Group II introns are widespread in plant cell organelles []. In vivo, most plant group II introns do not self-splice, but require the assistance of proteinaceous splicing factors, known as maturases. In higher plants, maturases are encoded for in the nuclear genes [], but are otherwise encoded by organellar introns. This entry represents maturase K, which is usually encoded in the trnK tRNA gene intron, and probably assists in splicing its own and other chloroplast group II introns.
Group II introns are widespread in plant cell organelles []. In vivo, most plant group II introns do not self-splice, but require the assistance of proteinaceous splicing factors, known as maturases. In higher plants, maturases are encoded for in the nuclear genes [], but are otherwise encoded by organellar introns. Maturase MatK is usually encoded in the trnK tRNA gene intron, and probably assists in splicing its own and other chloroplast group II introns.The N-terminal domain of MatK appears to be a divergent reverse transcriptase domain that has lost most of the conserved sequence motifs typical of functional reverse transcriptases []. The function of this domain is not known, but it may be important in RNA splicing.