Mutation at the chlamydomonas nuclear NAC2 locus specifically affects stability of the chloroplast psbD transcript encoding polypeptide D2 of PS II
The nuclear NAC2 locus of C. reinhardtii encodes a trans-acting factor that confers stability on the chloroplast message for the D2 protein of photosystem II (PS II). A mutant that carries a lesion in the NAC2 gene is unable to accumulate the psbD transcript encoding D2, but synthesizes all other PS...
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Published in | Cell Vol. 58; no. 5; pp. 869 - 876 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Cambridge, MA
Elsevier Inc
08.09.1989
Cell Press |
Subjects | |
Online Access | Get full text |
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Summary: | The nuclear
NAC2 locus of C. reinhardtii encodes a
trans-acting factor that confers stability on the chloroplast message for the D2 protein of photosystem II (PS II). A mutant that carries a lesion in the
NAC2 gene is unable to accumulate the
psbD transcript encoding D2, but synthesizes all other PS II proteins normally. However, the PS II complex is completely unstable in the
nac2–26 mutant, and all major PS II polypeptides, including the three oxygen-evolving enhancing proteins, are absent or greatly reduced in this strain because of posttranslational degradation. In C. reinhardtii the second exon of the
trans-spliced
psaA mRNA is cotranscribed with
psbD (Choquet et al., 1988), but the
nac2–26 mutation normally has no effect on
psaA message maturation or stability. However, in double mutants carrying the
nac2–26 mutation, as well as a mutation that prevents
psaA splicing, splicing intermediates carrying
psbD sequences are degraded. These results suggest that the
NAC2 gene product acts in a very specific manner to control the half-life of
psbD transcripts. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0092-8674 1097-4172 |
DOI: | 10.1016/0092-8674(89)90939-2 |