Fuente: PubMed "industrial biotechnology" Plant Cell Physiol. 2026 Apr 20:pcag050. doi: 10.1093/pcp/pcag050. Online ahead of print.ABSTRACTThe leaves of the carnivorous plant Byblis guehoi (B. guehoi) are densely covered with structurally simple sessile trichomes, each composed of eight flattened cells arranged in a ring. These trichomes exhibit robust protein exocytosis and endocytosis, making them a suitable system for studying these processes. To track protein secretion, we established an Agrobacterium-mediated transformation protocol using root explants. Calli were induced on Byblis Callus Induction Medium (BCIM), and transgenic shoots were regenerated within two months on hygromycin-containing Byblis Selection and Regeneration Medium (BSRM). In addition, a temporary immersion system (TIS) was implemented to rapidly propagate transgenic lines, enhancing growth and facilitating acclimation. Four 35S promoter-driven constructs expressing GUS, RUBY, mGFP5, or CLV3sp-mGFP5 validated the protocol, yielding transformation efficiencies of 24.9-59.4% and regeneration efficiencies of 22.3-73.7%. Confocal microscopy revealed predominantly cytoplasmic signals for mGFP5 and plasma membrane-localized signals for CLV3sp-mGFP5 in epidermal cells. Unexpectedly, both constructs exhibited GFP signals at the plasma membrane and in the extracellular space of sessile trichome cells, regardless of the presence of a signal peptide. Western blot analysis further confirmed that mGFP5 was secreted into the mucilage independently of signal peptide presence. These findings reveal signal peptide-independent extracellular protein accumulation in glandular trichomes, deviating from the classical ER-Golgi pathway. Given that sessile trichomes of B. guehoi possess a specialized cuticular pore lacking a rigid cell wall, this structural feature may provide a plausible interface for non-classical protein export. This study establishes a rapid transformation-propagation pipeline for B. guehoi, highlighting its potential as an experimental platform for investigating protein secretion in plant glandular cells.PMID:42007579 | DOI:10.1093/pcp/pcag050