Evidence map›Paper›PMID 31860644›Full record

ArticlePloS one2019

Validation of Plasmodium vivax centromere and promoter activities using Plasmodium yoelii.

Kittisak Thawnashom, Miho Kaneko, Phonepadith Xangsayarath, Nattawat Chaiyawong, Kazuhide Yahata, Masahito Asada, John H Adams, Osamu Kaneko

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
0.7field-weighted citation impact, top 25% 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

3 citing papers in PubMed, 6 citations in OpenAlex.

  1. Article
  2. Review
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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

8 authors at 2 institutions in 3 countries.

Kittisak ThawnashomDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan.
Miho KanekoDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan.
Phonepadith XangsayarathDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan.
Nattawat ChaiyawongDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan.
Kazuhide YahataDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan.
Masahito AsadaDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan.ORCID 0000-0003-0042-6856
John H AdamsCenter for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, United States of America.
Osamu KanekoDepartment of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan.ORCID 0000-0003-0675-8296
Nagasaki University · JPUniversity of South Florida · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Plasmodium vivax is the leading cause of malaria outside Africa and represents a significant health and economic burden on affected countries. A major obstacle for P. vivax eradication is the dormant hypnozoite liver stage that causes relapse infections and the limited antimalarial drugs that clear this stage. Advances in studying the hypnozoite and other unique biological aspects of this parasite are hampered by the lack of a continuous in vitro laboratory culture system and poor availability of molecular tools for genetic manipulation. In this study, we aim to develop molecular tools that can be used for genetic manipulation of P. vivax. A putative P. vivax centromere sequence (PvCEN) was cloned and episomal centromere based plasmids expressing a GFP marker were constructed. Centromere activity was evaluated using a rodent malaria parasite Plasmodium yoelii. A plasmid carrying PvCEN was stably maintained in asexual-stage parasites in the absence of drug pressure, and approximately 45% of the parasites retained the plasmid four weeks later. The same retention rate was observed in parasites possessing a native P. yoelii centromere (PyCEN)-based control plasmid. The segregation efficiency of the plasmid per nuclear division was > 99% in PvCEN parasites, compared to ~90% in a control parasite harboring a plasmid without a centromere. In addition, we observed a clear GFP signal in both oocysts and salivary gland sporozoites isolated from mosquitoes. In blood-stage parasites after liver stage development, GFP positivity in PvCEN parasites was comparable to control PyCEN parasites. Thus, PvCEN plasmids were maintained throughout the parasite life cycle. We also validated several P. vivax promoter activities and showed that hsp70 promoter (~1 kb) was active throughout the parasite life cycle. This is the first data for the functional characterization of a P. vivax centromere that can be used in future P. vivax biological research.

Indexed as

AnimalsCentromereChromosome SegregationCulicidaeFemaleGreen Fluorescent ProteinsHumansMalaria, VivaxMiceMice, Inbred BALB CMice, Inbred ICRMicroorganisms, Genetically-ModifiedPlasmidsPlasmodium vivaxPlasmodium yoeliiPromoter Regions, GeneticGreen Fluorescent ProteinsTetrahydrofolate Dehydrogenase

Identifiers

PMID31860644
PMCPMC6924662
OpenAlexW2994750888

What OpenQuestion holds

Textmetadata
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.