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Lauwaet T Smith AJ Reiner DS Romijn EP Wong CC Davids BJ Shah SA Yates JR Gillin FD 《International journal for parasitology》2011,41(10):1079-1092
Giardia lamblia is a flagellated protozoan parasite and a major cause of diarrhoea in humans. Its microtubular cytoskeleton mediates trophozoite motility, attachment and cytokinesis, and is characterised by an attachment disk and eight flagella that are each nucleated in a basal body. To date, only 10 giardial basal body proteins have been identified, including universal signalling proteins that are important for regulating mitosis or differentiation. In this study, we have exploited bioinformatics and proteomic approaches to identify new Giardia basal body proteins and confocal microscopy to confirm their localisation in interphase trophozoites. This approach identified 75 homologs of conserved basal body proteins in the genome including 65 not previously known to be associated with Giardia basal bodies. Thirteen proteins were confirmed to co-localise with centrin to the Giardia basal bodies. We also demonstrate that most basal body proteins localise to additional cytoskeletal structures in interphase trophozoites. This might help to explain the roles of the four pairs of flagella and Giardia-specific organelles in motility and differentiation. A deeper understanding of the composition of the Giardia basal bodies will contribute insights into the complex signalling pathways that regulate its unique cytoskeleton and the biological divergence of these conserved organelles. 相似文献
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Elucidation of genome sequence provides an excellent platform to understand detailed complexity of the various gene families.
Hsp100 is an important family of chaperones in diverse living systems. There are eight putative gene loci encoding for Hsp100
proteins in Arabidopsis genome. In rice, two full-length Hsp100 cDNAs have been isolated and sequenced so far. Analysis of rice genomic sequence
by in silico approach showed that two isolated rice Hsp100 cDNAs correspond to Os05g44340 and Os02g32520 genes in the rice genome database. There appears to be three additional proteins (encoded by Os03g31300, Os04g32560 and Os04g33210 gene loci) that are variably homologous to Os05g44340 and Os02g32520 throughout the entire amino acid sequence. The above
five rice Hsp100 genes show significant similarities in the signature sequences known to be conserved among Hsp100 proteins. While Os05g44340 encodes cytoplasmic Hsp100 protein, those encoded by the other four genes are predicted to have chloroplast transit peptides. 相似文献
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Sang Oh Kwon Sung Gyun Kang Soon-Ho Park Young Hwan Kim Jong-Soon Choi Jung-Hyun Lee Seung Il Kim 《Extremophiles : life under extreme conditions》2009,13(2):379-387
Thermococcus onnurineus NA1, a sulfur-reducing hyperthermophilic archaeon, was isolated from a deep-sea hydrothermal vent area in Papua New Guinea.
The strain requires elemental sulfur as a terminal electron acceptor for heterotrophic growth on peptides, amino acids and
sugars. Recently, genome sequencing of Thermococcus onnurineus NA1 was completed. In this study, 2-DE/MS–MS analysis of the cytosolic proteome was performed to elucidate the metabolic
characterization of Thermococcus onnurineus NA1 at the protein level. Among the 1,136 visualized protein spots, 110 proteins were identified. Enzymes related to metabolic
pathways of amino acids utilization, glycolysis, pyruvate conversion, ATP synthesis, and protein synthesis were identified
as abundant proteins, highlighting the fact that these are major metabolic pathways in Thermococcus onnurineus NA1. Interestingly, multiple spots of phosphoenolpyruvate synthetase and elongation factor Tu were found on 2D gels generated
by truncation at the N-terminus, implicating the cellular regulatory mechanism of this key enzyme by protease degradation.
In addition to the proteins involved in metabolic systems, we also identified various proteases and stress-related proteins.
