The chloroplast chlL gene of the green alga Chlorella vulgaris C-27 contains a self-splicing group I intron.

Abstract

The chlL gene product is involved in the light-independent synthesis of chlorophyll in photosynthetic bacteria, green algae and non-flowering plants. The chloroplast genome of Chlorella vulgaris strain C-27 contains the first example of a split chlL gene, which is interrupted by 951 bp group I intron in the coding region. In vitro synthesized pre-mRNA containing the entire intron and parts of the flanking exon sequence is able to efficiently self-splice in vitro in the presence of a divalent and a monovalent cation and GTP, to yield the ligated exons and other splicing intermediates characteristic of self-splicing group I introns. The 5' and 3' splice sites were confirmed by cDNA sequencing and the products of the splicing reaction were characterized by primer extension analysis. The absence of a significant ORF in the long P9 region (522 nt), separating the catalytic core from the 3' splice site, makes this intron different from the other known examples of group I introns. Guanosine-mediated attack at the 3' splice site and the presence of G-exchange reaction sites internal to the intron are some other properties demonstrated for the first time by an intron of a protein-coding plastid gene.

• Authors: M Kapoor, T Wakasugi, K Yoshinaga, M Sugiura
• Journal: Molecular & general genetics : MGG (Mol Gen Genet) Vol. 250 Issue 6 Pg. 655-64 (Apr 10 1996) ISSN: 0026-8925 [Print] Germany
• PMID: 8628225 (Publication Type: Journal Article)

Chemical References

• DNA Primers
• Proteins
• RNA Precursors
• Chlorophyll
• Guanosine Triphosphate

Topics

• Amino Acid Sequence
• Base Sequence
• Binding Sites
• Chlorella (chemistry, genetics)
• Chlorophyll (biosynthesis)
• Chloroplasts (chemistry, genetics)
• Conserved Sequence
• DNA Primers
• Electrophoresis, Polyacrylamide Gel
• Genes
• Guanosine Triphosphate (metabolism)
• Introns (genetics)
• Molecular Sequence Data
• Nucleic Acid Conformation
• Open Reading Frames (genetics)
• Proteins (chemistry, genetics)
• RNA Precursors (chemistry, metabolism)
• RNA Splicing (genetics)
• Sequence Homology, Nucleic Acid