Details
| Original language | English |
|---|---|
| Pages (from-to) | 990-1001 |
| Number of pages | 12 |
| Journal | Biochimica et Biophysica Acta - Bioenergetics |
| Volume | 1817 |
| Issue number | 7 |
| Publication status | Published - 18 Apr 2012 |
Abstract
We studied the role of cytochrome c (CYTc), which mediates electron transfer between Complexes III and IV, in cellular events related with mitochondrial respiration, plant development and redox homeostasis. We analyzed single and double homozygous mutants in both CYTc-encoding genes from Arabidopsis: CYTC-1 and CYTC-2. While individual mutants were similar to wild-type, knock-out of both genes produced an arrest of embryo development, showing that CYTc function is essential at early stages of plant development. Mutants in which CYTc levels were extremely reduced respective to wild-type had smaller rosettes with a pronounced decrease in parenchymatic cell size and an overall delay in development. Mitochondria from these mutants had lower respiration rates and a relative increase in alternative respiration. Furthermore, the decrease in CYTc severely affected the activity and the amount of Complex IV, without affecting Complexes I and III. Reactive oxygen species levels were reduced in these mutants, which showed induction of genes encoding antioxidant enzymes. Ascorbic acid levels were not affected, suggesting that a small amount of CYTc is enough to support its normal synthesis. We postulate that, in addition to its role as an electron carrier between Complexes III and IV, CYTc influences Complex IV levels in plants, probably reflecting a role of this protein in Complex IV stability. This double function of CYTc most likely explains why it is essential for plant survival.
Keywords
- Arabidopsis thaliana, Cytochrome c, Embryo lethal, Mitochondrion, Respiratory chain complex
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Biophysics
- Biochemistry, Genetics and Molecular Biology(all)
- Biochemistry
- Biochemistry, Genetics and Molecular Biology(all)
- Cell Biology
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In: Biochimica et Biophysica Acta - Bioenergetics, Vol. 1817, No. 7, 18.04.2012, p. 990-1001.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Lack of cytochrome c in Arabidopsis decreases stability of Complex IV and modifies redox metabolism without affecting Complexes i and III
AU - Welchen, Elina
AU - Hildebrandt, Tatjana M.
AU - Lewejohann, Dagmar
AU - Gonzalez, Daniel H.
AU - Braun, Hans Peter
N1 - Funding information: We gratefully acknowledge Dr. Géraldine Bonnard (IBMP-CNRS, Strasbourg, France) for her collaboration during initial stages of this work under the cooperative project SECYT-ECOS (A03B04). We also acknowledge Dr. Eduardo Zabaleta (IIB, Mar del Plata, Argentina) for the gift of carbonic anhydrase antibodies and Dr. Raul Comelli for the development of COX2 antibodies. This project was supported by grants from CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas) , ANPCyT (Agencia Nacional de Promoción Científica y Tecnológica) , and UNL (Universidad Nacional del Litoral) . EW and DHG are members of CONICET and UNL. PostDoc stipend to EW to perform a relevant part of this work in the laboratory of HPB at Hannover University, was supported by the Deutsche Akademische Austauschdienst (DAAD) .
PY - 2012/4/18
Y1 - 2012/4/18
N2 - We studied the role of cytochrome c (CYTc), which mediates electron transfer between Complexes III and IV, in cellular events related with mitochondrial respiration, plant development and redox homeostasis. We analyzed single and double homozygous mutants in both CYTc-encoding genes from Arabidopsis: CYTC-1 and CYTC-2. While individual mutants were similar to wild-type, knock-out of both genes produced an arrest of embryo development, showing that CYTc function is essential at early stages of plant development. Mutants in which CYTc levels were extremely reduced respective to wild-type had smaller rosettes with a pronounced decrease in parenchymatic cell size and an overall delay in development. Mitochondria from these mutants had lower respiration rates and a relative increase in alternative respiration. Furthermore, the decrease in CYTc severely affected the activity and the amount of Complex IV, without affecting Complexes I and III. Reactive oxygen species levels were reduced in these mutants, which showed induction of genes encoding antioxidant enzymes. Ascorbic acid levels were not affected, suggesting that a small amount of CYTc is enough to support its normal synthesis. We postulate that, in addition to its role as an electron carrier between Complexes III and IV, CYTc influences Complex IV levels in plants, probably reflecting a role of this protein in Complex IV stability. This double function of CYTc most likely explains why it is essential for plant survival.
AB - We studied the role of cytochrome c (CYTc), which mediates electron transfer between Complexes III and IV, in cellular events related with mitochondrial respiration, plant development and redox homeostasis. We analyzed single and double homozygous mutants in both CYTc-encoding genes from Arabidopsis: CYTC-1 and CYTC-2. While individual mutants were similar to wild-type, knock-out of both genes produced an arrest of embryo development, showing that CYTc function is essential at early stages of plant development. Mutants in which CYTc levels were extremely reduced respective to wild-type had smaller rosettes with a pronounced decrease in parenchymatic cell size and an overall delay in development. Mitochondria from these mutants had lower respiration rates and a relative increase in alternative respiration. Furthermore, the decrease in CYTc severely affected the activity and the amount of Complex IV, without affecting Complexes I and III. Reactive oxygen species levels were reduced in these mutants, which showed induction of genes encoding antioxidant enzymes. Ascorbic acid levels were not affected, suggesting that a small amount of CYTc is enough to support its normal synthesis. We postulate that, in addition to its role as an electron carrier between Complexes III and IV, CYTc influences Complex IV levels in plants, probably reflecting a role of this protein in Complex IV stability. This double function of CYTc most likely explains why it is essential for plant survival.
KW - Arabidopsis thaliana
KW - Cytochrome c
KW - Embryo lethal
KW - Mitochondrion
KW - Respiratory chain complex
UR - http://www.scopus.com/inward/record.url?scp=84860794562&partnerID=8YFLogxK
U2 - 10.1016/j.bbabio.2012.04.008
DO - 10.1016/j.bbabio.2012.04.008
M3 - Article
C2 - 22551905
AN - SCOPUS:84860794562
VL - 1817
SP - 990
EP - 1001
JO - Biochimica et Biophysica Acta - Bioenergetics
JF - Biochimica et Biophysica Acta - Bioenergetics
SN - 0005-2728
IS - 7
ER -