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Saline-alkali stress is a major abiotic stress that limits plant growth, yield, and geographical distribution. Alfalfa is a perennial legume with the largest planting area in the world because of its high protein content, good palatability, and long utilization life. However, saline-alkali stress seriously affects alfalfa yield and quality. To better understand the saline-alkali stress response mechanisms of alfalfa, an isobaric tags proteomics method was used to compare and analyse alfalfa under saline-alkali stress for 0, 1, and 7 days, and 126 (1 vs. 0 days) and 1869 (7 vs. 0 days) differentially abundant proteins (DAPs) were found. Through integrative analysis with differentially expressed genes (DEGs), we found correlated DEGs-DAPs of RNA and protein with similar expression trends at the mRNA and protein levels; these were mainly involved in ABA and Ca

Ethyl acetate is an important flavor element that is a vital component of baijiu. To date, the transcription factors that can help identify the molecular mechanisms involved in the synthesis of ethyl acetate have not been studied. In the present study, we sequenced and assembled the Wickerhamomyces anomalus strain YF1503 transcriptomes to identify transcription factors. We identified 307 transcription factors in YF1503 using high-throughput RNA sequencing. Some transcription factors, such as C2H2, bHLH, MYB, and bZIP, were up-regulated, and these might play a role in ethyl acetate synthesis. According to the trend of ethyl acetate content, heat map results and STEM, twelve genes were selected for verification of expression levels using quantitative real-time PCR. This dynamic transcriptome analysis presents fundamental information on the transcription factors and pathways that are involved in the synthesis of ethyl acetate in aroma-producing yeast. Of significant interest is the discovery of the roles of various transcription factor genes in the synthesis of ethyl acetate.

MsCML46 enhances tolerance to abiotic stresses through alleviating osmotic stress and oxidative damage by regulating the expression of stress-related genes to optimize osmolytes levels and antioxidant enzyme activity in transgenic tobacco. Abiotic stresses are major environmental factors that constraint crop productivity worldwide. Various stimuli regulate intracellular calcium levels and calcium-mediated signal transduction, and cellular responses. Ca2+ signals are perceived by different Ca2+ receptors. Calmodulin-like protein (CML) is one of the best-characterized Ca2+ sensors which shares sequence similarity with highly conserved calmodulin (CaM) ubiquitously expressed in plants. Currently, the molecular and physiological functions of CMLs are largely unknown. In this study, the MsCML46 was characterized in alfalfa (Medicago sativa cv. Zhaodong) under freezing stress. Results showed that MsCML46 was localized to the cytoplasm of Arabidopsis, and its expression was strongly elevated by cold, drought, salt, saline-alkali, and ABA treatments. Overexpressing MsCML46 in tobacco enhanced tolerance to freezing, drought, and salt stresses as evidenced by improved contents of osmotic regulatory solutes and antioxidant enzyme activity but decreased reactive oxygen species (ROS) accumulation. Furthermore, cold, drought, and salt stresses increased the expression of stress-related genes in transgenic tobacco. MsCML46 binds free Ca2+ to promote signal transduction and maintain higher K+/Na+ ratio. In this way, it protects intracellular homeostasis under sodium ion toxicity. These results suggest that MsCML46 plays a crucial role in resisting abiotic stresses and can be exploited in genetic engineering for crops.

The amino acid/auxin permease (AAAP) gene family plays a significant role in the long-distance amino acid transport and is involved in plant stress responses and various developmental processes. The functions of the AAAP family have been extensively discussed in multiple organisms, whereas detailed information of this family in strawberry (Fragaria vesca) has not been reported yet. In this study, we identified 45 AAAP genes in the strawberry genome. Phylogenetic analysis indicated that AAAPs from strawberry and Arabidopsis were clustered into eight groups. Expression analysis of the AAAP family showed that AAAP genes were expressed differentially in different developmental stages of flower and fruit, and were significantly induced after Colletotrichum gloeosporioides infection. Our study provides a comprehensive understanding of the strawberry AAAP family and demonstrates their potential roles in disease resistance, providing more reference for further research.

