title: Molecular cloning, expression and mapping analysis of a novel cytosolic ascorbate peroxidase gene from tomato.
abstract: Ascorbate peroxidase (APX, EC 1.11.1.11) plays a major role in H(2)O(2)-scavenging in plants and can help to avoid reactive oxygen species (ROS) damage. A new cytosolic APX gene was cloned from tomato (designated LecAPX2) by RACE-PCR. The full-length cDNA of LecAPX2 contained a complete open reading frame (ORF) of 753 bp, which encoding 250 amino acid residues. Homology analysis of LecAPX2 showed a 94% identity with potato cAPX gene and 92% identity with another tomato cAPX gene (APX20), the deduced amino acid showed 88% homology with APX20 protein and 75-92% identity with cAPX from other plants such as potato, tobacco, broccoli, spinach, pea, rice, etc. LecAPX2 revealed the existence of a haem peroxidase and plant APX family signatures. Northern blot analysis showed that LecAPX2 was constitutively expressed in root, stem, leaf, flower and fruit of tomato, whereas the expression levels were different. LecAPX2 was mapped to 6-A using 75 tomato introgression lines (ILs), each containing a single homozygous RFLP-defined chromosome segment from the green-fruited species Lycopersicon pennellii.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Zou
authors.forename: Han-Xia
authors.initials: HX
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Ouyang
authors.forename: Jun-Hong
authors.initials: JH
authors.lastname: Zhang
authors.forename: Zhi-Biao
authors.initials: ZB
authors.lastname: Ye
mesh_terms: D000595:Amino Acid Sequence; D060387:Ascorbate Peroxidases; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D003600:Cytosol / Q000201:enzymology; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D015870:Gene Expression; D017343:Genes, Plant; D018551:Solanum lycopersicum / Q000201:enzymology* / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010544:Peroxidases / Q000235:genetics*; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
chemical_list: D018076:DNA, Complementary; D018744:DNA, Plant; D012333:RNA, Messenger; D018749:RNA, Plant; D010544:Peroxidases; D060387:Ascorbate Peroxidases