Analysis of Expression Characteristics of Scarecrow-Like Gene Stsl-1 Elicited by Exogenous Hormone and Ralstonia solanacearum Infection in Potato

摘要

In higher plants, Scarecrow-like protein (SCL) is a transcription factor belonging to the GRAS family. It regulates root growth and cell cycle and also mediates resistance to environmental stresses. To investigate the function of SCL gene in response to plant pathogen infection, the full-length of potato (Solanum tuberosum) SCL gene named Stsl-1 was cloned. Bioinfromatcal analysis of the gene revealed that Stsl-1 consists of 2,139 bp; including a 1,614 bp open reading frame that encodes a protein with 537 amino acids. Stsl-1 is highly similar to Scarecrow-like protein 21 (SCL21) in potato and other Solanaceae species. Quantitative real-time polymerase chain reaction assays indicated that Stsl-1 was induced by Ralstonia solanacearum and up-regulated to varying extents by specific concentrations of exogenous phytohormones, including salicylic acid (SA), methyl jasmonate (MeJA) and abscisic acid (ABA). Examination of tissue localization suggested that Stsl-1 was primarily expressed in specific tissues (the phloem of the stem and leaf vascular systems). Furthermore, the subcellular localization of Stsl-1 in Nicotiana benthamiana leaves proved that the encoded protein was mainly localized in the cell nucleus. The results of the study should lay down the foundation for future research on the functional characterization of the SCL in potato plants.