title: Molecular characterization of plantain class i chitinase gene and its expression in response to infection by Gloeosporium musarum Cke and Massee and other abiotic stimuli.
abstract: We have cloned a chitinase cDNA (MpChi-1) from plantain (Musa paradisiacal L) using rapid amplification of cDNA ends (RACE) according to a sequence fragment which we had cloned using the suppression subtractive hybridization (SSH) technique. The MpChi-1 encodes a protein of 326 amino acids and belongs to acidic chitinase class Ib subfamily. MpChi-1 shares high identity with rice endochitinase (XP_468714) and different each other only at three residues. Homology modelling indicated these three substitutions would not change the configuration of the activity site of the enzyme. We have expressed recombinant MpChi-1 and purified by ammonium sulphate precipitation and preparative reversed phase HPLC. The recombinant protein could hydrolyse chitin and inhibit the growth of the Gloeosporium musarum Cke and Massee in vitro. Northern blot revealed that the MpChi-1 transcripts rapidly after inoculation with G. musarum and maximum mRNA accumulation reached at 48 h. Jasmonic acid (JA) and salicylic acid (SA) could induce MpChi-1 expression, while mechanical wounding, silver nitrate and osmotic stress stimulated only a slight accumulation of MpChi-1 transcripts. Abscisic acid (ABA) could induce MpChi-1 transcript. These results suggest the MpChi-1 plays important role in the events of the hypersensitive reaction (HR).
authors.affiliation: The State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Jianming
authors.initials: J
authors.lastname: Fan
authors.forename: Hongbin
authors.initials: H
authors.lastname: Wang
authors.forename: Dongru
authors.initials: D
authors.lastname: Feng
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.forename: Haiyan
authors.initials: H
authors.lastname: Liu
authors.forename: Jinfa
authors.initials: J
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000502:physiology*; D001483:Base Sequence; D002688:Chitinases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D003517:Cyclopentanes / Q000494:pharmacology; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D006967:Hypersensitivity; D007239:Infections / Q000378:metabolism* / Q000473:pathology; D008969:Molecular Sequence Data; D028521:Musa; D009997:Osmotic Pressure; D054883:Oxylipins / Q000494:pharmacology; D010943:Plantago; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020156:Salicylic Acid / Q000494:pharmacology; D012835:Silver Nitrate / Q000494:pharmacology; D013314:Stress, Mechanical; D013997:Time Factors
chemical_list: D003517:Cyclopentanes; D018076:DNA, Complementary; D054883:Oxylipins; D012333:RNA, Messenger; D011994:Recombinant Proteins; C011006:jasmonic acid; D012835:Silver Nitrate; D002688:Chitinases; D020156:Salicylic Acid