TY - JOUR
T1 - Three different genes encode the iron-sulfur subunit of succinate dehydrogenase in Arabidopsis thaliana
AU - Figueroa, Pablo
AU - León, Gabriel
AU - Elorza, Alvaro
AU - Holuigue, Loreto
AU - Jordana, Xavier
N1 - Funding Information:
We are greatly indebted to Simon Litvak, Alejan-dro Araya and Laura Tarragó-Litvak for their support, especially during the stay of one of us (P.F.) in their laboratory. We also would like to thank Jean-Claude Farré for fruitful discussions. This work was supported by research grants 8980005 (Líneas complementarias), 2000073 and 2970071 (Ph.D. students) from Fondecyt-Chile, and C98B01 from ECOS (France)-Conicyt (Chile).
PY - 2001
Y1 - 2001
N2 - The iron-sulfur protein is an essential component of mitochondrial complex II (succinate dehydrogenase, SDH), which is a functional enzyme of both the citric acid cycle and the respiratory, electron transport chain. This protein is encoded by a single-copy nuclear gene in mammals and fungi and by a mitochondrial gene in Rhodophyta and the protist Reclinomonas americana. In Arabidopsis thaliana, the homologous protein is now found to be encoded by three nuclear genes. Two genes (sdh2-1 and sdh2-2) likely arose from a relatively recent duplication event since they have similar structures, encode nearly identical proteins and show similar expression patterns. Both genes are interrupted by a single intron located at a conserved position. Expression was detected in all tissues analysed, with the highest steady-state mRNA levels found in flowers and inflorescences. In contrast, the third gene (sdh2-3) is interrupted by 4 introns, is expressed at a low level, and encodes a SDH2-3 protein which is only 67% similar to SDH2-1 and SDH2-2 and has a different N-terminal presequence. Interestingly, the proteins encoded by these three genes are probably functional because they are highly conserved compared with their homologues in other organisms. These proteins contain the cysteine motifs involved binding the three iron-sulfur clusters essential for electron transport. Furthermore, the three polypeptides are found to be imported into isolated plant mitochondria.
AB - The iron-sulfur protein is an essential component of mitochondrial complex II (succinate dehydrogenase, SDH), which is a functional enzyme of both the citric acid cycle and the respiratory, electron transport chain. This protein is encoded by a single-copy nuclear gene in mammals and fungi and by a mitochondrial gene in Rhodophyta and the protist Reclinomonas americana. In Arabidopsis thaliana, the homologous protein is now found to be encoded by three nuclear genes. Two genes (sdh2-1 and sdh2-2) likely arose from a relatively recent duplication event since they have similar structures, encode nearly identical proteins and show similar expression patterns. Both genes are interrupted by a single intron located at a conserved position. Expression was detected in all tissues analysed, with the highest steady-state mRNA levels found in flowers and inflorescences. In contrast, the third gene (sdh2-3) is interrupted by 4 introns, is expressed at a low level, and encodes a SDH2-3 protein which is only 67% similar to SDH2-1 and SDH2-2 and has a different N-terminal presequence. Interestingly, the proteins encoded by these three genes are probably functional because they are highly conserved compared with their homologues in other organisms. These proteins contain the cysteine motifs involved binding the three iron-sulfur clusters essential for electron transport. Furthermore, the three polypeptides are found to be imported into isolated plant mitochondria.
KW - Arabidopsis thaliana
KW - Iron-sulfur subunit
KW - Mitochondrial targeting
KW - Plant mitochondria
KW - Respiratory complex II
KW - Succinate dehydrogenase
UR - http://www.scopus.com/inward/record.url?scp=0034952468&partnerID=8YFLogxK
U2 - 10.1023/A:1010612506070
DO - 10.1023/A:1010612506070
M3 - Article
C2 - 11442063
AN - SCOPUS:0034952468
SN - 0167-4412
VL - 46
SP - 241
EP - 250
JO - Plant Molecular Biology
JF - Plant Molecular Biology
IS - 2
ER -