Back to Search
Start Over
A Lettuce (Lactuca sativa) Homolog of Human Nogo-B Receptor Interacts with cis-Prenyltransferase and Is Necessary for Natural Rubber Biosynthesis*
- Publication Year :
- 2014
- Publisher :
- American Society for Biochemistry and Molecular Biology, 2014.
-
Abstract
- Natural rubber (cis-1,4-polyisoprene) is an indispensable biopolymer used to manufacture diverse consumer products. Although a major source of natural rubber is the rubber tree (Hevea brasiliensis), lettuce (Lactuca sativa) is also known to synthesize natural rubber. Here, we report that an unusual cis-prenyltransferase-like 2 (CPTL2) that lacks the conserved motifs of conventional cis-prenyltransferase is required for natural rubber biosynthesis in lettuce. CPTL2, identified from the lettuce rubber particle proteome, displays homology to a human NogoB receptor and is predominantly expressed in latex. Multiple transgenic lettuces expressing CPTL2-RNAi constructs showed that a decrease of CPTL2 transcripts (3-15% CPTL2 expression relative to controls) coincided with the reduction of natural rubber as low as 5%. We also identified a conventional cis-prenyltransferase 3 (CPT3), exclusively expressed in latex. In subcellular localization studies using fluorescent proteins, cytosolic CPT3 was relocalized to endoplasmic reticulum by co-occurrence of CPTL2 in tobacco and yeast at the log phase. Furthermore, yeast two-hybrid data showed that CPTL2 and CPT3 interact. Yeast microsomes containing CPTL2/CPT3 showed enhanced synthesis of short cis-polyisoprenes, but natural rubber could not be synthesized in vitro. Intriguingly, a homologous pair CPTL1/CPT1, which displays ubiquitous expressions in lettuce, showed a potent dolichol biosynthetic activity in vitro. Taken together, our data suggest that CPTL2 is a scaffolding protein that tethers CPT3 on endoplasmic reticulum and is necessary for natural rubber biosynthesis in planta, but yeast-expressed CPTL2 and CPT3 alone could not synthesize high molecular weight natural rubber in vitro.
- Subjects :
- Proteomics
Latex
Green Fluorescent Proteins
Molecular Sequence Data
Plant Biology
Agrobacterium
Lactuca
Receptors, Cell Surface
Biology
Endoplasmic Reticulum
Biochemistry
complex mixtures
Natural rubber
Transferases
Microsomes
Two-Hybrid System Techniques
Yeasts
Tobacco
Amino Acid Sequence
Molecular Biology
Plant Proteins
Microscopy, Confocal
Sequence Homology, Amino Acid
Endoplasmic reticulum
technology, industry, and agriculture
food and beverages
Cell Biology
DNA
Lettuce
Subcellular localization
biology.organism_classification
Plants, Genetically Modified
Yeast
body regions
Molecular Weight
Phenotype
visual_art
Microsome
visual_art.visual_art_medium
Hevea
RNA Interference
Hevea brasiliensis
Chromatography, Thin Layer
Rubber
psychological phenomena and processes
Protein Binding
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Accession number :
- edsair.doi.dedup.....ed3b642777ed76e45202a7f3b49d1f2e