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Involvement of Rel/NF‐κB in regulation of ascidian notochord formation
Author(s) -
Shimada Masumi,
Satoh Noriyuki,
Yokosawa Hideyoshi
Publication year - 2001
Publication title -
development, growth and differentiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.864
H-Index - 66
eISSN - 1440-169X
pISSN - 0012-1592
DOI - 10.1046/j.1440-169x.2001.00560.x
Subject(s) - notochord , biology , messenger rna , microbiology and biotechnology , complementary dna , nuclear protein , embryo , transcription factor , embryogenesis , gene , genetics
The Rel/NF‐κB family is known to be involved in a wide variety of biological processes, including morphogenesis. In the present study, two protochordate cDNA clones encoding Rel/NF‐κB proteins, named As‐rel1 and As‐rel2 , were isolated from a fertilized egg cDNA library of the ascidian Halocynthia roretzi . The As‐rel1 protein is a typical Rel/NF‐κB family member, containing a Rel homology domain, a nuclear localization sequence and a C‐terminal putative transcription activation domain, while the As‐rel2 protein is a novel Rel/NF‐κB family member that lacks a nuclear localization sequence and the C‐terminal domain. Northern blot analyses showed that both transcripts were maternally expressed and that their expression changed during development of H. roretzi embryos. Although injection of the As‐rel2 mRNA into H. roretzi fertilized eggs had little effect on embryonic development, injection of the As‐rel1 mRNA interfered greatly with notochord formation, resulting in a shortened tail with a reduced number of notochord cells. In contrast, embryos co‐injected with As‐rel1 and As‐rel2 mRNA developed normally, indicating that the As‐rel2 protein rescued the defect in notochord formation induced by the injection of As‐rel1 mRNA alone. These results strongly suggest that the As‐rel1 protein functions as a suppressor in ascidian notochord formation, while the As‐rel2 protein has an antagonistic effect on the action of the As‐rel1 protein.