Once the protein was produced, the team began a series of analyses to elucidate some of the features of the newly cloned Solanum dulcamara THP. They did a western blot, a gel shift assay, RNA blot analysis, and analysed the hysteresis activity. Following the completion of these analyses, they identified STHP-64 as the hydrophilic THP protein present in the November sample of Solanum dulcamara. It differed in weight slightly (3 kDa) compared to the original THP used as a template, but they attributed this to the loss of exons from the N-terminus. Functionally and structurally, the protein was extremely similar to the original and they believed that it was derived from the same gene within the plant. They observed thermal hysteresis activity for STHP-64, albeit not much. Citrate was found to increase the thermal hysteresis activity, which confirmed for them that STHP was in fact THP. The low activity was attributed to potential protein-folding issues among other things. Amino acid repeats were identified in the clone and thought to facilitate thermal hysteresis by hydrogen bonding with the ice on the plant, effectively inhibiting the further crystallization of ice. STHP-64 also demonstrated DNA-binding ability and they believed that it could act as a transcription factor for the upregulation of proteins related to pathogenesis. In conclusion, although the THP activity was low in the isolated sample from Solanum dulcamara, the THP protein was only present in the November sample. This suggests that STHP-64 is at least partially responsible for the overwintering capabilities demonstrated by Solanum dulcamara.
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