core alpha1,3-fucose addition to recombinant glycoproteins produced in maize.

Amino Acid Sequence↗

Evolutionary relationships of the glucokinase from the amitochondriate protist, Trichomonas vaginalis.

Two genes coding for Trichomonas vaginalis glucokinase were isolated and sequenced. The putative translation products have molecular masses of 41,584 and 41,772 Da, corresponding to 375 and 377 amino acids, respectively. These values agree with data determined by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for the enzyme purified from the organism. The two sequences showed 78% amino acid identity. The sequences and their phylogenetic reconstruction show that they are members of a glucokinase/fructokinase protein family found in eubacteria and also in the eukaryote Giardia lamblia and are only distantly related to typical eukaryotic hexokinases. The results indicate that the evolutionary past of this enzyme, catalyzing the first step of glycolysis in T. vaginalis, is different from that of the enzyme performing this key role in almost all other eukaryotes.

Amino Acid Sequence↗

Sequence of a cDNA encoding turtle high mobility group 1 protein.

In order to understand sequence information about turtle HMG1 gene, a cDNA encoding HMG1 protein of the Chinese soft-shell turtle (Pelodiscus sinensis) was amplified by RT-PCR from kidney total RNA, and was cloned, sequenced and analyzed. The results revealed that the open reading frame (ORF) of turtle HMG1 cDNA is 606 bp long. The ORF codifies 202 amino acid residues, from which two DNA-binding domains and one polyacidic region are derived. The DNA-binding domains share higher amino acid identity with homologues sequences of chicken (96.5%) and mammalian (74%) than homologues sequence of rainbow trout (67%). The polyacidic region shows 84.6% amino acid homology with the equivalent region of chicken HMG1 cDNA. Turtle HMG1 protein contains 3 Cys residues located at completely conserved positions. Conservation in sequence and structure suggests that the functions of turtle HMG1 cDNA may be highly conserved during evolution. To our knowledge, this is the first report of HMG1 cDNA sequence in any reptilian.

Amino Acid Sequence↗

cDNA sequence, 5'-flanking region, and promoter activity of the Neotomodon alstoni alstoni Clara cell secretory protein gene.

To better understand the phylogenetic divergence and the species-specific characteristics of the Clara cell secretory protein (CCSP), we cloned the cDNA encoding the neotomodon CCSP (nCCSP) and analyzed its tissue-specific expression. The full-length cDNA is 451bp long and predicts an amino acid sequence of 93 residues. Northern blot analysis from different neotomodon tissues demonstrated that the mRNA of CCSP appears to be solely expressed in the lung. To study the transcriptional regulation of the CCSP gene, we cloned the 5'-flanking region of the nCCSP gene and compared its features with those previously reported for the hamster gene. The neotomodon and hamster genes share 89% sequence homology in their promoter region as well as a number of conserved cis-acting elements. However, in H441 cells the expression of a reporter gene driven by the nCCSP promoter was about 4-fold greater than its hamster counterpart. Functional analysis of progressive 5'-deletion mutants identified a region involved in the higher transcriptional activity of the neotomodon promoter.

5' Flanking Region↗

Identification of the gene for the monomeric alkaline phosphatase of Vibrio cholerae serogroup O1 strain.

Alkaline phosphatase (APase) of Vibrio cholerae is the first monomeric alkaline phosphatase reported [Roy, N.K., Ghosh, R.K., Das, J., 1982a. Monomeric alkaline phosphatase of V. cholerae. J. Bacteriol. 150, 1033-1039.]. The gene (phoA(VC)) encoding this enzyme is not identified in the published genome sequence of the V. cholerae serogroup O1 El Tor strain N16961 [Heidelberg et al., 2000, DNA sequence of both the chromosome of cholera pathogen V. cholerae. Nature 406, 477-484.]. However two genes (phoB(VC) and phoR(VC)) regulating the synthesis of alkaline phosphatase in this organism, equivalent to phoB and phoR of Escherichia coli, are located in tandem on chromosome I of V. cholerae. We have identified the phoA(VC) gene on the N16961 genome sequence by amino acid sequence analysis of the purified alkaline phosphatase of V. cholerae classical strain 569B followed by BLAST search. The gene was found to be located on the hypothetical protein locus VCA0033 of chromosome II. The identity of the gene was confirmed by expressing the cloned VCA0033 locus in phoA mutant E. coli E15 and JC9223 cells and isolating V. cholerae monomeric alkaline phosphatase. Insertional inactivation of the gene also resulted in complete loss of the phenotype. Unlike in E. coli where phoB, phoR and phoA are closely linked, phoA(VC) is not linked to phoB(VC) and phoR(VC).

Alkaline Phosphatase↗

Isolation and sequence analysis of a cDNA and a related gene for cytochrome P450 proteins from Solanum chacoense.

