In 2017, scientists from PEB and CSIRO focused on the roles of the HKT1 gene family in grapevine that encodes for sodium-selective proteins. Initial research focused on the HKT1;1 allelic variant of the HKT1 gene family, to find if it could potentially have an integral role in sodium exclusion due to correlations found between the inheritance of HKT1;1 alleles and leaf sodium content. This has lead to further research into the roles of the other allelic variants within the HKT1 gene cluster, and whether they may have a role in sodium exclusion.
This new research conducted by researchers at PEB focused on the role of the allelic variants HKT1;6, HKT1;7, and HKT1;8 in Cabernet Sauvignon. Looking at these allelic variants, it was found that although HKT1;6 and HKT1;7 were lowly expressed, they may have minor roles in grapevine sodium homeostasis, while HKT1;8 may be involved in regulating sodium concentration within intracellular organelles.
Further questions raised from this research could include whether the low expression could be unregulated by the stimuli tested; therefore low expression may only occur under normal conditions. This research also further concluded the importance of the HKT1;1 allele in sodium exclusion and indicated that a non-HKT candidate located within the HKT1 cluster could be worth investigating regarding its role in sodium tolerance.
This research could be of benefit for the many grape-growers facing undesirable environmental conditions of high saline soils and ensure that in the future high-quality berries can still be cultivated despite increasing adverse environmental conditions in Australia.
The published paper can be viewed in the Journal of Plant Physiology.