Melatonin (N-acetyl-5-methoxytryptamine) is a nontoxic biological molecule produced in a pineal gland of animals and different tissues of plants. It is an important secondary messenger molecule, playing a vital role in coping with various abiotic and biotic stresses. Melatonin serves as an antioxidant in postharvest technology and enhances the postharvest life of fruits and vegetables. The application of exogenous melatonin alleviated reactive oxygen species and cell damage induced by abiotic and biotic stresses by means of repairing mitochondria. Additionally, the regulation of stress-specific genes and the activation of pathogenesis-related protein and antioxidant enzymes genes under biotic and abiotic stress makes it a more versatile molecule. Besides that, the crosstalk with other phytohormones makes inroads to utilize melatonin against non-testified stress conditions, such as viruses and nematodes. Furthermore, different strategies have been discussed to induce endogenous melatonin activity in order to sustain a plant system. Our review highlighted the diverse roles of melatonin in a plant system, which could be useful in enhancing the environmental friendly crop production and ensure food safety.

Exploring the molecular foundation of the gene-regulatory systems underlying agronomic parameters or/and plant responses to both abiotic and biotic stresses is crucial for crop improvement. Thus, transcription factors, which alone or in combination directly regulated the targeted gene expression levels, are appropriate players for enlightening agronomic parameters through genetic engineering. In this regard, homeodomain leucine zipper (HD-ZIP) genes family concerned with enlightening plant growth and tolerance to environmental stresses are considered key players for crop improvement. This gene family containing HD and LZ domain belongs to the homeobox superfamily. It is further classified into four subfamilies, namely HD-ZIP I, HD-ZIP II, HD-ZIP III, and HD-ZIP IV. The first HD domain-containing gene was discovered in maize cells almost three decades ago. Since then, with advanced technologies, these genes were functionally characterized for their distinct roles in overall plant growth and development under adverse environmental conditions. This review summarized the different functions of HD-ZIP genes in plant growth and physiological-related activities from germination to fruit development. Additionally, the HD-ZIP genes also respond to various abiotic and biotic environmental stimuli by regulating defense response of plants. This review, therefore, highlighted the various significant aspects of this important gene family based on the recent findings. The practical application of HD-ZIP biomolecules in developing bioengineered plants will not only mitigate the negative effects of environmental stresses but also increase the overall production of crop plants.

Depression, a mental illness characterized by persistent feeling of sadness and loss of interest, has been a serious health problem worldwide. Manipulation of the microbiota by probiotics and prebiotics represents a novel emerging strategy for the treatment of various psychiatric disorders such as major depressive disorders. Here, we show that one water-soluble polysaccharide from Ginkgo biloba leaves (GPS) reduced stress-induced depression and reversed gut dysbiosis. Similar to the antidepressant paroxetine, GPS significantly reduced the immobility times in the tail suspension test (TST) and forced swimming test (FST) and anxiety-like behavior in the open field test (OFT). Consistent with the improvement of depression-like behavior above, GPS mice had elevated serotonin and dopamine levels in multiple brain regions including the hippocampus, cerebral cortex and olfactory bulb, relative to unpredictable chronic mild stress (UCMS) treatment mice. GPS treatment could alleviate the stress-induced reduction in the density of serotonin-positive and dopamine-positive cells. Fecal microbiome transplant (FMT) combined with antibiotic treatment showed that the anti-depressant activity of GPS had a causal relationship with intestinal microbes. By performing a pyrosequencing-based analysis of bacterial 16S rRNA (V3 + V4 region) in fecal of the mice, the results showed that GPS reversed depression-associated gut dysbiosis and increased the richness of Lactobacillus species which has been proven to be a path to relieve depression. Our results demonstrated that the polysaccharide from Ginkgo biloba leaves might be a promising pharmacotherapeutic candidate for treating depression.

Acute liver injury (ALI) is a globally important public health issue that, when severe, rapidly progresses to acute liver failure, seriously compromising the life safety of patients. The pathogenesis of ALI is defined by massive cell death in the liver, which triggers a cascade of immune responses. Studies have shown that the aberrant activation of the nod-like receptor protein 3 (NLRP3) inflammasome plays an important role in various types of ALI and that the activation of the NLRP3 inflammasome causes various types of programmed cell death (PCD), and these cell death effectors can in turn regulate NLRP3 inflammasome activation. This indicates that NLRP3 inflammasome activation is inextricably linked to PCD. In this review, we summarize the role of NLRP3 inflammasome activation and PCD in various types of ALI (APAP, liver ischemia reperfusion, CCl₄, alcohol, Con A, and LPS/D-GalN induced ALI) and analyze the underlying mechanisms to provide references for future relevant studies.

The dwarf or compact plant architecture is an important trait in plant breeding. A number of genes controlling plant height have been cloned and functionally characterized which often involve in biosynthesis or signaling of plant hormones such as brassinosteroids (BRs). No genes for plant height or vine length have been cloned in cucurbit crops (family Cucurbitaceae). From an EMS-induced mutagenesis population, we identified a super compact (SCP) mutant C257 which was extremely dwarf due to practically no internode elongation. Under dark growing condition, C257 did not undergo skotomorphogenesis and its mutant phenotype could be rescued with exogenous application of brassinolide, suggesting SCP might be a BR-deficient mutant. Segregation analysis revealed a single recessive gene scp-1 that was responsible for the SCP mutation. Map-based cloning combined with a modified MutMap identified CsCYP85A1, a member of the plant cytochrome P450 monooxygenase gene family, as the most possible candidate gene for scp-1, which encodes a BR-C6-oxidase in the BR biosynthesis pathway. We show that a SNP within the second exon of scp-1 candidate gene caused the SCP phenotype. Three copies of the CsCYP85A gene are present in the cucumber genome, but only the scp-1/CsCYP85A1 gene seemed active. The expression of CsCYP85A1 was higher in flowers than in the leaves and stem; its expression in the wild type was feedback regulated by brassinolide application. Its expression was reduced in C257 as compared with the wild type. This was the first report of map-based cloning of a plant height gene in cucurbit crops. The research highlighted the combined use of linkage mapping, an improved MutMap method and allelic diversity analysis in natural populations in quick cloning of simply inherited genes in cucumber. The roles of CsCYP85A1 in regulation of internode elongation in cucumber was discussed.

Grass pea (Lathyrus sativus L.) is an important legume crop grown mainly in South Asia and Sub-Saharan Africa. This underutilized legume can withstand harsh environmental conditions including drought and flooding. During drought-induced famines, this protein-rich legume serves as a food source for poor farmers when other crops fail under harsh environmental conditions; however, its use is limited because of the presence of an endogenous neurotoxic nonprotein amino acid β-N-oxalyl-l-α,β-diaminopropionic acid (β-ODAP). Long-term consumption of Lathyrus and β-ODAP is linked to lathyrism, which is a degenerative motor neuron syndrome. Pharmacological studies indicate that nutritional deficiencies in methionine and cysteine may aggravate the neurotoxicity of β-ODAP. The biosynthetic pathway leading to the production of β-ODAP is poorly understood, but is linked to sulfur metabolism. To date, only a limited number of studies have been conducted in grass pea on the sulfur assimilatory enzymes and how these enzymes regulate the biosynthesis of β-ODAP. Here, we review the current knowledge on the role of sulfur metabolism in grass pea and its contribution to β-ODAP biosynthesis. Unraveling the fundamental steps and regulation of β-ODAP biosynthesis in grass pea will be vital for the development of improved varieties of this underutilized legume.