Archaeal pre-mRNA splicing: A connection to hetero-oligomeric splicing endonuclease

• Published in: Biochemical and biophysical research communications Vol. 346; no. 3; pp. 1024 - 1032
• Main Authors: Yoshinari, Shigeo, Itoh, Takashi, Hallam, Steven J., DeLong, Edward F., Yokobori, Shin-ichi, Yamagishi, Akihiko, Oshima, Tairo, Kita, Kiyoshi, Watanabe, Yoh-ichi
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 04.08.2006
• Subjects: Aeropyrum pernix; Amino Acid Sequence; Archaea; Archaeal Proteins - genetics; Archaeal Proteins - metabolism; Base Sequence; Bulge-helix-bulge motif; cbf5; Endoribonucleases - metabolism; Intron; Introns - genetics; Molecular Sequence Data; Nucleic Acid Conformation; Pre-mRNA splicing; Protein Biosynthesis - genetics; RNA Precursors - chemistry; RNA Precursors - genetics; RNA Precursors - metabolism; RNA Splicing - genetics; RNA, Archaeal - chemistry; RNA, Archaeal - genetics; RNA, Archaeal - metabolism; Splicing endonuclease; Sulfolobus - chemistry; Sulfolobus - enzymology; Sulfolobus - genetics; Sulfolobus solfataricus; cbf5; Splicing endonuclease; Pre-mRNA splicing; Intron; Archaea; Bulge-helix-bulge motif
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2006.06.011

Eukaryotic Cbf5 is a protein subunit of the small nucleolar RNA–protein complex. Previously, we identified, in archaeal homologs of cbf5 of the crenarchaea, Aeropyrum pernix, Sulfolobus solfataricus, and Sulfolobus tokodaii, the first examples of introns of archaeal protein-coding genes. Here, we report the immunological detection of Cbf5 protein of S. tokodaii, the product of the spliced cbf5 mRNA. The hetero-oligomeric splicing endonuclease activity from recombinant S. tokodaii subunits cleaved at the exon-intron boundaries of cbf5 pre-mRNA fragments,suggesting that synthesis of full-length Cbf5 protein requires this activity. Database searches and PCR screens identified additional cbf5 introns in some, but not all sequenced crenarchaeal genomes. The predicted secondary structures of exon-intron boundaries of many of the newly identified intron-containing cbf5 pre-mRNAs contained relaxed forms of the bulge-helix-bulge motif similar to that of S. tokodaii. These observations are consistent with previous reports indicating that subunit composition of the splicing endonuclease contributes to substrate specificity.