Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Adjuvantes Imunológicos/metabolismo , Amilose/biossíntese , Solanum tuberosum/metabolismo , Amido/biossíntese , Enzima Ramificadora de 1,4-alfa-Glucana/genética , Enzima Ramificadora de 1,4-alfa-Glucana/imunologia , Adjuvantes Imunológicos/genética , Amilose/análise , Animais , Anticorpos/genética , Anticorpos/imunologia , Anticorpos/metabolismo , Camelídeos Americanos/imunologia , Camelídeos Americanos/metabolismo , Inibidores Enzimáticos/imunologia , Inibidores Enzimáticos/metabolismo , Regulação Enzimológica da Expressão Gênica/imunologia , Regulação da Expressão Gênica de Plantas/imunologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Solanum tuberosum/enzimologia , Solanum tuberosum/genética , Solanum tuberosum/imunologia , Amido/química , Amido/imunologiaRESUMO
Immunomodulation involves the use of antibodies to alter the function of molecules and is an emerging tool for manipulating both plant and animal systems. To realize the full potential of this technology, two major obstacles must be overcome. First, most antibodies do not function well intracellularly because critical disulfide bonds cannot form in the reducing environment of the cytoplasm or because of difficulties in targeting to subcellular organelles. Second, few antibodies bind to the active sites of enzymes and thus they generally do not neutralize enzyme function. Here we show that the unique properties of single-domain antibodies from camelids (camels and llamas) can circumvent both these obstacles. We demonstrate that these antibodies can be correctly targeted to subcellular organelles and inhibit enzyme function in plants more efficiently than antisense approaches. The use of these single-domain antibody fragments may greatly facilitate the successful immunomodulation of metabolic pathways in many organisms.
Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Adjuvantes Imunológicos/metabolismo , Cadeias Pesadas de Imunoglobulinas/imunologia , Solanum tuberosum/metabolismo , Amido/biossíntese , Enzima Ramificadora de 1,4-alfa-Glucana/genética , Enzima Ramificadora de 1,4-alfa-Glucana/imunologia , Adjuvantes Imunológicos/genética , Amilose/análise , Amilose/biossíntese , Animais , Camelídeos Americanos/imunologia , Camelídeos Americanos/metabolismo , Inibidores Enzimáticos/imunologia , Inibidores Enzimáticos/metabolismo , Regulação Enzimológica da Expressão Gênica/imunologia , Regulação da Expressão Gênica de Plantas/imunologia , Fragmentos de Imunoglobulinas/genética , Fragmentos de Imunoglobulinas/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Tubérculos/enzimologia , Tubérculos/genética , Tubérculos/imunologia , Tubérculos/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/metabolismo , Solanum tuberosum/enzimologia , Solanum tuberosum/genética , Solanum tuberosum/imunologia , Amido/química , Amido/imunologiaRESUMO
Escherichia coli B glycogen synthase and branching enzyme, although similar in amino acid composition, had no significant immunological cross-reactivity. The N-terminal sequences of the glycogen synthase were rich in hydrophobic residues, whereas branching enzyme had a higher content of acidic and basic residues. However, residues 21 to 28 of glycogen synthase and 7 to 14 of branching enzyme shared six of eight residues in common. Two fractions of branching enzyme, branching enzymes I and II, which can be isolated from E. coli B cell extracts, have been shown to be immunologically identical, suggesting that only one type of branching enzyme activity is present in E. coli B. Evidence has been obtained which indicates that E. coli B glycogen synthase and branching enzyme are antigenically very similar to glycogen synthases and branching enzymes from other enteric bacteria. No cross-reactivity with either enzyme was observed in cell extracts from photosynthetic bacteria.
