Results for “feeding-site maintenance”

PubMed2026

From Sequential Gland Replacement to Recurrent Gland Coordination: A Comparative Framework for Subventral and Dorsal Oesophageal Gland Effectors Across Plant-Parasitic Nematode Lifestyles.

Plant-parasitic nematodes manipulate host tissues through stylet-secreted gene products synthesised principally in two subventral and one dorsal oesophageal gland. Earlier reviews have catalogued effector repertoires, described feeding-site formation, and explained how individual effectors modify host defence, development, and metabolism. However, the temporal coordination of the gland cells themselves has not been comparatively synthesised across parasitic lifestyles. This review therefore advances a gland-centred, lifestyle-dependent framework. In sedentary endoparasites, available evidence supports a pronounced developmental transition: subventral gland products dominate penetration and migration, whereas dorsal gland products become increasingly important during feeding-site initiation and maintenance. Migratory endoparasites repeatedly penetrate, migrate, and feed without establishing permanent feeding cells; their gland activity is consequently predicted to be recurrent and overlapping rather than a one-way replacement. Ectoparasites likewise require behaviour-dependent coordination during repeated probing and external feeding, although direct gland localisation evidence remains limited. We integrate gland origin, secretion chemistry, infection stage, and parasitic behaviour across root-knot, cyst, citrus, false root-knot, lesion, burrowing, and ectoparasitic nematodes. The synthesis distinguishes experimentally demonstrated gland localisation from evidence-weighted inference and formulates testable predictions for comparative gland transcriptomics, spatial expression, and functional silencing. This framework also identifies gland activation, secretion, and stage-critical products as targets for RNA interference, genome editing, resistance breeding, and sustainable nematode management. The principal novelty is therefore not another catalogue of nematode effectors, but a comparative model explaining when and why subventral and dorsal glands exchange, retain, or alternate their functions across contrasting parasitic lifestyles.

dorsal gland↗

PubMed2005

Nematode-induced changes of transporter gene expression in Arabidopsis roots.

Root-knot plant-parasitic nematodes (Meloidogyne spp.) account for much of the damage inflicted to plants by nematodes. The feeding sites of these nematodes consist of "giant" cells, which have characteristics of transfer cells found in other parts of plants. Increased transport activity across the plasma membrane is a hallmark of transfer cells, and giant cells provide nutrition for nematodes; therefore, we initiated a study to identify the transport processes that contribute to the development and function of nematode-induced feeding sites. The study was conducted over a 4-week period, during which time the large changes in the development of giant cells were documented. The Arabidopsis ATH1 GeneChip was used to identify the many transporter genes that were regulated by nematode infestation. Expression of 50 transporter genes from 18 different gene families was significantly changed upon nematode infestation. Sixteen transporter genes were studied in more detail using real-time reverse-transcriptase polymerase chain reaction to determine transcript abundance in nematode-induced galls that contain giant cells and uninfested regions of the root. Certain genes were expressed primarily in galls whereas others were expressed primarily in the uninfested regions of the root, and a third group was expressed evenly throughout the root. Multiple transport processes are regulated and these may play important roles in nematode feeding-site establishment and maintenance.

Amino Acids↗