In:
PLOS Genetics, Public Library of Science (PLoS), Vol. 17, No. 3 ( 2021-3-29), p. e1009466-
Abstract:
Planarians are flatworms and can perform whole-body regeneration. This ability involves a mechanism to distinguish between anterior-facing wounds that require head regeneration and posterior-facing wounds that require tail regeneration. How this head-tail regeneration polarity decision is made is studied to identify principles underlying tissue-identity specification in regeneration. We report that inhibition of activin-2 , which encodes an Activin-like signaling ligand, resulted in the regeneration of ectopic posterior-facing heads following amputation. During tissue turnover in uninjured planarians, positional information is constitutively expressed in muscle to maintain proper patterning. Positional information includes Wnts expressed in the posterior and Wnt antagonists expressed in the anterior. Upon amputation, several wound-induced genes promote re-establishment of positional information. The head-versus-tail regeneration decision involves preferential wound induction of the Wnt antagonist notum at anterior-facing over posterior-facing wounds. Asymmetric activation of notum represents the earliest known molecular distinction between head and tail regeneration, yet how it occurs is unknown. activin-2 RNAi animals displayed symmetric wound-induced activation of notum at anterior- and posterior-facing wounds, providing a molecular explanation for their ectopic posterior-head phenotype. activin-2 RNAi animals also displayed anterior-posterior (AP) axis splitting, with two heads appearing in anterior blastemas, and various combinations of heads and tails appearing in posterior blastemas. This was associated with ectopic nucleation of anterior poles, which are head-tip muscle cells that facilitate AP and medial-lateral (ML) pattern at posterior-facing wounds. These findings reveal a role for Activin signaling in determining the outcome of AP-axis-patterning events that are specific to regeneration.
Type of Medium:
Online Resource
ISSN:
1553-7404
DOI:
10.1371/journal.pgen.1009466
DOI:
10.1371/journal.pgen.1009466.g001
DOI:
10.1371/journal.pgen.1009466.g002
DOI:
10.1371/journal.pgen.1009466.g003
DOI:
10.1371/journal.pgen.1009466.g004
DOI:
10.1371/journal.pgen.1009466.g005
DOI:
10.1371/journal.pgen.1009466.g006
DOI:
10.1371/journal.pgen.1009466.g007
DOI:
10.1371/journal.pgen.1009466.s001
DOI:
10.1371/journal.pgen.1009466.s002
DOI:
10.1371/journal.pgen.1009466.s003
DOI:
10.1371/journal.pgen.1009466.s004
DOI:
10.1371/journal.pgen.1009466.s005
DOI:
10.1371/journal.pgen.1009466.s006
DOI:
10.1371/journal.pgen.1009466.s007
DOI:
10.1371/journal.pgen.1009466.s008
DOI:
10.1371/journal.pgen.1009466.s009
DOI:
10.1371/journal.pgen.1009466.s010
DOI:
10.1371/journal.pgen.1009466.s011
DOI:
10.1371/journal.pgen.1009466.s012
DOI:
10.1371/journal.pgen.1009466.s013
DOI:
10.1371/journal.pgen.1009466.r001
DOI:
10.1371/journal.pgen.1009466.r002
DOI:
10.1371/journal.pgen.1009466.r003
DOI:
10.1371/journal.pgen.1009466.r004
DOI:
10.1371/journal.pgen.1009466.r005
DOI:
10.1371/journal.pgen.1009466.r006
Language:
English
Publisher:
Public Library of Science (PLoS)
Publication Date:
2021
detail.hit.zdb_id:
2186725-2
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