The proteomic characterization of abundantly induced proteins using 2-DE/MS–MS enables a better understanding of Thermococcus onnurineus NA1 metabolism. 相似文献
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Heat shock proteins are ubiquitous and highly conserved. Recently they have become implicated in the import of proteins into organelles. All the heat shock genes characterized to date, however, are known or assumed to be encoded in the nuclear genome even if the corresponding protein can be localised in the mitochondrion or chloroplast. In contrast, we identify here an hsp70 gene in the unicellular chromophytic alga Pavlova lutherii which is located on the chloroplast genome. Localisation of this gene to the chloroplast chromosome is confirmed by Southern blot analysis and pulse-field gel electrophoresis which also reveals that the length of the P. lutherii chloroplast chromosome is 115 kb. We compare the predicted protein of this hsp70 gene with that of maize and of the analogous proteins in the prokaryotic organisms Escherichia coli and Synechocystis PCC6803. The greatest identity is found with the cyanobacterium Synechocystis PCC6803. 相似文献
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【背景】铜绿微囊藻(Microcystis aeruginosa)广泛分布于温带湖泊,因产生微囊藻毒素且易成为蓝藻水华优势藻株而备受关注。【目的】基于全基因组序列分析和基因转录水平验证,阐明从巢湖新分离的铜绿微囊藻Chao 1910的主要代谢通路和磷营养高效利用机制。【方法】通过第三代测序技术拼接获得Chao1910的全基因组序列,完成主要代谢通路的基因注释,并对与蓝藻水华优势藻株形成相关的磷代谢通路进行深入分析。【结果】比较基因组学表明,Chao1910藻株与日本铜绿微囊藻NIES-843的亲缘关系最近,其糖酵解、磷酸戊糖途径和核苷酸合成等代谢通路的基因组成非常保守,同时具有完整的磷转运、磷吸收、多聚磷酸盐合成/分解等磷营养高效利用的通路。不同于其他铜绿微囊藻,Chao 1910藻株不具有微囊藻毒素合成基因簇,推测其主要依靠对磷营养的高效利用获取生存竞争优势。【结论】Chao1910藻株是巢湖首株完成全基因组测序的铜绿微囊藻,这将有助于揭示其获得生存竞争优势的分子机制,为遏制巢湖蓝藻水华暴发提供依据。 相似文献
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Alexander R. Paredez Arash Nayeri Jennifer W. Xu Jana Krtková W. Zacheus Cande 《Eukaryotic cell》2014,13(6):776-784
Consistent with its proposed status as an early branching eukaryote, Giardia has the most divergent actin of any eukaryote and lacks core actin regulators. Although conserved actin-binding proteins are missing from Giardia, its actin is utilized similarly to that of other eukaryotes and functions in core cellular processes such as cellular organization, endocytosis, and cytokinesis. We set out to identify actin-binding proteins in Giardia using affinity purification coupled with mass spectroscopy (multidimensional protein identification technology [MudPIT]) and have identified >80 putative actin-binding proteins. Several of these have homology to conserved proteins known to complex with actin for functions in the nucleus and flagella. We validated localization and interaction for seven of these proteins, including 14-3-3, a known cytoskeletal regulator with a controversial relationship to actin. Our results indicate that although Giardia lacks canonical actin-binding proteins, there is a conserved set of actin-interacting proteins that are evolutionarily indispensable and perhaps represent some of the earliest functions of the actin cytoskeleton. 相似文献
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Summary Wounding in higher plants leads to an increased synthesis of specific messenger RNAs. A cDNA clone complementary to a wound-induced message from potato tubers was used to isolate a lambda clone from a genomic library of Salanum tuberosum var. Maris Piper. DNA sequence analysis has shown that this single genomic clone contains two novel wound-induced genes, called win1 and win2, organised in close tandem array. The coding sequences of these two genes are highly homologous and are interrupted by a single intron. However, the sequences of the introns and flanking regions have diverged widely. Win1 and win2 encode cysteine-rich proteins of 200 and 211 amino-acids, respectively, which show striking homologies to several chitin-binding proteins. Southern analysis of genomic DNA has shown that win1 and win2 are members of a small multi-gene family which is estimated to have a minimum of five members per haploid genome of Maris Piper and appears to be conserved within the Solanaceae. We have shown by Northern analysis and S1 mapping that the two genes exhibit differential organ-specific expression after the wounding of a potato plant. 相似文献
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Transmembrane 4 superfamily (TM4SF) molecules are predominantly mammalian cell surface glycoproteins that are thought to transduce
signals mediating cell development, activation, and motility. Analysis of the Genpept sequence database reveals YKK8, a novel
member of the TM4SF in the nematode,Caenorhabditis elegans. YKK8 is a putative 27.4-kDa protein encoded by a gene on chromosome III of theC. elegans genome (Wilson et al. [1994]Nature 368:32–38). The assignment of YKK8 to the TM4SF is justified by three criteria: statistical comparison of protein sequences,
conserved TM4SF protein sequence motifs, and conserved TM4SF intron/exon boundaries in the genomic sequence. The discovery
of a TM4SF molecule in the nematode extends this superfamily to a more primitive branch of the phylogenetic tree and suggests
a fundamental role for TM4SF molecules in biology.
