title: Isolation and analysis of α-expansin genes in the tree Anthocephalus chinensis (Rubiaceae).
abstract: Expansins are cell wall-associated proteins that induce wall extension and relax stress by disrupting noncovalent bonds between cellulose microfibrils and cross-linking glycan chains, thereby promoting wall creep. Anthocephalus chinensis is a very fast-growing economically important tree found mainly in South Asia. Sixteen cDNAs, designated AcEXPA1 to AcEXPA16 (GenBank accession Nos. FJ417847, JF922686-JF922700) with corresponding genomic DNA sequences (GenBank accession Nos. GQ228823, JF922701-JF922715), were isolated by amplifying conserved domain binding with genomic walking and RACE techniques from four differential growth tissues in A. chinensis. These α-expansin homologues were highly conserved in size and sequence; they had the same sequence structures as an N-terminal signal peptide, three exons and two introns. Their amino acid alignment showed that A. chinensis expansin genes are divided into three subgroups: A, B and C. This study is the first report on expansin genes from A. chinensis. It will be used for a tissue-specific expression model and for studying the relationship between expansin genes, growth rate and wood quality of the xylem in this fast-growing tree.
authors: Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants, Ministry of Education, National Engineering Laboratory for Forest Tree Breeding, Beijing Forestry University, Beijing, China.
authors: K X
authors: KX
authors: Ouyang
authors: M Q
authors: MQ
authors: Liu
authors: R Q
authors: RQ
authors: Pian
authors: S S
authors: SS
authors: Liu
authors: X Y
authors: XY
authors: Chen
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D023061:Gene Order; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D011257:Pregnancy Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D019666:Rubiaceae / Q000235:genetics*; D016415:Sequence Alignment; D014197:Trees / Q000235:genetics*
chemical_list: D018076:DNA, Complementary; D011257:Pregnancy Proteins