RRC ID 47282
Author Ikeda T, Satou Y.
Title Differential temporal control of Foxa.a and Zic-r.b specifies brain versus notochord fate in the ascidian embryo.
Journal Development
Abstract In embryos of an invertebrate chordate, Ciona intestinalis, two transcription factors, Foxa.a and Zic-r.b, are required for specification of the brain and the notochord, which are derived from distinct cell lineages. In the brain lineage, Foxa.a and Zic-r.b are expressed with no temporal overlap. In the notochord lineage, Foxa.a and Zic-r.b are expressed simultaneously. In the present study, we found that the temporally non-overlapping expression of Foxa.a and Zic-r.b in the brain lineage was regulated by three repressors: Prdm1-r.a (formerly called BZ1), Prdm1-r.b (BZ2) and Hes.a. In morphant embryos of these three repressor genes, Foxa.a expression was not terminated at the normal time, and Zic-r.b was precociously expressed. Consequently, Foxa.a and Zic-r.b were expressed simultaneously, which led to ectopic activation of Brachyury and its downstream pathways for notochord differentiation. Thus, temporal controls by transcriptional repressors are essential for specification of the two distinct fates of brain and notochord by Foxa.a and Zic-r.b Such a mechanism might enable the repeated use of a limited repertoire of transcription factors in developmental gene regulatory networks.
Volume 144(1)
Pages 38-43
Published 2017-1-1
DOI 10.1242/dev.142174
PII dev.142174
PMID 27888196
MeSH Animals Animals, Genetically Modified Body Patterning / genetics Brain / embryology* Brain / metabolism Cell Differentiation / genetics Ciona intestinalis / embryology* Ciona intestinalis / genetics* Embryo, Nonmammalian Forkhead Transcription Factors / genetics* Gene Expression Regulation, Developmental Homeodomain Proteins / genetics* Notochord / embryology* Notochord / metabolism Urochordata / embryology Urochordata / genetics
IF 5.611
Times Cited 8
C.intestinalis / (O.japonicus) Wild C. int