Correspondence to: M.G. Tomlinson 相似文献
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Marie-Michelle Genois Eric R. Paquet Marie-Claude N. Laffitte Ranjan Maity Amélie Rodrigue Marc Ouellette Jean-Yves Masson 《Microbiology and molecular biology reviews》2014,78(1):40-73
SUMMARY
All living organisms are continuously faced with endogenous or exogenous stress conditions affecting genome stability. DNA repair pathways act as a defense mechanism, which is essential to maintain DNA integrity. There is much to learn about the regulation and functions of these mechanisms, not only in human cells but also equally in divergent organisms. In trypanosomatids, DNA repair pathways protect the genome against mutations but also act as an adaptive mechanism to promote drug resistance. In this review, we scrutinize the molecular mechanisms and DNA repair pathways which are conserved in trypanosomatids. The recent advances made by the genome consortiums reveal the complete genomic sequences of several pathogens. Therefore, using bioinformatics and genomic sequences, we analyze the conservation of DNA repair proteins and their key protein motifs in trypanosomatids. We thus present a comprehensive view of DNA repair processes in trypanosomatids at the crossroads of DNA repair and drug resistance. 相似文献14.
Protein phosphatase 2A: identification in Oryza sativa of the gene encoding the regulatory A subunit 总被引:1,自引:0,他引:1
A 2225 bp cDNA, designated RPA1, was isolated from an Oryza sativa cDNA library. Analysis revealed a 1761 bp coding sequence with 15 non-identical repeat units. The ORF encoded the A regulatory subunit of protein phosphatase 2A (PP2A-A) as ascertained by complementation of the yeast tpd3 mutant defective in this gene. The corresponding genomic DNA from a rice genome BAC library revealed that the gene contains eleven introns. The rice genome contains only a single copy of this gene as judged by Southern blot analysis. The PP2A protein is highly conserved in nature; the rice protein shows 88% amino acid identity with its counterparts in Arabidopsis or Nicotiana tabacum. 相似文献
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【目的】通过解析拟茎点霉属XP-8的基因组序列信息,揭示该菌株潜在的代谢途径,并分析松脂醇及其糖苷化合物等次级代谢产物生物合成相关的关键基因。【方法】使用Illumina Hi Seq 2500高通量测序平台对拟茎点霉XP-8菌株进行全基因组测序,并通过不同软件对测序数据进行序列拼接,基因预测与功能注释。【结果】组装后的拟茎点霉XP-8基因组大小为55.2 Mb,GC含量53.5%,含有17094个蛋白编码基因和310个非编码基因。获得了松脂醇及其糖苷化合物等次级代谢产物生物合成相关的基因。系统发育分析揭示出拟茎点霉XP-8与5种子囊菌共有12635个同源基因和5626个基因家族。【结论】拟茎点霉XP-8具有用于合成松脂醇及其糖苷化合物等多种次级代谢物的基因组基础,为下一步的代谢工程改造提供依据。 相似文献
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Genomic analysis of <Emphasis Type="Italic">Acidianus hospitalis</Emphasis> W1 a host for studying crenarchaeal virus and plasmid life cycles 总被引:1,自引:0,他引:1
You XY Liu C Wang SY Jiang CY Shah SA Prangishvili D She Q Liu SJ Garrett RA 《Extremophiles : life under extreme conditions》2011,15(4):487-497
The Acidianus hospitalis W1 genome consists of a minimally sized chromosome of about 2.13 Mb and a conjugative plasmid pAH1 and it is a host for the
model filamentous lipothrixvirus AFV1. The chromosome carries three putative replication origins in conserved genomic regions
and two large regions where non-essential genes are clustered. Within these variable regions, a few orphan orfB and other elements of the IS200/607/605 family are concentrated with a novel class of MITE-like repeat elements. There are
also 26 highly diverse vapBC antitoxin–toxin gene pairs proposed to facilitate maintenance of local chromosomal regions and to minimise the impact of
environmental stress. Complex and partially defective CRISPR/Cas/Cmr immune systems are present and interspersed with five
vapBC gene pairs. Remnants of integrated viral genomes and plasmids are located at five intron-less tRNA genes and several non-coding
RNA genes are predicted that are conserved in other Sulfolobus genomes. The putative metabolic pathways for sulphur metabolism show some significant differences from those proposed for
other Acidianus and Sulfolobus species. The small and relatively stable genome of A. hospitalis W1 renders it a promising candidate for developing the first Acidianus genetic systems. 相似文献
