The olfactory conditioning of the bee proboscis extension reflex (PER) is extensively used as a paradigm in associative learning of invertebrates but with limited molecular investigations. To investigate which protein changes are linked to olfactory conditioning, a non‐sophisticated conditioning model is applied using the PER in the honeybee (Apis mellifera). Foraging honeybees are assigned into three groups based on the reflex behavior and training: conditioned using 2‐octanone (PER‐conditioned), and sucrose and water controls. Thereafter, the brain synaptosomal proteins are isolated and analyzed by quantitative proteomics using stable isotope labeling (TMT). Additionally, the complex proteome dataset of the bee brain is generated with a total number of 5411 protein groups, including key players in neurotransmitter signaling. The most significant categories affected during olfactory conditioning are associated with “SNARE interactions in vesicular transport” (BET1 and VAMP7), ABC transporters, and fatty acid degradation pathways.

Venoms represent a huge and essentially unexplored reservoir of bioactive components that may cure diseases that do not respond to currently available therapies. This review select advances reported in the literature from 2000 to the present about the new scenario of Hymenoptera venom composition. On account of new technologies in the proteomic approach, which presents high resolution and sensitivity, the combination of developments in new instruments, fragmentation methods, strategic analysis, and mass spectrometry have become indispensable tools for interrogation of protein expression, molecule interaction, and post-translational modifications. Thus, the biochemical characterization of Hymenoptera venom has become a major subject of research in the area of allergy and immunology, in which proteomics has been an excellent alternative to assist the development of more specific extracts for diagnosis and treatment of hypersensitive patients to Hymenoptera venoms.

In order to evaluate the use of matrix-assisted laser desorption ionization (MALDI) Mass Spectral Imaging (MSI) to Glioblastoma (GBM) studies, some sections of formalin fixed paraffin embedded samples of GBM tumors were submitted to classical immunoassays, to define the profile of distribution of some classical and well recognized molecular markers of GBM grade IV (Ki-67, S100, Glial GFAP, CD31 and CD34), while other sections of the same samples were submitted to in-tissue proteomic analysis by MALDI MSI, and both results compared to each other. The overlapping of the MALDI spectra obtained for the tryptic peptides with the immunohistochemical reactions of each marker protein were used to build a distribution map of the marker proteins all over the GBM tissue section. The results revealed a high correlation between both methods, indicating that MALDI MSI has enough sensitivity to be compared to the immunohistochemical methods, as well is sufficiently reliable to be used in biomarkers identification.