Interactomic analysis of the sHSP family during tomato fruit ripening

Small Heat Shock Proteins (sHSPs) are chaperones related to abiotic stress response and development that have been characterized in different organisms. In plants, evolutionary relationships, differential gene expression and HSE-dependent gene regulation of tomato sHSP family was described by different groups in an exploratory approach. This work enhances a bioinformatic and inferential approach based on PPI network building using previously reported transcriptomic and proteomic curated datasets. We were able to identify the already described core set of eight sHSPs showing different subcellular localization. Additionally, new putative sHSP-protein interactors during fruit ripening were defined. Between them, HSP70 members, chaperones (DnaK, DnaJ), GST and Universal Stress Protein are the main proteins associated to biological processes involved in response to heat, abiotic stress, protein folding and development. Finally, protein expression of these interactors depends on the presence of HSE and CTAGA-motifs in their gene promoter regions, suggesting Hsf-dependent regulation. Our inferential and integrative bioinformatic approach led us to identify new possible biological roles for subsets of genes/proteins in a system biology point of view, during tomato fruit ripening.