Nucleic Acids Research, 1992, Vol. 20, No. 7 1747-1754
© 1992
MOLECULAR BIOLOGY |
A maturase-encoding group MA intron of yeast mitochondria self-splices in vitro
Department of Molecular Genetics, The Ohio State University 484 W. 12th Avenue, Columbus, OH 43210 1Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd Dallas, TX 75345, USA
Received November 4, 1991. Revised February 20, 1992. Accepted February 20, 1992.
Intron 1 of the coxl gene of yeast mitochondrial DNA (al1) is a group HA intron that encodes a maturase function required for its splicing in vivo. It is shown here to self-splice in vitro under some reaction conditions reported earlier to yield efficient self-splicing of group IIB introns of yeast mtDNA that do not encode maturase functions. Unlike the group IIB introns, al1 is inactive in 10 mM Mg2+ (including spermidine) and requires much higher levels of Mg2+ and added salts (1M NH4CI or KCI or 2M (NH4)2SO4) for ready detection of splicing activity. In KCI-stimulated reactions, splicing occurs with little normal branch formation; a post-splicing reaction of linear excised intron RNA that forms shorter lariat RNAs with branches at cryptic sites was evident in those samples. At low levels of added NH4CI or KCI, the precursor RNA carries out the first reaction step but appears blocked in the splicing step. AM RNA is most reactive at 3742°C, as compared with 45°C for the group IIB Introns; and it lacks the KCl-or NH4CI-dependent spliced-exon reopening reaction that is evident for the self-splicing group IIB introns of yeast mitochondria. Like the group IIB intron al5
, the domain 4 of ah can be largely deleted in cis, without blocking splicing; also, frans-splicing of half molecules interrupted in domain 4 occurs. This is the first report of a maturase-encoding intron of either group I or group II that self-splices in vitro.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
N. Toor, A. R. Robart, J. Christianson, and S. Zimmerly Self-splicing of a group IIC intron: 5' exon recognition and alternative 5' splicing events implicate the stem-loop motif of a transcriptional terminator Nucleic Acids Res., December 2, 2006; 34(22): 6461 - 6471. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Mohr, M. Matsuura, P. S. Perlman, and A. M. Lambowitz A DEAD-box protein alone promotes group II intron splicing and reverse splicing by acting as an RNA chaperone PNAS, March 7, 2006; 103(10): 3569 - 3574. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. W. ODOM, D. L. SHENKENBERG, J. A. GARCIA, and D. L. HERRIN A horizontally acquired group II intron in the chloroplast psbA gene of a psychrophilic Chlamydomonas: In vitro self-splicing and genetic evidence for maturase activity RNA, July 1, 2004; 10(7): 1097 - 1107. [Abstract] [Full Text] [PDF] |
||||
![]() |
H.-R. Huang, M. Y. Chao, B. Armstrong, Y. Wang, A. M. Lambowitz, and P. S. Perlman The DIVa Maturase Binding Site in the Yeast Group II Intron aI2 Is Essential for Intron Homing but Not for In Vivo Splicing Mol. Cell. Biol., December 1, 2003; 23(23): 8809 - 8819. [Abstract] [Full Text] [PDF] |
||||



