title: Identification and subcellular localization analysis of two rubber elongation factor isoforms on Hevea brasiliensis rubber particles.
abstract: Rubber elongation factor (REF) is the most abundant protein found on the rubber particles or latex from Hevea brasiliensis (the Para rubber tree) and is considered to play important roles in natural rubber (cis-polyisoprene) biosynthesis. 16 BAC (benzyldimethyl-n-hexadecylammonium chloride)/SDS-PAGE separations and mass spectrometric identification had revealed that two REF isoforms shared similar amino acid sequences and common C-terminal sequences. In this study, the gene sequences encoding these two REF isoforms (one is 23.6 kDa in size with 222 amino acid residues and the other is 27.3 kDa in size with 258 amino acid residues) were obtained. Their proteins were relatively enriched by sequential extraction of the rubber particle proteins and separated by 16 BAC/SDS-PAGE. The localization of these isoforms on the surfaces of rubber particles was further verified by western blotting and immunogold electron microscopy, which demonstrated that these two REF isoforms are mainly located on the surfaces of larger rubber particles and that they bind more tightly to rubber particles than the most abundant REF and SRPP (small rubber particle protein).
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Rubber Tree, Ministry of Agriculture, PR China; State Key Laboratory Incubation Base, Danzhou, Hainan, PR China; Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, PR China. Electronic address: dailongjun@126.com.
authors.forename: Longjun
authors.initials: L
authors.lastname: Dai
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Rubber Tree, Ministry of Agriculture, PR China; State Key Laboratory Incubation Base, Danzhou, Hainan, PR China; Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, PR China. Electronic address: narzizip@163.com.
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Nie
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Rubber Tree, Ministry of Agriculture, PR China; State Key Laboratory Incubation Base, Danzhou, Hainan, PR China; Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, PR China. Electronic address: kangguijuan2010@126.com.
authors.forename: Guijuan
authors.initials: G
authors.lastname: Kang
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Rubber Tree, Ministry of Agriculture, PR China; State Key Laboratory Incubation Base, Danzhou, Hainan, PR China; Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, PR China. Electronic address: liyu692@gmail.com.
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Biology and Genetic Resources of Rubber Tree, Ministry of Agriculture, PR China; State Key Laboratory Incubation Base, Danzhou, Hainan, PR China; Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, PR China. Electronic address: hnzrz@aliyun.com.
authors.forename: Rizhong
authors.initials: R
authors.lastname: Zeng
mesh_terms: D000595:Amino Acid Sequence; D052179:Antigens, Plant / Q000378:metabolism*; D015153:Blotting, Western; D002021:Buffers; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D005233:Fatty Alcohols / Q000737:chemistry; D028482:Hevea / Q000378:metabolism*; D007150:Immunohistochemistry; D007840:Latex / Q000737:chemistry; D013058:Mass Spectrometry; D017830:Octoxynol / Q000737:chemistry; D016366:Open Reading Frames / Q000235:genetics; D010455:Peptides / Q000737:chemistry; D010802:Phylogeny; D010940:Plant Proteins / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D020033:Protein Isoforms / Q000378:metabolism; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012408:Rubber / Q000378:metabolism*; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D052179:Antigens, Plant; D002021:Buffers; D005233:Fatty Alcohols; D007840:Latex; D010455:Peptides; D010940:Plant Proteins; D020033:Protein Isoforms; D000644:Quaternary Ammonium Compounds; C061477:REF protein, Hevea brasiliensis; C012817:cetalkonium chloride; D017830:Octoxynol; D012408:Rubber
keywords: Hevea brasiliensis; Rubber elongation factor; Rubber particles; Subcellular localization