Nucleic Acids Research, 1983, Vol. 11, No. 6 1735-1746
© 1983
MOLECULAR BIOLOGY |
Mitochondria circular RN As are absent in sporulating cells of Saccharomyces cerevisiae
*Institut for Genetik und Mikrobiologie der Universtitat Maria-Wardstrasse la, 8000 Mflnchen 19, FRG Institut ftlr Allgemeine Biochemie und Ludwig-Boltzmann Forschungsstelle fur Biochemie Wahringerstrasse 38, 1090 Vienna, Austria
Received January 17, 1983. Accepted February 18, 1983.
During speculation of Saccharomyces cerevisiae the mitochondria undergo a differentiation process, leading to a "spore mitochondrion", which differs both physiologically and morphologically from vegetative cell mitochondria. We report here the behaviour of the mitochondrial transcripts during this differentiation process. The circular transcripts representing spliced introns of the two mitochondrial split genes for cytochrome b and for the subunit 1 of the cytochrome c oxidase, which are very abundant during vegetative growth, are not detectable in sporulating cells. This loss does neither take place in haploid cells under sporulation conditions nor when erythromycin is added to the medium. The process of some mRNAs is advanced in relation to their precursors in sporulating cells.