title: Growth modulation effects of CBM2a under the control of AtEXP4 and CaMV35S promoters in Arabidopsis thaliana, Nicotiana tabacum and Eucalyptus camaldulensis.
abstract: The expression of cell-wall-targeted Carbohydrate Binding Modules (CBMs) can alter cell wall properties and modulate growth and development in plants such as tobacco and potato. CBM2a identified in xylanase 10A from Cellulomonas fimi is of particular interest for its ability to bind crystalline cellulose. However, its potential for promoting plant growth has not been explored. In this work, we tested the ability of CBM2a to promote growth when expressed using both CaMV35S and a vascular tissue-specific promoter derived from Arabidopsis expansin4 (AtEXP4) in three plant species: Arabidopsis, Nicotiana tabacum and Eucalyptus camaldulensis. In Arabidopsis, the expression of AtEXP4pro:CBM2a showed trends for growth promoting effects including the increase of root and hypocotyl lengths and the enlargements of the vascular xylem area, fiber cells and vessel cells. However, in N. tabacum, the expression of CBM2a under the control of either CaMV35S or AtEXP4 promoter resulted in subtle changes in the plant growth, and the thickness of secondary xylem and vessel and fiber cell sizes were generally reduced in the transgenic lines with AtEXP4pro:CBM2a. In Eucalyptus, while transgenics expressing CaMV35S:CBM2a showed very subtle changes compared to wild type, those transgenics with AtEXP4pro:CBM2a showed increases in plant height, enlargement of xylem areas and xylem fiber and vessel cells. These data provide comparative effects of expressing CBM2a protein in different plant species, and this finding can be applied for plant biomass improvement.
authors.affiliation: Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand.
authors.forename: Pornthep
authors.initials: P
authors.lastname: Keadtidumrongkul
authors.affiliation: Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand.|Special Research Unit in Microalgal Molecular Genetics and Functional Genomics (MMGFG), Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand.|Center of Advanced Studies for Tropical Natural Resources, Kasetsart University, 50 Ngam Wong Wan, Chatuchak, Bangkok, 10900, Thailand.
authors.forename: Anongpat
authors.initials: A
authors.lastname: Suttangkakul
authors.affiliation: Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand.
authors.forename: Phitsanu
authors.initials: P
authors.lastname: Pinmanee
authors.affiliation: Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand.
authors.forename: Kanokwan
authors.initials: K
authors.lastname: Pattana
authors.affiliation: Department of Biology, Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Chalongkrung Road, Ladkrabang, Bangkok, 10520, Thailand.
authors.forename: Chokchai
authors.initials: C
authors.lastname: Kittiwongwattana
authors.affiliation: Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand.|Special Research Unit in Microalgal Molecular Genetics and Functional Genomics (MMGFG), Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand.|Center of Advanced Studies for Tropical Natural Resources, Kasetsart University, 50 Ngam Wong Wan, Chatuchak, Bangkok, 10900, Thailand.|School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand.
authors.forename: Somsak
authors.initials: S
authors.lastname: Apisitwanich
authors.affiliation: Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand. fsciscv@ku.ac.th.|Special Research Unit in Microalgal Molecular Genetics and Functional Genomics (MMGFG), Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Chatuchak, Bangkok, 10900, Thailand. fsciscv@ku.ac.th.|Center of Advanced Studies for Tropical Natural Resources, Kasetsart University, 50 Ngam Wong Wan, Chatuchak, Bangkok, 10900, Thailand. fsciscv@ku.ac.th.
authors.forename: Supachai
authors.initials: S
authors.lastname: Vuttipongchaikij
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development; D002241:Carbohydrates / Q000235:genetics*; D002473:Cell Wall / Q000235:genetics; D002482:Cellulose / Q000235:genetics; D043364:Endo-1,4-beta Xylanases / Q000235:genetics*; D005052:Eucalyptus / Q000235:genetics / Q000254:growth & development; D018506:Gene Expression Regulation, Plant; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000254:growth & development; D011401:Promoter Regions, Genetic; D014026:Nicotiana / Q000235:genetics / Q000254:growth & development; D052584:Xylem / Q000235:genetics* / Q000254:growth & development
chemical_list: D002241:Carbohydrates; D010940:Plant Proteins; C095825:expansin protein, plant; D002482:Cellulose; D043364:Endo-1,4-beta Xylanases
keywords: Arabidopsis; Carbohydrate binding module; Eucalyptus; Nicotiana tabacum; Plant cell walls; Promoter