Two Distinct Jacalin-Related Lectins with a Different Specificity and Subcellular Location Are Major Vegetative Storage Proteins in the Bark of the Black Mulberry Tree1
AUTOR(ES)
Van Damme, Els J.M.
FONTE
American Society of Plant Physiologists
RESUMO
Using a combination of protein isolation/characterization and molecular cloning, we have demonstrated that the bark of the black mulberry tree (Morus nigra) accumulates large quantities of a galactose-specific (MornigaG) and a mannose (Man)-specific (MornigaM) jacalin-related lectin. MornigaG resembles jacalin with respect to its molecular structure, specificity, and co- and posttranslational processing indicating that it follows the secretory pathway and eventually accumulates in the vacuolar compartment. In contrast, MornigaM represents a novel type of highly active Man-specific jacalin-related lectin that is synthesized without signal peptide or other vacuolar targeting sequences, and accordingly, accumulates in the cytoplasm. The isolation and cloning, and immunocytochemical localization of MornigaG and MornigaM not only demonstrates that jacalin-related lectins act as vegetative storage proteins in bark, but also allows a detailed comparison of a vacuolar galactose-specific and a cytoplasmic Man-specific jacalin-related lectin from a single species. Moreover, the identification of MornigaM provides the first evidence, to our knowledge, that bark cells accumulate large quantities of a cytoplasmic storage protein. In addition, due to its high activity, abundance, and ease of preparation, MornigaM is of great potential value for practical applications as a tool and bioactive protein in biological and biomedical research.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=166604Documentos Relacionados
- Bark and Leaf Lectins of Sophora japonica Are Sequestered in Protein-Storage Vacuoles 1
- Two Closely Related Wheat Storage Proteins Follow a Markedly Different Subcellular Route in Xenopus laevis Oocytes.
- Plasma Membrane Aquaporins Are Involved in Winter Embolism Recovery in Walnut Tree1
- The Two Variants of Oxysterol Binding Protein-related Protein-1 Display Different Tissue Expression Patterns, Have Different Intracellular Localization, and Are Functionally Distinct
- Different TRE-related elements are distinguished by sets of DNA-binding proteins with overlapping sequence specificity.