title: Isolation, characterization, and functional analysis of a novel cDNA clone encoding a small rubber particle protein from Hevea brasiliensis.
abstract: Biochemical evidence reported so far suggests that rubber synthesis takes place on the surface of rubber particles suspended in the latex of Hevea brasiliensis. We have isolated and characterized a cDNA clone that encodes a protein tightly bound on a small rubber particle. We named this protein small rubber particle protein (SRPP). Prior to this study, this protein was known as a latex allergen, and only its partial amino acid sequence was reported. Sequence analysis revealed that this protein is highly homologous to the rubber elongation factor and the Phaseolus vulgaris stress-related protein. Southern and Northern analyses indicate that the protein is encoded by a single gene and highly expressed in latex. An allergenicity test using the recombinant protein confirmed that the cloned cDNA encodes the known 24-kDa latex allergen. Neither ethylene stimulation nor wounding changed the transcript level of the SRPP gene in H. brasiliensis. An in vitro rubber assay showed that the protein plays a positive role in rubber biosynthesis. Therefore, it is likely that SRPP is a part of the rubber biosynthesis machinery, if not the rubber polymerase, along with the rubber elongation factor.
authors.affiliation: Kumho Life and Environmental Science Laboratory, 1 Oryong-Dong, Puk-Gu, Kwangju 500-480, Korea.
authors.forename: S K
authors.initials: SK
authors.lastname: Oh
authors.forename: H
authors.initials: H
authors.lastname: Kang
authors.forename: D H
authors.initials: DH
authors.lastname: Shin
authors.forename: J
authors.initials: J
authors.lastname: Yang
authors.forename: K S
authors.initials: KS
authors.lastname: Chow
authors.forename: H Y
authors.initials: HY
authors.lastname: Yeang
authors.forename: B
authors.initials: B
authors.lastname: Wagner
authors.forename: H
authors.initials: H
authors.lastname: Breiteneder
authors.forename: K H
authors.initials: KH
authors.lastname: Han
mesh_terms: D000485:Allergens; D000595:Amino Acid Sequence; D052179:Antigens, Plant; D001483:Base Sequence; D019665:Euphorbiaceae / Q000235:genetics*; D018628:Gene Dosage; D015870:Gene Expression; D017343:Genes, Plant; D020315:Latex Hypersensitivity; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D012408:Rubber / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013729:Terpenes / Q000378:metabolism; D014197:Trees / Q000235:genetics*
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D010940:Plant Proteins; C119716:SRPP protein, Hevea brasiliensis; D013729:Terpenes; D012408:Rubber