Seed-produced anti-globulin VHH-Fc antibodies retrieve globulin precursors in the insoluble fraction and modulate the Arabidopsis thaliana seed subcellular morphology.
Plant Mol Biol
; 103(6): 597-608, 2020 Aug.
Article
em En
| MEDLINE
| ID: mdl-32346812
ABSTRACT
KEY MESSAGE Nanobody-heavy chain (VHH-Fc) antibody formats have the potential to immunomodulate even highly accumulating proteins and provide a valuable tool to experimentally modulate the subcellular distribution of seed storage proteins. Recombinant antibodies often obtain high accumulation levels in plants, and thus, besides being the actual end-product, antibodies targeting endogenous host proteins can be used to interfere with the localization and functioning of their corresponding antigens. Here, we compared the effect of a seed-expressed nanobody-heavy chain (VHH-Fc) antibody against the highly abundant Arabidopsis thaliana globulin seed storage protein cruciferin with that of a VHH-Fc antibody without endogenous target. Both antibodies reached high accumulation levels of around 10% of total soluble protein, but strikingly, another significant part was present in the insoluble protein fraction and was recovered only after extraction under denaturing conditions. In seeds containing the anti-cruciferin antibodies but not the antibody without endogenous target, the amount of soluble, processed globulin subunits was severely reduced and a major part of the cruciferin molecules was found as precursor in the insoluble fraction. Moreover, in these seeds, aberrant vacuolar phenotypes were observed that were different from the effects caused by the depletion of globulins in knock-out seeds. Remarkably, the seeds with strongly reduced globulin amounts are fully viable and germinate with frequencies similar to wild type, illustrating how flexible seeds can retrieve amino acids from the stored proteins to start germination.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Armazenamento de Sementes
/
Globulinas
/
Anticorpos
Idioma:
En
Revista:
Plant Mol Biol
Assunto da revista:
BIOLOGIA MOLECULAR
/
BOTANICA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Bélgica