RpS3 translation is repressed by interaction with its own mRNA

Hag Dong Kim, Tae Sung Kim, Yoo Jin Joo, Hyun Seock Shin, Sang Hwa Kim, Chang Young Jang, Cheol Eui Lee, Joon Kim

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Ribosomal protein S3 (RpS3) is a well-known multi-functional protein mainly involved in protein biosynthesis as a member of the small ribosomal subunit. It also plays a role in repairing various DNA damage acting as a repair UV endonuclease. Most of the rpS3 pool is located in the ribosome while the minority exists in free form in the cytoplasm. We here report an additional function of rpS3 in which it represses its own translation by binding to its cognate mRNA. Through RT-PCR of the RNAs co-immunoprecipitated with ectopically expressed rpS3, rpS3 protein was found to interact with various RNAs-endogenous rpS3, 18S rRNA. The S3-C terminal domain was shown to be the major mRNA binding domain of rpS3, independent of the KH domain. This interaction was shown to occur in cytoplasmic fractions rather than ribosomal fractions, and then is involved in its own mRNA translational inhibition by in vitro translation. Furthermore, when Flag-tagged rpS3 was transiently transfected into 293T cells, the level of endogenous rpS3 gradually decreased regardless of transcription. These results suggest that free rpS3 regulates its own translation via a feedback mechanism.

Original languageEnglish
Pages (from-to)294-303
Number of pages10
JournalJournal of Cellular Biochemistry
Volume110
Issue number2
DOIs
Publication statusPublished - 2010 May 15

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Keywords

  • KH domain
  • Monosome
  • Polysome
  • Ribosome
  • RpS3

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology

Cite this

Kim, H. D., Kim, T. S., Joo, Y. J., Shin, H. S., Kim, S. H., Jang, C. Y., Lee, C. E., & Kim, J. (2010). RpS3 translation is repressed by interaction with its own mRNA. Journal of Cellular Biochemistry, 110(2), 294-303. https://doi.org/10.1002/jcb.22537