Objective  Genetic information and functions of trihelix factors in GT-1 critical to the growth, development, and resistance to abiotic stresses and plant growth regulator of tomato plants were investigated.

  Method  Bioinformatic techniques were applied to decipher the bio-evolutionary of GT-1 in tomato. RT-PCR was used to determine the expressions and responses to abiotic stresses and plant growth regulator of the gene.

  Result  (1) In tomato, GT-1 had 3 subfamily members, i.e., SlGT-21, SlGT-24, and SlGT-35. The evolutionary analysis indicated that those members differentiated functionally. (2) The 3 subfamily genes expressed in all tested tomato tissues with the highest level in the fruits, especially during the growing stage. It was speculated that SlGT-21 and SlGT-35 might share some common functionalities. (3) All 3 genes, particularly SlGT-24, could be suppressed by dehydration, and SlGT-21 and SlGT-35 more severely affected by salt stress. (4) The expressions of these genes were inhibited by GA(Gibberellin), EBR(Epihomobrassinolide), and MeJA (Methyl jasmonate); but those of SlGT-24 induced by ABA (Abscisic acid) and ACC(1-Aminocyclopropanecarboxylic acid), and SlGT-35 by ABA.

  Conclusion  Three GT-1 subfamily genes of tomato plants could be regulated by salt and/or dehydration stresses and were sensitive to hormonal stimulations.