Leishmania pp 141-167 | Cite as

Cos-Seq: A High-Throughput Gain-of-Function Screen for Drug Resistance Studies in Leishmania

  • Jade-Eva Potvin
  • Philippe Leprohon
  • Elodie Gazanion
  • Mansi Sharma
  • Christopher Fernandez-Prada
  • Marc OuelletteEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1971)


Leishmania is still a major cause of mortality and morbidity worldwide. Few efficient drugs are available, and resistance threatens actual treatments. In order to improve knowledge about the mode of action of current drugs and those in development, as well as to understand the mechanisms pertaining to their resistance, we recently described a sensitive and high-throughput method termed Cos-Seq. Here we provide a detailed protocol for every step of the procedure, from library construction to drug selection, cosmid extraction, and next-generation sequencing of extracted cosmids. A section on the bioinformatics of Cos-Seq is also included. Cos-Seq facilitates the identification of gain-of-function resistance mechanisms and drug targets and is a useful tool in resistance and drug development studies.

Key words

Leishmania Next-generation sequencing Cos-Seq Drug resistance Mode of action 


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Jade-Eva Potvin
    • 1
  • Philippe Leprohon
    • 1
  • Elodie Gazanion
    • 2
  • Mansi Sharma
    • 1
  • Christopher Fernandez-Prada
    • 3
  • Marc Ouellette
    • 1
    Email author
  1. 1.Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Centre de Recherche en Infectiologie du Centre de Recherche du CHU de QuébecUniversité LavalQuébecCanada
  2. 2.Université de Montpellier, IRD, CNRS, MIVEGECMontpellierFrance
  3. 3.Département de Pathologie et Microbiologie, Faculté de Médecine VétérinaireUniversité de MontréalSaint-HyacintheCanada

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