DWARF TILLER1 regulates apical-basal pattern formation and proper orientation of rice embryos.

Body axis establishment is one of the earliest patterning events in plant embryogenesis. Asymmetric zygote division is critical for apical-basal axis formation in Arabidopsis (Arabidopsis thaliana). However, how the orientation of the cell division plane is regulated and its relation to apical-basal axis establishment and proper position of embryos in grasses remain poorly understood. By characterizing mutants of 3 rice (Oryza sativa) WUSCHEL HOMEOBOX9 (WOX9) genes, whose paralogs in Arabidopsis play essential roles in zygotic asymmetric cell division and cell fate determination, we found 2 kinds of independent embryonic defects: topsy-turvy embryos, in which apical-basal axis twists from being parallel to the longitudinal axis of the seed to being perpendicular; and organ-less embryos. In contrast to their Arabidopsis orthologs, OsWOX9s displayed dynamic distribution during embryo development. Both DWT1/OsWOX9A and DWL2/WOX9C play major roles in the apical-basal axis formation and initiation of stem cells. In addition, DWT1 has a distinct function in regulating the first few embryonic cell divisions to ensure the correct orientation of the embryo in the ovary. In summary, DWT1 acts in 2 steps during rice embryo pattern formation: the initial zygotic division, and with DWL2 to establish the main body axes and stem cell fate 2 to 3 d after pollination.

m6A demethylase OsALKBH5 is required for double-strand break formation and repair by affecting mRNA stability in rice meiosis.

N6-methyladenosine (m6A) RNA modification is the most prevalent messenger RNA (mRNA) modification in eukaryotes and plays critical roles in the regulation of gene expression. m6A is a reversible RNA modification that is deposited by methyltransferases (writers) and removed by demethylases (erasers). The function of m6A erasers in plants is highly diversified and their roles in cereal crops, especially in reproductive development essential for crop yield, are largely unknown. Here, we demonstrate that rice OsALKBH5 acts as an m6A demethylase required for the normal progression of male meiosis. OsALKBH5 is a nucleo-cytoplasmic protein, highly enriched in rice anthers during meiosis, that associates with P-bodies and exon junction complexes, suggesting that it is involved in regulating mRNA processing and abundance. Mutations of OsALKBH5 cause reduced double-strand break (DSB) formation, severe defects in DSB repair, and delayed meiotic progression, leading to complete male sterility. Transcriptome analysis and m6A profiling indicate that OsALKBH5-mediated m6A demethylation stabilizes the mRNA level of multiple meiotic genes directly or indirectly, including several genes that regulate DSB formation and repair. Our study reveals the indispensable role of m6A metabolism in post-transcriptional regulation of meiotic progression in rice.

A promoter polymorphism defines distinct roles in anther development for Col-0 and Ler-0 alleles of Arabidopsis ACYL-COA BINDING PROTEIN3.

Acyl-CoA-Binding Proteins (ACBPs) bind acyl-CoA esters and function in lipid metabolism. Although acbp3-1, the ACBP3 mutant in Arabidopsis thaliana ecotype Col-0, displays normal floral development, the acbp3-2 mutant from ecotype Ler-0 characterized herein exhibits defective adaxial anther lobes and improper sporocyte formation. To understand these differences and identify the role of ERECTA in ACBP3 function, the acbp3 mutants and acbp3-erecta (er) lines were analyzed by microscopy for anther morphology and high-performance liquid chromatography for lipid composition. Defects in Landsberg anther development were related to the ERECTA-mediated pathway because the progenies of acbp3-2 × La-0 and acbp3-1 × er-1 in Col-0 showed normal anthers, contrasting to that of acbp3-2 in Ler-0. Polymorphism in the regulatory region of ACBP3 enabled its function in anther development in Ler-0 but not Col-0 which harbored an AT-repeat insertion. ACBP3 expression and anther development in acbp3-2 were restored using ACBP3pro (Ler)::ACBP3 not ACBP3pro (Col)::ACBP3. SPOROCYTELESS (SPL), a sporocyte formation regulator activated ACBP3 transcription in Ler-0 but not Col-0. For anther development, the ERECTA-related role of ACBP3 is required in Ler-0, but not Col-0. The disrupted promoter regulatory region for SPL binding in Col-0 eliminates the role of ACBP3 in anther development.

Global food expenditure patterns diverge between low-income and high-income countries.

Globalization, income growth and changing cultural trends are believed to prompt consumers in low-income countries to adopt the more affluent diet of high-income countries. This study investigates the convergence of food expenditure patterns worldwide, focusing on total food expenditure, raw food categories and ultra-processed foods and beverages across more than 90 countries over the past decades. Contrary to prior belief, we find that food expenditure patterns of lower-income countries do not universally align with those of higher-income nations. This trend is evident across most raw food categories and ultra-processed foods and beverages, as the income level of a country continues to play a crucial role in determining its food expenditure patterns. Importantly, expenditure patterns offer estimates rather than a precise idea of dietary intake, reflecting consumer choices shaped by economic constraints rather than exact dietary consumption.

The RING Domain of Rice HEI10 is Essential for Male, But Not Female Fertility.

HEI10 is a conserved E3 ubiquitin ligase involved in crossover formation during meiosis, and is thus essential for both male and female gamete development. Here, we have discovered a novel allele of HEI10 in rice that produces a truncated HEI10 protein missing its N-terminal RING domain, namely sh1 (shorter hei10 1). Unlike previously reported hei10 null alleles that are completely sterile, sh1 exhibits complete male sterility but retains partial female fertility. The causative sh1 mutation is a 76 kb inversion between OsFYVE4 and HEI10, which breaks the integrity of both genes. Allelic tests and complementation assays revealed that the gamete developmental defects of sh1 were caused by disruption of HEI10. Further studies demonstrated that short HEI10 can correctly localise to the nucleus, where it could interact with other proteins that direct meiosis; expressing short HEI10 in hei10 null lines partially restores female fertility. Our data reveal an intriguing mutant allele of HEI10 with differential effects on male and female fertility, providing a new tool to explore similarities and differences between male and female meiosis.

Exploration of new models for primary dysmenorrhea treatment: low-power visible-light-activated photodynamic therapy and oral contraceptives.

Background: Primary dysmenorrhea (PD) is one of the most common reasons that affect the life quality of women during childbearing age. This research aims to explore the efficacy and curative effect characteristics of oral contraceptives and low-power visible-light-activated photodynamic therapy (PDT). Besides investigating the possible mechanism of PDT, we expected to find a treatment model with better efficacy and fewer side effects. Method: It was a multicenter, randomized, parallel-controlled study. Eligible participants were randomly assigned to three groups: placebo group, oral contraceptive (Marvelon) group, and the PDT group. They were treated continuously for three menstrual cycles and followed up for two cycles after treatment. The scores of the visual analog scale (VAS) and the concentration of pain-related small molecules in blood before and after treatment were recorded in each group, which can evaluate the therapeutic characteristics of different treatments. Result: Both Marvelon and PDT were effective. The effect of Marvelon appears quickly which can significantly relieve symptoms at the beginning, while PDT shows a relatively slow role. There was no significant difference in the final efficacy two cycles after treatment. The therapeutic effect was achieved by reducing the concentrations of prostaglandin 2 (PGE2) and endothelin (ET) in the blood. Conclusion: Marvelon and PDT are effective methods for the treatment of PD. The long-term efficacy of the two is similar, while the therapeutic characteristics and the side effects are different. Patients can choose the suitable way according to their individual needs.