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oai:www.ideals.illinois.edu:2142/20815 2023-07-10 col_2142_5131 col_2142_14826 com_2142_5130 com_2142_8913 com_2142_8903

Laughnan, John R. Leja, Carol Ann 2011-05-07T12:50:07Z 2011-05-07T12:50:07Z 10000-01-01 1991 The loss of $\sigma\sp\prime$ and $\psi\sp\prime$ termini of linear molecules was found to be a general characteristic of cytoplasmic reversion for all the nuclear-cytoplasmic genomic backgrounds examined in cms-S maize. Those cytoplasmic revertants that lose S1 and S2 lose $\sigma\sp\prime$ and $\psi\sp\prime$ termini by recombination with $\sigma$ and $\psi$ regions of the main mitochondrial genome to generate internal junction sequences of $\sigma$-$\sigma\sp\prime$, $\psi$-$\sigma\sp\prime$, $\sigma$-$\psi\sp\prime$, and $\psi$-$\psi\sp\prime$, thereby circularizing the mitochondrial genome. However, which internal junction sequences are generated appear to be influenced by the nuclear genotype. Cytoplasmic revertants that retain S1 and S2, namely those in the WF9 nuclear background, differ in the organization of their mitochondrial genome from those cytoplasmic revertants that lose S1 and S2. Although some data provide evidence for the loss of $\sigma\sp\prime$ and $\psi\sp\prime$ termini by recombination with $\psi$ in these revertants, the continued presence of termini of linear molecules having $\sigma$/$\psi$ adjacent to a terminal S1/S2 and the presence of altered $\sigma\sp\prime$/$\psi\sp\prime$ termini suggest that circularization of the mitochondrial genome does not accompany cytoplasmic reversion in the WF9 nuclear background. Since S1 and S2 continue to be present after cytoplasmic reversion in the WF9 nuclear background, loss or mutation of $\sigma\sp\prime$ and $\psi\sp\prime$ termini and of $\sigma$-R and $\psi$-R junctions may be a way to stabilize the organization of the mitochondrial genome as linear molecules. The 2 kb sequence common to $\sigma\sp\prime$ and $\psi\sp\prime$ appears to result in the production of sterile-specific transcripts. Made available in DSpace on 2011-05-07T12:50:07Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136654.pdf: 16040682 bytes, checksum: 34fb1a5127590dec3f02fa2236c1a59c (MD5) Previous issue date: 1991 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:46:28Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:20:50-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9136654 (UMI)AAI9136654 http://hdl.handle.net/2142/20815 eng Copyright 1991 Leja, Carol Ann Biology, Molecular Organization and expression of the mitochondrial genome in cytoplasmic revertants ofcms-S maize text Biology Biology University of Illinois at Urbana-Champaign Dissertation Ph.D.