Evidence map›Paper›PMID 27216446›Full record

ArticleParasites & vectors2016

Characterization of an epimastigote-stage-specific hemoglobin receptor of Trypanosoma congolense.

Shino Yamasaki, Keisuke Suganuma, Junya Yamagishi, Masahito Asada, Naoaki Yokoyama, Shin-Ichiro Kawazu, Noboru Inoue

Open access · goldAbstract read
In one paragraph

Article in Parasites & vectors, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
0.2field-weighted citation impact, top 37% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed, 1 citations in OpenAlex.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 3 institutions in 1 country.

Shino YamasakiNational Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, Hokkaido, 080-8555, Japan.
Keisuke SuganumaNational Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, Hokkaido, 080-8555, Japan.
Junya YamagishiResearch Center for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido, 001-0020, Japan.
Masahito AsadaDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, 852-8523, Japan.
Naoaki YokoyamaNational Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, Hokkaido, 080-8555, Japan.
Shin-Ichiro KawazuNational Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, Hokkaido, 080-8555, Japan.
Noboru InoueNational Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, Hokkaido, 080-8555, Japan. ircpmi@obihiro.ac.jp.
Obihiro University of Agriculture and Veterinary Medicine · JPHokkaido University · JPNagasaki University · JP

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundSince Trypanosoma spp. lack a complete heme synthesis pathway, the parasites are totally dependent on their host for heme throughout all of the stages of their life-cycle. We herein report the identification and characterization of a T. congolense epimastigote form (EMF)-specific hemoglobin (Hb) receptor. The gene was initially reported to encode a T. congolense haptoglobin (Hp)-Hb complex receptor (TcHpHbR) based on its similarity to a gene encoding a T. brucei Hp-Hb complex receptor (TbHpHbR).

methodsTrypanosoma congolense IL3000 was used in this study. A TcHpHbR gene was PCR amplified from the parasite genome. The recombinant protein was used as an immunogen to raise antibodies for immunofluorescence assay and immunoblotting. Hemoglobin uptake by the parasite was examined by using Alexa 488 labelled Hb and visualized by confocal laser scanning microscopy. The qualitative and quantitative interaction between TcHpHbR and its ligand were measured using a surface plasmon resonance assay.

resultsWe found that, unlike TbHpHbR, TcHpHbR was exclusively expressed in the EMF stage at RNA and protein levels. The recombinant TcHpHbR (rTcHpHbR) was co-precipitated with free-Hb in a GST-pull down assay. Surface plasmon resonance revealed that rTcHpHbR binds free-Hb with high affinity (dissociation constant (K d) = 2.1×10(-8) M) but free-Hp with low affinity (K d = 2.2×10(-7) M). Furthermore, Alexa 488-labelled-Hb was only taken up by the EMF and co-localized with tomato lectin, which is a marker of endocytic compartments (flagellar pocket and lysosome).

conclusionWe conclude that the T. congolense EMF takes up free-Hb via TcHpHbR, a receptor which is specific to this developmental stage. We therefore propose renaming TcHpHbR as T. congolense EMF-specific Hb receptor (TcEpHbR).

Indexed as

Amino Acid SequenceAnimalsFemaleHaptoglobinsHemoglobinsLife Cycle StagesMiceMice, Inbred ICRProtozoan ProteinsRecombinant ProteinsSequence AlignmentTrypanosoma congolensehaptoglobin-hemoglobin complexHaptoglobinsHemoglobinsProtozoan ProteinsRecombinant ProteinsEpimastigoteHemoglobin receptorTrypanosoma congolense

Identifiers

PMID27216446
PMCPMC4877808
OpenAlexW2407505063

What OpenQuestion holds

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LicenceCC BY
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.