Abstract
An insect–plant interaction induced gall formation is where gall wasps change the plant development towards formation of new units to shield and nourish the evolving larvae. The targets of the insect signals and the mechanism of gall development are unknown. To show the molecular pathways that are responsive to the gall wasp, the proteomic approach was used to compare the gall with non-gall plant tissues. We studied three oak gall species (Cynips quercusfolii, Cynips longiventris, and Neuroterus quercusbaccarum) and the host plant (Quercus robur). Among the 21 identified proteins, 18 increased and three decreased in abundance in gall tissue, in comparison to the leaf tissues. Ten proteins were C. quercusfolii responsive, two only with this gall inducer, while seven increased in abundance. Eleven proteins were C. longiventris responsive, and two only with this gall inducer. Sixteen proteins were associated with gall formation by the N. quercusbaccarum and, in this, eight only with this gall inducer. A similar effect on protein abundance occurred as galls in leaf veins (for five proteins). For leaf blades, such a relation was not found. The role of each protein is discussed according to its involvement in the gall formation. Moreover, S-adenosyl methionine synthase, flavone 3-hydroxylase, stress- and pathogenesis-related proteins, and gamma carbonic anhydrase are associated with developmental regulation of plant tissue into a gall.
Highlights
Plant gall induction is common in many insect families, but most of the species belong to only two groups: gall wasps and gall midges (Cook and Gullan 2004)
To identify the molecular mechanism involved in gall formation, we investigated changes in the oak gall proteomes induced by three cynipid wasps commonly found in this region: Cynips quercusfolii, Cynips longiventris, and Neuroterus quercusbaccarum
Sixteen proteins were associated with gall formation by N. quercusbaccarum, in this, eight only with this gall inducer, while 13 increased in abundance
Summary
Plant gall induction is common in many insect families, but most of the species belong to only two groups: gall wasps and gall midges (Cook and Gullan 2004). There are three well-distinguished phases of gall formation: first initiation, subsequent growth, and final maturation (Rohfritsch and Shorthouse 1982; Rey 1992). The host usually reacts with necrosis of cells under the egg; the cells below divide and enclose the egg (Rey 1992; Brooks and Shorthouse 1998; Pilichowski and Giertych 2017). The cell layers of the inner-gall tissue decrease during development because the larvae feed on them. The parenchyma cells are changed into nutritive cells as the larvae feed, and they produce lipids and proteins as well as amylases, which are involved in starch decomposition (Bronner 1992; Rey 1992; Brooks and Shorthouse 1998). Cell division stops, the galls lignify, the larvae mature and
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