MsCBL4 expression in tobacco enhanced its salt and saline–alkali stress tolerance by regulating calcium accumulation in roots, indicating the important role of calcium metabolism in plant saline–alkali stress tolerance The calcineurin B–like (CBL) family of proteins play important roles in plant abiotic stress tolerance and signal transduction. CBL4 is known to participate in the Salt Overly Sensitive pathway; however, little is currently known regarding the mechanisms underlying the response of CBL4 to saline–alkali stress. In this study, we cloned and characterized the alfalfa MsCBL4 gene. We found that MsCBL4 showed the highest expression in root tissues and was induced by salt and saline–alkali stress, with the latter causing higher induction. Overexpression of MsCBL4 in tobacco enhanced salt and saline–alkali stress tolerance and reduced the Na+/K+ ratio in roots of transgenic lines. Salt (30 and 300 mM NaCl) and saline–alkali (30 mM NaHCO3) stress assays performed for MsCBL4 transgenic tobacco lines revealed a substantial influx of sodium ions in roots under saline–alkali stress and indicated that the expression of MsCBL4 had little influence on sodium ion content reduction. In contrast, in roots subjected to saline–alkali stress, calcium accumulation occurred and was significantly enhanced by the overexpression of MsCBL4. Physiological and biochemical analyses indicated that MsCBL4 plays an important role in saline–alkali stress tolerance via its influence on the regulation of calcium transport and accumulation. These results provide novel insights into the saline–alkali stress tolerance mechanisms of plants.

The teosinte branched1, cycloidea, and proliferating cell factor family (TCP) proteins, plant-specific transcription factors, are involved in the regulation of plant development; however, the TCP gene family of legumes has been based primarily on a single crop. Here, a total of 55, 22, 26, 21, and 25 genes containing the VQ motif were identified from the genomes of Glycine max, Cicer arietinum, Phaseolus vulgaris, Medicago truncatula, and Lotus japonicus, respectively. Based on the phylogenetic analysis, we divided these TCP genes into three distinct subfamilies: PCF, CYC/TB1, and CIN. The conserved domain analysis indicated that the TCP gene family members contain the bHLH and R domains. The TCP genes from the same evolutionary branches of legumes shared similar motifs and structures. The promoter analysis revealed that cis-elements were related to stress responses, phytohormone responses, and physical and reproductive growth regulation. In addition, the TCP genes presented different expression patterns in the five legumes. Most of them showed specific expression patterns during development. The results of qRT-PCR indicated that the TCP genes played regulatory roles in both salt and drought stresses. The present study provides novel and detailed information regarding the legume TCP gene family, which aids in functional characterisation of the TCP genes in other plants.

Abiotic stresses restrict the productivity and quality of agricultural crops. Glutathione S-transferase (GST) utilizes glutathione to scavenge reactive oxygen species (ROS) that result from abiotic stresses. This study aimed to determine the expression pattern of the MsGSTU8 gene and its effects on saline-alkali tolerance. MsGSTU8, from alfalfa (Medicago sativa ‘Zhaodong’), was transformed into transgenic tobacco (Nicotiana tabacum) and overexpressed to determine its effects on saline-alkali tolerance. The gene products in alfalfa localized to the cytoplasm and the transcript levels were higher in the leaves than the roots and stems. Expression was strongly induced by cold, drought, salt and saline-alkali stresses as well as abscisic acid (ABA) treatments. The transgenic tobacco lines had significantly higher transcription levels of the abiotic stress-related genes and higher GST activity than the wild types. Transgenic tobacco lines with saline-alkali treatments maintained their chlorophyll content, showed improved antioxidant enzyme activity and soluble sugar levels, reduced ion leakage, O2.−, H2O2 accumulation and malondialdehyde content. Our results indicate that overexpression of MsGSTU8 could improve resistance to saline-alkali stresses by decreasing the accumulation of ROS and increasing the levels of antioxidant enzymes. Furthermore, they suggest that MsGSTU8 could be utilized for transgenic crop plant breeding., Summary: The glutathione S-transferase gene of Medicago sativa can effectively alleviate osmotic and oxidative damage induced by saline-alkali stress in transgenic tobacco.