Analysis of FsTyDC1 Gene from Forsythia suspensa in Response to Drought and Salt Stress Treatment

<b>Background</b>: <i>Forsythia suspensa</i> (Thunb.) Vahl is a perennial deciduous shrub of the Oleaceae family. Its dried mature fruits are used as medicine and hold an important position in traditional Chinese medicine. Tyrosine decarboxylase (TyDC) is a key enzyme involved in the synthesis of dopamine in Forsythia suspensa. At the same time, it also affects the growth and development of this species under biotic stress. <b>Methods</b>: This study examined the expression and function of <i>FsTyDC1</i> under drought and salt stress. The <i>TyDC</i> gene identified in <i>F. suspensa</i>, termed <i>FsTyDC1</i>, has an open reading frame (ORF) of 1518 bp. <b>Results</b>: qRT-PCR and subcellular localization analyses indicated that <i>FsTyDC1</i> is highly expressed in <i>F. suspensa</i> fruit and its protein is located in the cytoplasm. The gene was silenced using a pTRV2-FsPDS/<i>FsTyDC1</i> vector with virus-induced gene silencing. Following exposure to drought and salt stress, the leaves of <i>FsTyDC1</i>-silenced plants exhibited increased curling and wilting. <b>Conclusions</b>: The results indicate that <i>FsTyDC1</i> responds to both salt and drought stress, which provides a foundation for further investigation into the function of <i>FsTyDC1</i>.