Abstract:
:Profilins are the key regulators of actin dynamics in all eukaryotic cells. However, little information is available on their biochemical properties and functions in kinetoplastids, such as Trypanosoma and Leishmania. We show here that Leishmania parasites express only one homolog of profilin (LdPfn), which catalyzes nucleotide exchange on G-actin and promotes actin polymerization at its low concentrations. However, at high concentrations, it strongly inhibits the polymerization process by sequestering actin monomers. We further demonstrate that LdPfn binds to actin in Leishmania promastigotes, by both immunofluorescence microscopy and IgG affinity chromatography. Further, we reveal that this protein besides binding to poly-null-proline motifs, also binds more efficiently to PI(3,5)P2, which is found on early or late endosomes or lysosomes, than to PI(4,5)P2 and PI(3,4,5)P3. Additionally, we show that heterozygous mutants of profilin display significantly slower growth and intracellular vesicle trafficking activity, which is reversed on episomal gene complementation. Together, these findings suggest that profilin regulates intracellular vesicle trafficking in Leishmania perhaps through its binding to polyphosphoinositides.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Ambaru B,Gopalsamy A,Tammana TVS,Subramanya HS,Gupta CMdoi
10.1016/j.molbiopara.2020.111280subject
Has Abstractpub_date
2020-07-01 00:00:00pages
111280eissn
0166-6851issn
1872-9428pii
S0166-6851(20)30044-Xjournal_volume
238pub_type
杂志文章abstract::The glycine cleavage complex (GCV) is a potential source of the one carbon donor 5,10-methylene-tetrahydrofolate (5,10-CH(2)-THF) in the malaria parasite Plasmodium falciparum. One carbon (C1) donor units are necessary for amino acid and nucleotide biosynthesis, and for the initiation of mitochondrial and plastid tran...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.04.005
更新日期:2010-08-01 00:00:00
abstract::The precursor of the glycosylphosphatidylinositol membrane anchor of the variant surface glycoprotein of Trypanosoma brucei is known as glycolipid A and it has the structure: EtN-PO4-6Man alpha 1-2Man alpha 1-6Man alpha 1-4GlcN alpha 1-6myo-inositol-PO4-(sn-1,2-dimyristoylglycerol). This precursor exists in equilibriu...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(96)02585-6
更新日期:1996-05-01 00:00:00
abstract::The ADP ribosylation factors (Arfs) are a highly conserved subfamily of the Ras small GTPases with crucial roles in vesicle budding and membrane trafficking. Unlike in other eukaryotes, the orthologue of Arf1 in the host bloodstream form of Trypanosoma brucei is essential for the maintenance of endocytosis. In contras...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2007.06.009
更新日期:2007-10-01 00:00:00
abstract::Trypanosoma brucei is a unicellular parasite that is transmitted from one mammalian host to the next by tsetse flies. The expression of many trypanosome genes is regulated during the life cycle but there is no evidence for developmental control of transcription by RNA polymerase II. T. brucei expresses at least two he...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(95)02503-0
更新日期:1995-12-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(01)00320-6
更新日期:2001-09-03 00:00:00
abstract::Adult Schistosoma mansoni worms rapidly degrade their endogenous glycogen stores immediately after isolation from the host. In NCTC 109 or in a diphasic culture medium the glycogen levels slowly recovered again after the initial decrease. The rapid degradation of glycogen could be prevented, even in a simple salt medi...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(87)90156-3
更新日期:1987-07-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(81)90084-0
更新日期:1981-04-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2019.111219
更新日期:2019-10-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(96)02673-4
更新日期:1996-10-30 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(87)90064-8
更新日期:1987-01-02 00:00:00
abstract::Evidence is presented that Giardia lamblia and Entamoeba histolytica, phylogenetically unrelated aerotolerant anaerobes, have crucial thiol groups on or easily accessible to their external surface. Both parasites were killed by three structurally unrelated thiol-blocking reagents which penetrate intact cells poorly or...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(84)90096-3
更新日期:1984-09-01 00:00:00
abstract::Surface proteins of male and female gametes of Plasmodium gallinaceum were radioiodinated by the lactoperoxidase method, immunoprecipitated with stage specific antisera and separated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Stage specificity of the surface antigens was further studied by competiti...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(84)90061-6
更新日期:1984-04-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2013.01.002
更新日期:2013-02-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(98)00005-x
更新日期:1998-05-01 00:00:00
