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Plant mineral nutrition is critical for agricultural productivity and for human nutrition; however, the availability of mineral elements is spatially and temporally heterogeneous in many ecosystems and agricultural landscapes. Nutrient imbalances trigger intricate signalling networks that modulate plant acclimation responses. One signalling agent of particular importance in such networks is phytomelatonin, a pleiotropic molecule with multiple functions. Evidence indicates that deficiencies or excesses of nutrients generally increase phytomelatonin levels in certain tissues, and it is increasingly thought to participate in the regulation of plant mineral nutrition. Alterations in endogenous phytomelatonin levels can protect plants from oxidative stress, influence root architecture, and influence nutrient uptake and efficiency of use through transcriptional and post-transcriptional regulation; such changes optimize mineral nutrient acquisition and ion homeostasis inside plant cells and thereby help to promote growth. This review summarizes current knowledge on the regulation of plant mineral nutrition by melatonin and highlights how endogenous phytomelatonin alters plant responses to specific mineral elements. In addition, we comprehensively discuss how melatonin influences uptake and transport under conditions of nutrient shortage.

Background: Male infertility is a major health concern in couples of childbearing ages. Nonobstructive azoospermia (NOA) is an extreme form of male infertility that affects ∼1% of adult men, and th...

Melatonin (MT) is a phytohormone-like substance and is profoundly involved in modulating nearly all aspects of plant development and acclimation to environmental stressors. However, there remain no studies about the effects of MT on tomato seed germination under salt stress. Here we reported that the overexpression of

Following meiotic recombination, each pair of homologous chromosomes acquires at least one crossover, which ensures accurate chromosome segregation and allows reciprocal exchange of genetic information. Recombination failure often leads to meiotic arrest, impairing fertility, but the molecular basis of recombination remains elusive. Here, we report a homozygous M1AP splicing mutation (c.1074 + 2T C) in patients with severe oligozoospermia owing to meiotic metaphase I arrest. The mutation abolishes M1AP foci on the chromosome axes, resulting in decreased recombination intermediates and crossovers in male mouse models. M1AP interacts with the mammalian ZZS (an acronym for yeast proteins Zip2-Zip4-Spo16) complex components, SHOC1, TEX11, and SPO16. M1AP localizes to chromosomal axes in a SPO16-dependent manner and colocalizes with TEX11. Ablation of M1AP does not alter SHOC1 localization but reduces the recruitment of TEX11 to recombination intermediates. M1AP shows cytoplasmic localization in fetal oocytes and is dispensable for fertility and crossover formation in female mice. Our study provides the first evidence that M1AP acts as a copartner of the ZZS complex to promote crossover formation and meiotic progression in males.

Polyploidy is a common mode of evolution in flowering plants. Both the natural tetraploid Thinopyrum elongatum and the diploid one from the same population show a diploid-like pairing in meiosis. However, debate on the chromosome composition and origin of the tetraploid Th. elongatum is ongoing. In the present study, we obtained the induced tetraploid Th. elongatum and found that the induced and natural tetraploids are morphologically close, except for slower development and lower seed setting. Using probes developed from single chromosome microdissection and a Fosmid library, obvious differentiations were discovered between two chromosome sets (E

PurposeChina is the world's largest consumer of pesticides. To increase the use efficiency and achieve more sustainable and environmentally friendly use of pesticides in China, it is crucial to understand why Chinese farmers use such a large amount of pesticides.Design/methodology/approachThe relationship between farm size and pesticide use was investigated by using national household-level panel data from 1995 to 2016.FindingFarms that are small and fragmented lead to the use of large amounts of pesticides in China. For a given crop type, three factors contribute to a negative relationship between farm size and pesticide use: the spillover effect from the use of pesticides by other farmers in the same village, the level of mechanization and the management ability of farmers. The first two factors play important roles in the cultivation of grain crops, while the last factor is the main reason why farmers with larger plots of land use fewer pesticides in the cultivation of vegetables. In addition, the effect of agricultural machinery services on reducing the use of pesticides is currently limited, and the service system in China is still insufficient, which has been pointed out that it is also due to the prevalence of small and fragmented farms.Originality/valueThe authors investigate and compare the farm size–pesticide use relationship in both grain and cash crop production. Moreover, the authors systematically explore and explain how farm size is related to a reduction in pesticide use in the cultivation of grain crops and cash crops. These results can help to better understand the role of land scale in pesticide use, lay a foundation for the formulation of policies to reduce pesticide use and provide valuable knowledge about pesticide use for other developing countries around the world.

