Production of spider silk proteins in tobacco and potato

• Published in: Nature biotechnology 2001-06, Vol.19 (6), p.573-577
• Main Authors: Conrad, Udo, Scheller, Jürgen, Gührs, Karl-Heinz, Grosse, Frank
• Format: Article
• Language: English
• Subjects: Agriculture; Amino Acid Sequence; Animals; Araneae; Araneidae; Bioinformatics; Biological and medical sciences; Biomedical and Life Sciences; Biomedical Engineering/Biotechnology; Biomedicine; Biotechnology; Biotechnology - methods; Cloning; Drug Resistance, Microbial - genetics; Extreme heat; Fundamental and applied biological sciences. Psychology; Genes; Genetic engineering; Genetic technics; Insect Proteins - biosynthesis; Kanamycin - pharmacology; Leaves; Life Sciences; Methods. Procedures. Technologies; Microorganisms; Molecular Sequence Data; Nephila clavipes; Nicotiana; Nicotiana - metabolism; Nicotiana tabacum; Plant tissues; Plants, Genetically Modified - genetics; Plants, Toxic; Potatoes; Proteins; Publishing; Recombinant Proteins - biosynthesis; Sequence Homology, Amino Acid; Silk; Solanum tuberosum; Solanum tuberosum - metabolism; Spiders; Tobacco; Transgenic animals and transgenic plants; Transgenic plants; Vegetables
• ISSN: 1087-0156; 1546-1696
• DOI: 10.1038/89335

Spider dragline silk is a proteinaceous fiber with remarkable mechanical properties that make it attractive for technical applications. Unfortunately, the material cannot be obtained in large quantities from spiders. We have therefore generated transgenic tobacco and potato plants that express remarkable amounts of recombinant Nephila clavipes dragline proteins. Using a gene synthesis approach, the recombinant proteins exhibit homologies of >90% compared to their native models. Here, we demonstrate the accumulation of recombinant silk proteins, which are encoded by synthetic genes of 420–3,600 base pairs, up to a level of at least 2% of total soluble protein in the endoplasmic reticulum (ER) of tobacco and potato leaves and potato tubers, respectively. Using the present expression system, spider silk proteins up to 100 kDa could be detected in plant tissues. When produced in plants, the recombinant spidroins exhibit extreme heat stability—a property that is used to purify the spidroins by a simple and efficient procedure.