Exploring the role of HaTIPs genes in enhancing drought tolerance in sunflower.

Background: Activity of plant aquaporins (AQPs) is extremely sensitive to environmental variables such as temperature, drought, atmospheric vapor pressure deficit, cell water status and also appears to be closely associated with the expression of plant tolerance to various stresses. The spatial and temporal expression patterns of genes of Tonoplast Intrinsic Proteins (TIPs) in various crops indicate the complex and diverse regulation of these proteins and are important in understanding their key role in plant growth, development and stress responses. Methods and results: Based on phylogenetic analysis, six distinct HaTIPs were selected for studying their spatial and temporal expression in sunflower (Helianthus annuus). In this study semi quantitative polymerase chain reaction (semi q-PCR) and real time polymerase chain reaction (q-PCR) analysis were used to study the spatial and temporal expression of HaTIPs in sunflower. The results indicated that all of HaTIPs showed differential expression specific to both the tissues and the accessions. Moreover, the expression of all HaTIPs was higher in cross compared to the parents. Results of semi q-PCR and real time PCR indicated an upregulation of expression of HaTIP-RB7 and HaTIP7 in drought tolerant entries at 12 h of 20% polyethylene glycol (PEG) treatment compared to 0 h. Conclusion: Hence these genes can be utilized as potential target in improving water use efficiency and for further genetic manipulation for the development of drought tolerant sunflower. This study may further contribute to our better understanding regarding the precise role of HaTIPs through their spatial and temporal expression analysis and their application in sunflower drought stress responses. [ABSTRACT FROM AUTHOR]