Family with sequence similarity 181 (Fam181) is a gene family with two paralogues (Fam181a and Fam181b) found among vertebrates. Fam181a exhibits dynamic and stage-specific expression during murine embryo development. Furthermore, searching in the National Center for Biotechnology Information database revealed predominant expression of Fam181a in mouse and human testes, implying that it may have essential roles in spermatogenesis. In this study we investigated the in vivo function of Fam181a in mouse spermatogenesis and fertility by generating Fam181a–/– mice using clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas) 9 genome editing technology. The resulting Fam181a–/– mice exhibited normal growth and development. In addition, the mice were completely fertile, with no obvious differences in the testis-to-bodyweight ratio, epididymal sperm count or sperm motility compared with wild-type mice. Further examination of testicular and epididymal histology of Fam181a–/– mice found an intact seminiferous tubule structure and the presence of all types of germ cells, from spermatogonia to mature spermatozoa, similar to wild-type littermates. Similarly, analysis of meiotic prophase I progression revealed normal populations of each substage of prophase I in Fam181a+/+ and Fam181a–/– testes, suggesting that this gene is dispensable for male fertility. These negative findings will help avoid research overlap, save time and resources and allow researchers to concentrate on genes that are critical for male fertility and spermatogenesis.

Testis-specifically expressed genes are important for male reproduction according to their unique expression patterns. However, the functions of most of these genes in reproduction are unclear. Here, we showed that mouse 4930590J08Rik was a testis-specifically expressed gene. 4930590J08Rik knockout mice exhibited a delay in the first wave of spermatogenesis and a reduction of cauda epididymal sperm. Furthermore, knockout spermatozoa exhibited defective acrosome reactions and decreased progressive motility, which led to impaired in vivo fertilization. Transcriptome analysis of testes revealed that most of the differentially expressed genes in knockout testes were associated with metabolic processes. 4930590J08Rik knockout sperm exhibited oxidative phosphorylation deficiency and were highly dependent on increased anaerobic glycolysis to compensate for ATP demands. Taken together, the 4930590J08Rik-disrupted mouse partially mimics the phenotypes of human asthenospermia and oligozoospermia, which provides a new model for further understanding the pathogenesis of idiopathic male infertility.

During meiosis, at least one crossover must occur in each chromosome pair to ensure their accurate segregation. However, the mechanism of crossover formation is poorly understood. Here, we report a previously uncharacterized recombination protein, C12ORF40/REDIC1, essential for meiotic crossover formation. A homozygous frameshift mutation in C12orf40 was identified in two genetically unrelated infertile men with meiotic arrest. Subsequent analysis showed that REDIC1 forms discrete foci in the paired regions of homologous chromosomes depending on strand invasion. Mouse models mimicking the patients’ mutation showed reductions in crossover and bivalent formation, leading to spermatogenic failure. Notably, mutant spermatocytes displayed reduced numbers of MSH4 and TEX11 foci, accompanied by synaptic defects. Correspondingly, these phenotypes were also observed in our patients. Finally, biochemical results showed that the identified mutation impairs its ability to bind branched recombination intermediates. Therefore, our findings reveal a crucial role for C12ORF40/REDIC1 in meiotic crossover formation by stabilizing the recombination intermediates, providing prospective molecular targets for the clinical diagnosis and therapy of infertility.

The WRKY family is a large group of transcription factors found in higher plants; it plays an important role in many aspects of biological processes. However, there is very little information about this family in melon (Cucumis melo L.). In our research, 57 candidate WRKY genes in the melon genome were identified. According to their structural and phylogenetic features, the 57 CmWRKY genes were classified into three groups, I, II, and III, and the group II was further divided into five subgroups. Group I included 11 members that all have two conservative WRKY domains and a C2H2-type zinc finger motif; Group II contains 41 WRKY gene family members, that all have a WRKY domain and a C2H2-type zinc finger motif. Five members that all have a conservative WRKY domain and a C2HC-type zinc finger motif are classified as Group III. The expression of 16 selected melon WRKY genes was detected by quantitative real-time PCR after sprayed with salicylic acid (SA) or powdery mildew infection. qRT-PCR analysis showed that 16 CmWRKY genes exhibited distinct expression patterns upon powdery mildew infection, and the expression levels of nine genes were inhibited, and seven genes were induced. After being sprayed with SA, the expression levels of 11 genes were inhibited, and five genes were induced. The data here provide an important basis for further functional studies of the WRKY gene in melon resistance.