1. Cell Biology
  2. Developmental Biology
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Relish plays a dynamic role in the niche to modulate Drosophila blood progenitor homeostasis in development and infection

  1. Parvathy Ramesh
  2. Nidhi Sharma Dey
  3. Aditya Kanwal
  4. Sudip Mandal
  5. Lolitika Mandal  Is a corresponding author
  1. Indian Institute of Science Education and Research Mohali, India
Research Article
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Cite this article as: eLife 2021;10:e67158 doi: 10.7554/eLife.67158

Abstract

Immune challenges demand the gearing up of basal hematopoiesis to combat infection. Little is known about how during development, this switch is achieved to take care of the insult. Here, we show that the hematopoietic niche of the larval lymph gland of Drosophila senses immune challenge and reacts to it quickly through the nuclear factor-κB (NF-κB), Relish, a component of the immune deficiency (Imd) pathway. During development, Relish is triggered by ecdysone signaling in the hematopoietic niche to maintain the blood progenitors. Loss of Relish causes an alteration in the cytoskeletal architecture of the niche cells in a Jun Kinase dependent manner, resulting in the trapping of Hh implicated in progenitor maintenance. Notably, during infection, downregulation of Relish in the niche tilts the maintenance program towards precocious differentiation, thereby bolstering the cellular arm of the immune response.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1- 7 and their respective supplemental figures.

Article and author information

Author details

  1. Parvathy Ramesh

    Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, India
    Competing interests
    The authors declare that no competing interests exist.
  2. Nidhi Sharma Dey

    Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, India
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9432-0221
  3. Aditya Kanwal

    Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, India
    Competing interests
    The authors declare that no competing interests exist.
  4. Sudip Mandal

    Molecular Cell and Developmental Biology Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, India
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2211-483X
  5. Lolitika Mandal

    Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Mohali, India
    For correspondence
    lolitika@iisermohali.ac.in
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7711-6090

Funding

DBT Wellcome Trust India Alliance (IA/S/17/503100)

  • Lolitika Mandal

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Bruno Lemaître, École Polytechnique Fédérale de Lausanne, Switzerland

Publication history

  1. Received: February 2, 2021
  2. Accepted: July 14, 2021
  3. Accepted Manuscript published: July 22, 2021 (version 1)

Copyright

© 2021, Ramesh et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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