ZFIN ID: ZDB-PUB-080908-13
WDR55 Is a Nucleolar Modulator of Ribosomal RNA Synthesis, Cell Cycle Progression, and Teleost Organ Development
Iwanami, N., Higuchi, T., Sasano, Y., Fujiwara, T., Hoa, V.Q., Okada, M., Talukder, S.R., Kunimatsu, S., Li, J., Saito, F., Bhattacharya, C., Matin, A., Sasaki, T., Shimizu, N., Mitani, H., Himmelbauer, H., Momoi, A., Kondoh, H., Furutani-Seiki, M., and Takahama, Y.
Date: 2008
Source: PLoS Genetics   4(8): e1000171 (Journal)
Registered Authors: Furutani-Seiki, Makoto, Kondoh, Hisato
Keywords: Thymus, Embryos, Ribosomal RNA, Zebrafish, Cell cycle and cell division, Nucleolus, Point mutation, Complementary DNA
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Cell Cycle*
  • Cell Nucleolus/genetics
  • Cell Nucleolus/metabolism
  • Fish Proteins/genetics
  • Fish Proteins/metabolism*
  • Mice
  • Mice, Knockout
  • Molecular Sequence Data
  • Mutation, Missense
  • NIH 3T3 Cells
  • Nuclear Proteins/genetics
  • Nuclear Proteins/metabolism*
  • Oryzias/genetics
  • Oryzias/growth & development*
  • Oryzias/metabolism*
  • Phenotype
  • RNA Processing, Post-Transcriptional
  • RNA, Ribosomal/biosynthesis*
  • RNA, Ribosomal/genetics
  • Sequence Alignment
  • Thymus Gland/growth & development*
  • Thymus Gland/metabolism
  • Zebrafish/genetics
  • Zebrafish/growth & development
  • Zebrafish/metabolism
PubMed: 18769712 Full text @ PLoS Genet.
The thymus is a vertebrate-specific organ where T lymphocytes are generated. Genetic programs that lead to thymus development are incompletely understood. We previously screened ethylnitrosourea-induced medaka mutants for recessive defects in thymus development. Here we report that one of those mutants is caused by a missense mutation in a gene encoding the previously uncharacterized protein WDR55 carrying the tryptophan-aspartate-repeat motif. We find that WDR55 is a novel nucleolar protein involved in the production of ribosomal RNA (rRNA). Defects in WDR55 cause aberrant accumulation of rRNA intermediates and cell cycle arrest. A mutation in WDR55 in zebrafish also leads to analogous defects in thymus development, whereas WDR55-null mice are lethal before implantation. These results indicate that WDR55 is a nuclear modulator of rRNA synthesis, cell cycle progression, and embryonic organogenesis including teleost thymus development.