Molecular cloning, sequence characterization of a  novel pepper gene NADP-ICDH and its effect on cytoplasmic male sterility.
NADP-dependent isocitrate dehydrogenase (NADP-ICDH)  is an important enzyme involved in energy metabolism. The complete coding sequence  of the pepper (Capsicum annuum) NADP-ICDH gene was amplified  using a reverse transcriptase PCR based on the conserved sequence information  of the tomato and other Solanaceae plants and known highly homologous pepper  ESTs. Nucleotide sequence analysis revealed that the pepper NADP-ICDH gene  encodes a protein of 415 amino acids that has high homology with the proteins  of seven species, Solanum tuberosum (100%), Citrus limon (98%), Daucus  carota (98%), Nicotiana tabacum (98%), Vitis vinifera (99%), Arabidopsis  thaliana (97%), and Oryza sativa (98%). Tissue expression analysis  demonstrated that the pepper NADP-ICDH gene is over expressed in flower,  pericarp and seed, moderately in placenta, weakly in stem and leaf, hardly  expressed in root. At the abortion stages, activities and expression levels of NADP-ICDH in anthers of a sterile line were strongly reduced, while those in an F(1) hybrid remained  normal. Activities and expression levels of NADP-ICDH were too low to  maintain balanced energy metabolism in the sterile line, which indicated that  stable transcripts of NADP-ICDH are necessary to maintain energy  metabolism at a normal level. When the restorer gene was transferred to the  cytoplasmic male sterile line, activities and expression level of NADP-ICDH were  regulated by the restorer gene and became stable. The restorer gene likely  plays an important role in keeping the balance of the energy metabolism within  normal levels during microspore development.
Institute of Vegetable Crops, Hunan Academy of Agricultural Science, Changsha, China.
M H
MH
Deng
J F
JF
Wen
J L
JL
Huo
H S
HS
Zhu
X Z
XZ
Dai
Z Q
ZQ
Zhang
H
H
Zhou
X X
XX
Zou
D000595:Amino Acid Sequence; D001483:Base Sequence; D002212:Capsicum / Q000201:enzymology* / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D019143:Evolution, Molecular; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics*; D007521:Isocitrate Dehydrogenase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics; D010802:Phylogeny; D051479:Plant Infertility / Q000235:genetics*; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D040681:Structural Homology, Protein
D018076:DNA, Complementary; D012333:RNA, Messenger; D007521:Isocitrate Dehydrogenase; C039355:isocitrate dehydrogenase (NADP+)