Profiling the Proteome of Cyst Nematode-Induced Syncytia on Tomato Roots

Abstract

Cyst nematodes are important herbivorous pests in agriculture that obtain nutrients through specialized root structures termed syncytia. Syncytium initiation, development, and functioning are a research focus because syncytia are the primary interface for molecular interactions between the host plant and parasite. The small size and complex development (over approximately two weeks) of syncytia hinder precise analyses, therefore most studies have analyzed the transcriptome of infested whole-root systems or syncytia-containing root segments. Here, we describe an effective procedure to microdissect syncytia induced by Globodera rostochiensis from tomato roots and to analyze the syncytial proteome using mass spectrometry. As little as 15 mm2 of 10-µm-thick sections dissected from 30 syncytia enabled the identification of 100–200 proteins in each sample, indicating that mass-spectrometric methods currently in use achieved acceptable sensitivity for proteome profiling of microscopic samples of plant tissues (approximately 100 µg). Among the identified proteins, 48 were specifically detected in syncytia and 7 in uninfected roots. The occurrence of approximately 50% of these proteins in syncytia was not correlated with transcript abundance estimated by quantitative reverse-transcription PCR analysis. The functional categories of these proteins confirmed that protein turnover, stress responses, and intracellular trafficking are important components of the proteome dynamics of developing syncytia.

Proteomics of Reproductive Development, Fruit Ripening, and Stress Responses in Tomato

“…One such report of the nematode-infected root syncytia of tomato cv. ‘Moneymaker’ was investigated to determine the roles of proteasome α-subunit (PSC5-PAD1), l -ascorbate oxidase homologue pectinesterase (PE-ASCO), tolB-like protein (TOLB), peroxidase (POD), hexokinases (HXK1), GDSL esterase/lipase, plasma membrane ATPase (LHA-LHA2), heat shock cognate 70 kDa protein 2 (HSC2L), calmodulin 1 (CAM1), and chaperonin 6 β-subunit (CPN60B2) . The impact of these abundant proteins reveal the significance of organelle de novo biogenesis and autophagy along with redox homeostasis, portraying the metabolic and proteomic significance of the nematode interaction with plants.…”