Deduced primary structure of a Xenopus proteasome subunit XC3 and expression of its mRNA during early development

Gen Fujii, Kosuke Tashiro, Yasufumi Emori, Kaoru Saigo, Keiji Tanaka, Koichiro Shiokawa

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21 Citations (Scopus)


Proteasome is a non-lysosomal proteinase complex ubiquitously distributed in eukaryotic cells. We isolated here the cDNA clone for one of the proteasome subunits (XC3) from Xenopus ovary cDNA libraries using rat RC3 cDNA as a prove. The cDNA is 885 bp long and encodes 234 amino acids. The deduced amino acid sequence is highly homologous (95.3%) to those of rat RC3 and human HC3 subunits. The cDNA for XC3 is one of the maternal mRNAs and detected at all the embryonic stages investigated, but its level changes in a characteristic way especlally at the gastrula stage. We suggest that the highly conserved XC3 subunit plays an essential role in proteasome function and also that during Xenopus embryogenesis mRNA for XC3 subunit is replaced from maternal to newly-synthesized one probably around the gastrula stage.

Original languageEnglish
Pages (from-to)1233-1239
Number of pages7
JournalBiochemical and Biophysical Research Communications
Issue number3
Publication statusPublished - Aug 15 1991
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

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