Eucalyptus are widely cultivated in several regions of the world due to their adaptability to different climatic conditions and amenable to tree breeding programs. With changes in environmental conditions pointing to an increase in aridity in many areas of the globe, the demand for genetic materials that adapt to this situation is required. Therefore, the aim of this work was to identify contrasting differences between two Eucalyptus species under
water stress through the identification of differentially abundant
proteins. For this, total
protein extraction was proceeded from leaves of both species maintained at 40 and 80% of field capacity (FC). The 80% FC water regime was considered as the control and the 40% FC, severe
water stress. The
proteins were separated by 2-DE with subsequent identification of those differentially abundant by liquid nanocromatography coupled to high resolution MS (Q-Exactive). Comparative proteomics allowed to identify four
proteins (
ATP synthase gamma and alpha,
glutamine synthetase and a vacuolar
protein) that were more abundant in drought-tolerant species and simultaneously less abundant or unchanged in the drought- sensitive species, an uncharacterized
protein found exclusively in plants under drought stress and also 10
proteins (plastid-
lipid,
ruBisCO activase,
ruBisCO,
protease ClpA,
transketolase,
isoflavone reductase,
ferredoxin-NADP reductase,
malate dehydrogenase, aminobutyrate
transaminase and
sedoheptulose-1-bisphosphatase) induced exclusively in the drought-tolerant species in response to
water stress. These results suggest that such
proteins may play a crucial role as potential markers of
water stress tolerance through the identification of species-specific
proteins, and future targets for genetic engineering.