WHAT IS THE ROLE OF HOMOLOGOUS cDNA HINT1 IN SUGARCANE?
Saccharum spp., protein model, two-hybrids, interactome, overexpression transgenic lines
The flowering process is a critical step that promotes the transition from the apical meristem from vegetative to the reproductive stage and, consequently, the development of flower structures and seeds. This transition is orchestrated by different external and internal signals that have been characterized in different plant models such as Arabidopsis thaliana, rice and maize. For sugarcane plants not much is known about this process, but it is known that the transition from the apical meristem to the reproductive stage has a strong impact on the juice, sugar and alcohol production. Due to this aspect, this work is part of the research project associated with the identification of genes/proteins that may be associated with this transition from the apical meristem using different bioinformatics and functional genomics tools. The HINT protein was previously identified in subtractive libraries build with induced or non-induced apical meristem. In this work our aim was to understand the role of this protein in sugarcane and plants. We verified that these sequences are conserved in monocots and dicots and these sequences were separate into two large branches. The data obtained from the modeling showed that ScHINT must be functional considering the protein structure as well as the important binding sites for its activity. A second protein was characterized in this work was ScSUBTILASE. This protein was identified in a protein-protein assay using the two-hybrid methods. The ScSUBTILASE protein is also conserved in plants, and modeling has shown that it should also be functional due to the structure obtained and the catalytic sites identified. The results obtained with the interactome for the two proteins using the Arabidopsis model showed that these two sequences are associated with the ROS response. Based on these results presented here and the literature data we may propose that ScHINT and ScSUBTILASE may have the role of keeping the level of ROS adequate to maintain the vegetative apical meristem stage, so when we have the transgenic plants with the antisense cassette (probably with the concentration of these sequences reduced) we obtained a greater production of flowers in Nicotiana tabacum transgenic lines.