Inosine-containing degenerate PCR primers corresponding to the heme-binding domain of cytochrome P450 proteins have been synthesized and used for cloning cDNAs by the RT-PCR technique from Solanum chacoense. One clone in which the primer was immediately followed by sequences corresponding to the remaining part of the conserved domain was obtained. A leaf cDNA and a genomic library were constructed from S. chacoense. Clones homologous to the PCR fragment were isolated by plaque hybridization from both libraries (CYPs.ch-1 and CYPs.ch-2, respectively). Based on DNA sequence analysis, the selected clones are 87.6% identical and belong to the CYP71 family. The CYPs.ch genes are present in multiple copies in the S. chacoense as well as in the S. tuberosum genome with some polymorphisms. The CYPs.ch transcripts are slightly induced by methyl jasmonate and abscisic acid in S. chacoense foliage.

Amino Acid Sequence↗

A mutation in the Corynebacterium glutamicum ltsA gene causes susceptibility to lysozyme, temperature-sensitive growth, and L-glutamate production.

The Corynebacterium glutamicum mutant KY9714, originally isolated as a lysozyme-sensitive mutant, does not grow at 37 degrees C. Complementation tests and DNA sequencing analysis revealed that a mutation in a single gene of 1,920 bp, ltsA (lysozyme and temperature sensitive), was responsible for its lysozyme sensitivity and temperature sensitivity. The ltsA gene encodes a protein homologous to the glutamine-dependent asparagine synthetases of various organisms, but it could not rescue the asparagine auxotrophy of an Escherichia coli asnA asnB double mutant. Replacement of the N-terminal Cys residue (which is conserved in glutamine-dependent amidotransferases and is essential for enzyme activity) by an Ala residue resulted in the loss of complementation in C. glutamicum. The mutant ltsA gene has an amber mutation, and the disruption of the ltsA gene caused lysozyme and temperature sensitivity similar to that in the KY9714 mutant. L-Glutamate production was induced by elevating growth temperature in the disruptant. These results indicate that the ltsA gene encodes a novel glutamine-dependent amidotransferase that is involved in the mechanisms of formation of rigid cell wall structure and in the L-glutamate production of C. glutamicum.

Aspartate-Ammonia Ligase↗

The fifth allele of the human deoxyribonuclease I (DNase I) polymorphism.

The fifth allele, DNASE1*5, of human deoxyribonuclease I (DNase I) has been discovered. Polymerase chain reaction fragments containing exon 5 of the DNase I gene were screened for DNA polymorphism using single-strand conformation polymorphism (SSCP) analysis. DNAs from 114 unrelated Japanese and 81 German individuals were tested and a new variant was detected. By DNA sequencing analysis, this variant was found to be caused by a heterozygous G-A transition at nucleotide position 1227 that results in a Val to Met substitution at amino acid position 92 of the mature enzyme. The nucleotide substitution was also confirmed by mismatched polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis. Genotyping of the variant could be carried out by three independent reactions based on PCR amplification, and phenotyping by isoelectric focusing followed by immunostaining. The results supported the presence of the fifth codominant allele, DNASE1*5, which generates a new isozyme.

Alleles↗

Varicella-zoster virus gene 66 transcription and translation in latently infected human Ganglia.

Latent infection with varicella-zoster virus (VZV) is characterized by restricted virus gene expression and the absence of virus production. Of the approximately 70 predicted VZV genes, only five (genes 4, 21, 29, 62, and 63) have been shown by multiple techniques to be transcribed during latency. IE62, the protein product of VZV gene 62, is the major immediate-early (IE) virus-encoded transactivator of viral gene transcription and plays a pivotal role in transactivating viral genes during lytic infection. The protein kinase (66-pk) encoded by VZV gene 66 phosphorylates IE62, resulting in cytoplasmic accumulation of IE62 that mitigates nuclear IE62-induced gene activation. Analysis of latently infected human trigeminal ganglia for 66-pk expression by reverse transcriptase-dependent nested PCR, including DNA sequence analysis, in situ hybridization, and immunohistochemistry, revealed VZV open reading frame 66 to be a previously unrecognized latently expressed virus gene and suggests that prevention of IE62 import to the nucleus by VZV 66-pk phosphorylation is one possible mechanism by which VZV latency is maintained.

Base Sequence↗

Characterization of acyl-CoA-binding protein (ACBP) in the pheromone gland of the silkworm, Bombyx mori.

Various fatty acyl-CoAs are involved as intermediates or precursors of sex pheromone components in the biosynthetic pathway of the pheromones in many lepidopteran insects. We have purified a 10-kDa protein from the cytosolic fraction of Bombyx mori pheromone glands by using affinity chromatography with a palmitoyl-CoA-agarose column and reversed-phase HPLC. Amino acid sequence analysis of the fragment peptides obtained from the purified protein, and a homology search, revealed that this protein was a member of acyl-CoA-binding proteins (ACBPs). MALDI-TOF mass spectral analysis of the purified protein and cloning of the gene from a pheromone gland cDNA library confirmed B. mori ACBP to be a 90 amino acid protein with 78.9% identity to that of Manduca sexta ACBP. The secondary structure of the recombinant B. mori ACBP was determined by NMR spectroscopy. Northern blot analysis demonstrated that B. mori ACBP was predominantly expressed in the pheromone gland and the corresponding transcript was expressed from the day before adult eclosion. Present results suggest that ACBP plays a significant role in the production of sex pheromones regulated by the neurohormone, pheromone biosynthesis activating neuropeptide (PBAN).

