@article {40,
	title = {A trans-splicing group I intron and tRNA-hyperediting in the mitochondrial genome of the lycophyte Isoetes engelmannii},
	journal = {Nucleic Acids Research},
	volume = {37},
	year = {2009},
	note = {Cited By (since 1996):40Export Date: 11 November 2013Source: Scopus},
	month = {2009///},
	pages = {5093 - 5104},
	abstract = {Plant mitochondrial genomes show much more evolutionary plasticity than those of animals. We analysed the first mitochondrial DNA (mtDNA) of a lycophyte, the quillwort Isoetes engelmannii, which is separated from seed plants by more than 350 million years of evolution. The Isoetes mtDNA is particularly rich in recombination events, and chloroplast as well as nuclear DNA inserts document the incorporation of foreign sequences already in this most ancestral vascular plant lineage. On the other hand, particularly small group II introns and short intergenic regions reveal a tendency of evolution towards a compact mitochondrial genome. RNA editing reaches extreme levels exceeding 100 pyrimidine exchanges in individual mRNAs and, hitherto unobserved in such frequency, also in tRNAs with 18 C-to-U conversions in the tRNA for proline. In total, some 1500 sites of RNA editing can be expected for the Isoetes mitochondrial transcriptome. As a unique molecular novelty, the Isoetes cox 1 gene requires trans-splicing via a discontinuous group I intron demonstrating disrupted, but functional, RNAs for yet another class of natural ribozymes. {\textcopyright} 2009 The Author(s).},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-69849093397\&partnerID=40\&md5=b046c2a9f2f25d1f22409335cffd8762},
	author = {Grewe, F. and Viehoever, P. and Weisshaar, B. and Knoop, V.}
}
@article {27,
	title = {A unique transcriptome: 1782 positions of RNA editing alter 1406 codon identities in mitochondrial mRNAs of the lycophyte Isoetes engelmannii},
	journal = {Nucleic Acids Research},
	volume = {39},
	year = {2011},
	note = {Cited By (since 1996):22Export Date: 11 November 2013Source: Scopus},
	month = {2011///},
	pages = {2890 - 2902},
	abstract = {The analysis of the mitochondrial DNA of Isoetes engelmannii as a first representative of the lycophytes recently revealed very small introns and indications for extremely frequent RNA editing. To analyze functionality of intron splicing and the extent of RNA editing in I. engelmannii, we performed a comprehensive analysis of its mitochondrial transcriptome. All 30 groups I and II introns were found to be correctly removed, showing that intron size reduction does not impede splicing. We find that mRNA editing affects 1782 sites, which lead to a total of 1406 changes in codon meanings. This includes the removal of stop codons from 23 of the 25 mitochondrial protein encoding genes. Comprehensive sequence analysis of multiple cDNAs per locus allowed classification of partially edited sites as either inefficiently edited but relevant or as non-specifically edited at mostly low frequencies. Abundant RNA editing was also found to affect tRNAs in hitherto unseen frequency, taking place at 41 positions in tRNA-precursors, including the first identification of U-to-C exchanges in two tRNA species. We finally investigated the four group II introns of the nad7 gene and could identify 27 sites of editing, most of which improve base pairing for proper secondary structure formation. {\textcopyright} 2011 The Author(s).},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-79954584259\&partnerID=40\&md5=1ca877f1fb310d7057203384afd34680},
	author = {Grewe, F. and Herres, S. and Vieh{\"o}ver, P. and Polsakiewicz, M. and Weisshaar, B. and Knoop, V.}
}