abstract::Messenger RNA has been isolated from adults and eggs of Schistosoma mansoni and translated in vitro in mRNA dependent rabbit reticulocyte lysate. The in vitro translation products have been immunoprecipitated using a wide variety of hyperimmune and infection sera from rabbits, mice and humans. A large number of in vit...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(84)90029-x
更新日期:1984-03-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2013.04.006
更新日期:2013-05-01 00:00:00
abstract::Adenylosuccinate synthetase (AdSS) catalyses the Mg(2+) dependent formation of adenylosuccinate from IMP and aspartate, the reaction being driven by the hydrolysis of GTP to GDP. All characterized AdSS thus far exhibit a random kinetic mechanism. We present here kinetic evidence that unlike all other AdSS, Plasmodium ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2004.06.013
更新日期:2004-11-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2015.07.005
更新日期:2015-06-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(95)02562-6
更新日期:1996-02-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(96)02765-x
更新日期:1996-12-20 00:00:00
abstract::To investigate whether the lysosomes of Trypanosoma brucei are capable of uptake of macromolecules after internalization by the cell, we used Triton WR-1339, a non-digestible macromolecular compound, which is known to cause a marked decrease in the density of hepatic lysosomes due to massive intralysosomal storage. In...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(82)90077-9
更新日期:1982-09-01 00:00:00
abstract::The cysteine proteinase B of Leishmania parasites is an important virulence factor. In this study we have expressed, isolated and characterized for the first time a recombinant CPB from Leishmania braziliensis, the causative agent of mucocutaneous leishmaniosis. The mature region of the recombinant CPB shares a high p...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2008.06.005
更新日期:2008-10-01 00:00:00
abstract::Post-transcriptional regulation is a key feature controlling gene expression in the protozoan parasite Leishmania. The nine-nucleotide paraflagellar rod regulatory element (PRE) in the 3'UTR of Leishmania mexicana PFR2 is both necessary and sufficient for the observed 10-fold higher level of PFR2 mRNA in promastigotes...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2007.10.001
更新日期:2008-01-01 00:00:00
abstract::A family of Schistosoma mansoni proteins (18-22 kDa, pI 5.3-5.8) are biosynthesized in juvenile worms and immunoprecipitated by antibodies uniquely present in protective Fischer rat antiserum. A cDNA clone, lambda gt11-40, expressing epitopes common to this protein family was used to obtain a genomic DNA clone, by hyb...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(91)90132-p
更新日期:1991-11-01 00:00:00
abstract::The expressed sequence tag (EST) dataset of Toxoplasma gondii provides a wealth of information towards gene discovery. The complete cDNA and genomic sequence of EST tgc050 locus shows that it contains five copies of the conserved thrombospondin (TSP)-like motif present in a number of molecules with adhesive properties...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(96)02796-x
更新日期:1997-02-01 00:00:00
abstract::When the malarial parasite Plasmodium falciparum multiplies in erythrocytes it dramatically increases uptake of essential metabolic precursors (nucleosides, nucleobases and glucose) and export of lactic acid by undefined mechanisms. The first evidence is provided here, by a detailed study in Xenopus laevis oocytes, th...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(98)00024-3
更新日期:1998-05-15 00:00:00
abstract::The bloodstream forms of the protozoan parasite Trypanosoma brucei lack spectrally detectable cytochromes and satisfy energy requirements mainly by glycolysis. When infected blood is ingested by the tse-tse fly vector, the bloodstream form cells differentiate to procyclic forms that have fully functional mitochondria....
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(94)90080-9
更新日期:1994-06-01 00:00:00
abstract::Trypanosoma brucei survives in mammals by antigenic variation of its surface coat consisting of variant surface glycoprotein (VSG). Trypanosomes change coat mainly by replacing the transcribed VSG genes in an active telomeric expression site by a different VSG gene. There are about 20 different expression sites and tr...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
doi:10.1016/s0166-6851(01)00243-2
更新日期:2001-04-25 00:00:00
abstract::Lectins comprise a family of related proteins that mediate essential cell functions through binding to carbohydrates. Within this protein family, C-type lectins are defined by the requirement of calcium for optimal biologic activity. Using reverse transcription PCR, a cDNA corresponding to a putative C-type lectin has...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2006.10.017
更新日期:2007-02-01 00:00:00
abstract::GRA3 is a 30-kDa protein located inside the dense granules of Toxoplasma gondii. Following invasion and exocytosis of dense granules within the parasitophorous vacuole, GRA3 becomes associated with the parasitophorous vacuolar membrane (PVM) and extensions of the PVM which protrude into the cytoplasm. A partial cDNA e...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(94)90169-4
更新日期:1994-12-01 00:00:00