Acyl Coenzyme A↗

Genetic analysis of a Japanese patient with butyrylcholinesterase deficiency.

A patient (64-year-old, male) with familial cholinesterasemia caused by BChE deficiency was studied. DNA sequence analysis of all exons identified a point mutation, an A-->G transition at codon 128, resulting in a Tyr-->Cys substitution. The propositus showed extremely low BChE activity, but his other family members (three individuals) showed from intermediate to normal BChE activity. An immunological method revealed the absence of BChE protein in serum of the propositus. Both PCR primer introduced restriction analysis (PCR-PIRA) and sequence analysis revealed all three family members to be heterozygotes for this mutation.

Asian People↗

Wide phylogenetic distribution of Scorpine and long-chain beta-KTx-like peptides in scorpion venoms: identification of "orphan" components.

Scorpine and toxins specific for potassium channels of the family beta (beta-Ktx) are two types of structurally related scorpion venom components, characterized by an unusually long extended N-terminal segment, followed by a Cys-rich domain with some resemblance to other scorpion toxins. In this communication, we report evidence supporting the ubiquitous presence of Scorpine and beta-KTx-like polypeptides and their precursors in scorpions of the genus Tityus of the family Buthidae, but also included is the first example of such peptides in scorpions from the family Iuridae. Seven new beta-KTxs or Scorpine-like peptides and precursors are reported: five from the genus Tityus (T. costatus, T. discrepans and T. trivittatus) and two from Hadrurus gertschi. The cDNA precursors for all of these peptides were obtained by molecular cloning and their presence in the venoms were confirmed for various peptides. Analysis of the sequences revealed the existence of at least three distinct groups: (1) beta-KTx-like peptides from buthids; (2) Scorpine-like peptides from scorpionid and iurid scorpions; (3) heterogeneous peptides similar to BmTXKbeta of buthids and iurids. The biological function for most of these peptides is not well known; that is why they are here considered "orphan" peptides.

Amino Acid Sequence↗

Genetic variation within and among fragmented populations of lesser prairie-chickens (Tympanuchus pallidicinctus).

As a result of recurrent droughts and anthropogenic factors, the range of the lesser prairie-chicken (Tympanuchus pallidicinctus) has contracted by 92% and the population has been reduced by approximately 97% in the past century, resulting in the smallest population size and most restricted geographical distribution of any North American grouse. We examined genetic variation through DNA sequence analysis of 478 base pairs of the mitochondrial genome and by assaying allelic variation at five microsatellite loci from lesser prairie-chickens collected on 20 leks in western Oklahoma and east-central New Mexico. Traditional population genetic analyses indicate that lesser prairie-chickens maintain high levels of genetic variation at both nuclear and mitochondrial loci. Although some genetic structuring among lesser prairie-chicken leks was detected within Oklahoma and New Mexico for both nuclear and mitochondrial loci, high levels of differentiation were detected between Oklahoma and New Mexico populations. Nested-clade analysis of mitochondrial haplotypes revealed that both historic and contemporary processes have influenced patterns of haplotype distributions and that historic processes have most likely led to the level of differentiation found between the Oklahoma and New Mexico populations.

Alleles↗

Gene discovery and gene function assignment in filamentous fungi.

Filamentous fungi are a large group of diverse and economically important microorganisms. Large-scale gene disruption strategies developed in budding yeast are not applicable to these organisms because of their larger genomes and lower rate of targeted integration (TI) during transformation. We developed transposon-arrayed gene knockouts (TAGKO) to discover genes and simultaneously create gene disruption cassettes for subsequent transformation and mutant analysis. Transposons carrying a bacterial and fungal drug resistance marker are used to mutagenize individual cosmids or entire libraries in vitro. Cosmids are annotated by DNA sequence analysis at the transposon insertion sites, and cosmid inserts are liberated to direct insertional mutagenesis events in the genome. Based on saturation analysis of a cosmid insert and insertions in a fungal cosmid library, we show that TAGKO can be used to rapidly identify and mutate genes. We further show that insertions can create alterations in gene expression, and we have used this approach to investigate an amino acid oxidation pathway in two important fungal phytopathogens.

Alleles↗

Point mutations of the topoisomerase IIalpha gene in patients with small cell lung cancer treated with etoposide.

Reverse transcription-PCR-single-strand conformation polymorphism analysis was performed to detect topoisomerase IIalpha mutations using total RNA from 19 bronchial biopsy specimens obtained from 13 patients with small cell lung cancer. An abnormally migrating single-strand conformation polymorphism band was observed in one tumor sample from a patient treated with etoposide-containing chemotherapy. DNA sequence analysis of this tumor showed two transversions at codons 486 (G to A) and 494 (A to G), resulting in two missense mutations (Arg to Lys and Glu to Gly, respectively). The codon 486 mutation was identical to that previously found in two cell lines selected for amsacrine resistance. These results demonstrate that mutations of topoisomerase IIalpha occur in patients with small cell lung cancer. The significance of these mutations in the development of resistance to etoposide needs further investigation.

Aged↗