RRC ID 47750
Author Nakai Y, Nakajima K, Robert J, Yaoita Y.
Title Ouro proteins are not essential to tail regression during Xenopus tropicalis metamorphosis.
Journal Genes Cells
Abstract Tail regression is one of the most prominent transformations observed during anuran metamorphosis. A tadpole tail that is twice as long as the tadpole trunk nearly disappears within 3 days in Xenopus tropicalis. Several years ago, it was proposed that this phenomenon is driven by an immunological rejection of larval-skin-specific antigens, Ouro proteins. We generated ouro-knockout tadpoles using the TALEN method to reexamine this immunological rejection model. Both the ouro1- and ouro2-knockout tadpoles expressed a very low level of mRNA transcribed from a targeted ouro gene, an undetectable level of Ouro protein encoded by a target gene and a scarcely detectable level of the other Ouro protein from the untargeted ouro gene in tail skin. Furthermore, congenital athymic frogs were produced by Foxn1 gene modification. Flow cytometry analysis showed that mutant frogs lacked splenic CD8(+) T cells, which play a major role in cytotoxic reaction. Furthermore, T-cell-dependent skin allograft rejection was dramatically impaired in mutant frogs. None of the knockout tadpoles showed any significant delay in the process of tail shortening during the climax of metamorphosis, which shows that Ouro proteins are not essential to tail regression at least in Xenopus tropicalis and argues against the immunological rejection model.
Volume 21(3)
Pages 275-86
Published 2016-3-1
DOI 10.1111/gtc.12337
PMID 26847415
PMC PMC4789143
MeSH Animals CD8-Positive T-Lymphocytes / metabolism Forkhead Transcription Factors / genetics Forkhead Transcription Factors / metabolism Gene Expression Regulation, Developmental Keratins / genetics Keratins / metabolism* Metamorphosis, Biological / genetics* Thymus Gland / cytology Thymus Gland / metabolism Xenopus Xenopus Proteins / genetics Xenopus Proteins / metabolism*
IF 1.655
Times Cited 7
Clawed frogs / Newts X. tropicalis