Table 1.
Gene Expression Analysis on the sta1 Mutant Backgrounda
| Processb | Protein/Genec | Proven/Assumed Function | Protein Localization |
Reference | Transcript Levels in sta1 vs. Wild Typed |
|---|---|---|---|---|---|
| Oxidative stress | Apx1 | H2O2 scavenging | Cytosol | Kubo et al. (1993) | ⩽2↑ |
| Cu/ZnSOD | O2·− scavenging | Cytosol | Kliebenstein et al. (1998) | 2↑ | |
| Cu/ZnSOD | O2·− scavenging | Plastids | Kliebenstein et al. (1998) | 2↑ | |
| FeSOD | O2·− scavenging | Plastids | Kliebenstein et al. (1998) | WT | |
| MnSOD | O2·− scavenging | Mitochondria | Kliebenstein et al. (1998) | WT | |
| P1 | NADPH oxidoreductase | Cytosol | Babiychuk et al. (1995) | WT | |
| Senescence | Cat3 | H2O2 scavenging | Peroxisomes | Park et al. (1998) | WT |
| Sag12 | Proteolysis (?) | (?) | Lohman et al. (1994) | ND | |
| Iron homeostasis | Ferritin | Iron storage | Plastids | Gaymard et al. (1996) | WT |
| Pathogen response | PR1 | (?) | (?) | Chen et al. (1993) | WT |
| Oxidative stress/ thermogenesis |
Alternative oxidase Aox1 Alternative oxidase Aox2a |
CN-resistant respiration CN-resistant respiration |
Mitochondria Mitochondria |
Saisho et al. (1997) Saisho et al. (1997) |
WT ND |
| Fe/S cluster biogenesis | Nfs1p-like | l-cysteine desulfurase (?) | Mitochondria | This work | 2↑ |
| Sta2 | ABC transporter | Mitochondria | This work | WT | |
| Branched-chain amino acid synthesis (?) |
Bat1p-like | Transaminase; suppressor of atm1 mutation |
(?) | Kispal et al. (1996) | 2↑ |
| DNA repair/recombination | Zap | Poly(ADP-ribos)ylation | Nucleus | Babiychuk et al. (1998) | 2–3↑ |
| App | Poly(ADP-ribos)ylation | Nucleus | Babiychuk et al. (1998) | 6–10↑ | |
| AtRad51 | DNA strand exchange | Nucleus | Doutriaux et al. (1998) | 4–6↑ |
Transcript levels were measured in the wild type and sta1 by using RNA gel blot hybridization with radioactively labeled DNA probes and quantification of the hybridization signal on a phosphorimaging device. Total RNA was extracted from in vitro–grown plants; developmental defects of sta1 are most pronounced under these conditions (see Methods for details). (?) indicates cases in which function, intracellular localization of protein, or the process in which it is involved is not known or proven formally.
Although the process in which the analyzed genes are involved is indicated, this grouping does not mean necessarily that genes belong to the same regulon.
DNA probes were prepared from cDNAs. APX1, all of SODs, P1, ZAP, and APP cDNAs were from a collection of the Department of Plant Genetics (Ghent University, Belgium); Nfs and STA2 were amplified by PCR in this study; CAT3, ferritin, Bat1p-like, and PR1 cDNAs reported as expressed sequence tag markers in public databases were provided by the Ohio Arabidopsis Stock Center (Columbus); all clones were confirmed by partial DNA sequencing. Clones SAG12, AOX1 and AOX2a, and AtRAD51 were generous gifts of Richard Amasino, Mikio Nakazono, and Florence Couteau, respectively.
Relative to the wild type, the upregulation (↑) of the gene is indicated as fold; a steady state level of expression that did not exceed a twofold difference with the wild type is indicated by WT; ND, no transcript was detected both in the wild type and sta1.