Agropyron mongolicum Keng is a diploid perennial grass of triticeae in gramineae. It has strong drought resistance and developed roots that can effectively fix the soil and prevent soil erosion. GDSL lipase or esterases/lipase has a variety of functions, mainly focusing on plant abiotic stress response. In this study, a GDSL gene from A. mongolicum, designated as AmGDSL1, was successfully cloned and isolated. The subcellular localization of the AmGDSL1 gene (pCAMBIA1302-AmGDSL1-EGFP) results showed that the AmGDSL1 protein of A. mongolicum was only localized in the cytoplasm. When transferred into tobacco (Nicotiana benthamiana), the heterologous expression of AmGDSL1 led to enhanced drought tolerance. Under drought stress, AmGDSL1 overexpressing plants showed fewer wilting leaves, longer roots, and larger root surface area. These overexpression lines possessed higher superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and proline (PRO) activities. At the same time, the malondialdehyde (MDA) content was lower than that in wild-type (WT) tobacco. These findings shed light on the molecular mechanisms involved in the GDSL gene’s role in drought resistance, contributing to the discovery and utilization of drought-resistant genes in A. mongolicum for enhancing crop drought resistance.

Pigmented potatoes (Solanum tuberosum L.) are rich in anthocyanin, which have antioxidantiy and play an important role in health and medical. Nevertheless, the regulation mechanism of anthocyanins in purple potato at different growth stages remain unclear. In this study, through using the high-throughput sequencing and systematic bioinformatics analysis, a total of 7,176 significantly different expressed genes (DEGs) were discovered from the purple potato Huasong 66 tubers at different developmental stages. Through GO and KEGG enrichment analysis, it was found that, 43 DEGs were mainly enriched in phenylpropanoid biosynthesis, flavonoid biosynthesis, and phenylalanine metabolism, which biological processes are closely related to anthocyanin biosynthesis. The quantitative RT-PCR were verified the reliability of transcriptome data. We demonstrated that DEGs or transcription factors (TFs) which related to flavonoid metabolism were involved in the anthocyanins biosynthesis, such as the protein-coding genes PAL, CHS, CHI, 4CL, F3H, UFGT, LAR, and the TFs MYB, bHLH, and HY5. The key genes involved in anthocyanin synthesis in potato tubers were identificated, it provides new insights for molecular breeding new cultivars. These results are valuable for improving the anthocyanin in potato.

Drought stress is one of the main factors limiting the high yield and quality of potatoes. Arabinogalactan proteins (AGPs) are an important class of glycoproteins widely present in the cell walls, plasma membranes, and extracellular matrices of higher plants. Among them, fasciclin-like arabinogalactan proteins (FLAs) are involved in plant development, stress responses, and hormone signal regulation. However, little is known about the FLAs gene in potatoes. Based on transcriptome sequencing data, this study screened a drought stress-related candidate FLA gene (StFLA4) through bioinformatics and expression analysis in potatoes. qRT-PCR analysis showed that StFLA4 was induced by drought stress, and its expression decreased with the extension of stress time. Moreover, the relative expression level of StFLA4 in the drought-resistant variety “Kexin 1” was lower than in the drought-sensitive variety “Atlantic”. The StFLA4 protein was located in the cell membrane and interacted with nineteen proteins, mainly related to response to environmental stimulus, cellular response to abiotic stimulus, and cell maturation. After heterologous overexpression of StFLA4 in tobacco, the transgenic plants showed more withered leaves than the wild-type tobacco under drought stress. During the drought stress period, the expression level of StFLA4 in the transgenic plants significantly decreased, and the activity of SOD and POD was significantly lower than that of WT. However, the MDA content was higher than that of WT. These results indicated that StFLA4 negatively regulates the response to drought stress. In addition, in the germination test of potato “Variety V7” tubers, it was found that the variation tendency of StFLA4 expression was along with the concentration of arabinogalactan proteins, and it may participate in the regulation of potato tuber germination. This study lays the foundation for elucidating the function and expression pattern of StFLA4 response to drought stress and tuber germination in potatoes.