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Nucleotide sugar interconversion pathways represent a series of enzymatic reactions by which plants synthesize activated monosaccharides for the incorporation into cell wall material. Although biochemical aspects of these metabolic pathways are reasonably well understood, the identification and characterization of genes encoding nucleotide sugar interconversion enzymes is still in its infancy. Arabidopsis mutants defective in the activation and interconversion of specific monosaccharides have recently become available, and several genes in these pathways have been cloned and characterized. The sequence determination of the entire Arabidopsis genome offers a unique opportunity to identify candidate genes encoding nucleotide sugar interconversion enzymes via sequence comparisons to bacterial homologues. An evaluation of the Arabidopsis databases suggests that the majority of these enzymes are encoded by small gene families, and that most of these coding regions are transcribed. Although most of the putative proteins are predicted to be soluble, others contain N-terminal extensions encompassing a transmembrane domain. This suggests that some nucleotide sugar interconversion enzymes are targeted to an endomembrane system, such as the Golgi apparatus, where they may co-localize with glycosyltransferases in cell wall synthesis. The functions of the predicted coding regions can most likely be established via reverse genetic approaches and the expression of proteins in heterologous systems. The genetic characterization of nucleotide sugar interconversion enzymes has the potential to understand the regulation of these complex metabolic pathways and to permit the modification of cell wall material by changing the availability of monosaccharide precursors. 相似文献
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Cástor Menéndez Gabor Igloi Hanspeter Henninger Roderich Brandsch 《Archives of microbiology》1995,164(2):142-151
A gene homologous tomoaA, the gene responsible for the expression of a protein involved in an early step in the synthesis of the molybdopterin cofactor
ofEscherichia coli, was found to be located 2.7-kb upstream of the nicotine dehydrogenase (ndh) operon on the catabolic plasmid pAO1 ofArthrobacter nicotinovorans. The MoaA protein, containing 354 amino acids, migrated on an SDS-polyacrylamide gel with an apparent molecular weight of
40,000, in good agreement with the predicted molecular weight of 38,880. The pAO1-encodedmoaA gene fromA. nicotinovorans was expressed inE. coli as an active protein that functionally complementedmoaA mutants. Its reduced amino acid sequence shows 43% identity to theE. coli MoaA, 44% to the NarAB gene product fromBacillus subtilis, and 42% to the gene product of two contiguous ORFs fromMethanobacterium formicicum. N-terminal sequences, including the motif CxxxCxYC, are conserved among the MoaA and NarAB proteins. This motif is also
present in proteins involved in PQQ cofactor synthesis in almost all the NifB proteins reported so far and in thefixZ gene product fromRhizobium leguminosarum. Mutagenesis of any of these three conserved cysteine residues to serine abolished the biological activity of MoaA, while
substitution of the tyrosine by either serine, phenylalanine, or alanine did not alter the capacity of the protein to complement
themoaA mutation inE. coli. A second Cys-rich domain with the motif FCxxC(13x)C is found close to the C-terminus of MoaA and NarAB proteins. These two
Cys-rich sequences may be involved in the coordination of a metal ions. The pAO1 copy ofmoaA may not be unique in theA. nicotinovorans genome since the molybdopterin cofactor oxidation products were detected in cell extracts from a plasmidless strain. 相似文献
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Neuronal communication involves the fusion of neurotransmitter filled synaptic vesicles with the presynaptic terminal. This
exocytotic event depends upon proteins present in three separate compartments: the synaptic vesicle, the synaptic cytosol,
and the presynaptic membrane. Recent data indicate that the basic components of exocytotic pathways, including those used
for neurotransmitter release, are conserved from yeast to human. Genetic dissection of the secretory pathway in yeast, identification
of the target proteins cleaved by the clostridial neurotoxins and biochemical characterization of the interactions of synaptic
proteins from vertebrates have converged to provide the SNARE (soluble NSF attachment protein receptor) hypothesis for vesicle
trafficking. This model proposes that proteins present in the vesicle (v-SNAREs) interact with membrane receptors (t-SNAREs)
to provide a molecular scaffold for cytosolic proteins involved in fusion. The hypothesis that these mechanisms function at
the synapse relies largely uponin vitro evidence. Recently, genetic approaches in mice, C.elegans and the fruitfly,Drosophila melanagaster, have been used to dissect thein vivo function of numerous proteins involved in synaptic transmission. This review covers recent progress and insights provided
by a genetic dissection of neurotransmitter release inDrosophila. In addition, we will provide evidence that the mechanisms for synaptic communication are highly conserved from invertebrates
to vertebrates, makingDrosophila an ideal model system to further unravel the intricacies of synaptic transmission. 相似文献