Overexpression of the <i>SlPti4</i> Transcription Factor in Transgenic Tobacco Plants Confers Tolerance to Saline, Osmotic, and Drought Stress

The APETALA2/Ethylene Response Factor (AP2/ERF) family of transcription factors (TF) is characterized by their participation in various biological processes related to growth, development, and response to stress. ERFs are ideal candidates for crop improvement because they regulate defense genes like <i>JERF1</i>, <i>JERF3</i>, <i>LeERF2</i>, <i>NtERF5</i>, and <i>Tsil</i> which confer tolerance to drought, salinity, osmotic stress, and pathogen attack, respectively. The ERF subfamily includes the TF Pti4, whose activity is regulated by different signaling pathways, thus providing tolerance response to multiple factors such as drought, salinity, cold, and pathogen attack in tomato. In this work we evaluated the effect of overexpression of TF <i>SlPti4</i> from <i>Solanum lycopersicum</i> in transgenic tobacco plants when subjected to saline, osmotic, and drought stress. Our results from this study demonstrated that transgenic lines overexpressing <i>Pti4</i> tolerate abiotic stress during germination and in plants. The transgenic lines showed improvements in photoinhibition, electron transport rate, chlorophyll content, and biomass, as well as a reduction in malondialdehyde content.