We previously showed that the N6-methyladenosine (m⁶A) mRNA methylase is essential during Arabidopsis thaliana embryonic development. We also demonstrated that this modification is present at varying levels in all mature tissues. However, the requirement for the m⁶A in the mature plant was not tested. Here we show that a 90% reduction in m⁶A levels during later growth stages gives rise to plants with altered growth patterns and reduced apical dominance. The flowers of these plants commonly show defects in their floral organ number, size, and identity. The global analysis of gene expression from reduced m⁶A plants show that a significant number of down-regulated genes are involved in transport, or targeted transport, and most of the up-regulated genes are involved in stress and stimulus response processes. An analysis of m⁶A distribution in fragmented mRNA suggests that the m⁶A is predominantly positioned toward the 3′ end of transcripts in a region 100–150 bp before the poly(A) tail. In addition to the analysis of the phenotypic changes in the low methylation Arabidopsis plants we will review the latest advances in the field of mRNA internal methylation

The excessive content of heavy metals and the deficiency of beneficial trace elements in cereals have threatened global food security and human health. As important metal transporters, Natural resistance-associated macrophage proteins (Nramps) are involved in the absorption and transport of various metal ions in plants, including beneficial elements and hazardous heavy metals, yet little is known about their roles in foxtail millet. In this study, 12 Nramps were identified in foxtail millet genome and divided into three clades. Expansion and functional differentiation of SiNramp gene family is evident in the high proportion of gene duplication as well as the diversity in protein structure and expression characteristics. The SiNramp genes exhibited different response patterns to Cd stress in different tissues. Based on the integration of ionome, RNA-seq and orthologous analysis, the association of SiNramp genes with the accumulation of different metal ions was investigated, and the possible functions of several SiNramp genes were predicted, such as SiNramp6 and SiNramp12. In general, this study provides a comprehensive theoretical framework for the study of Nramp genes in foxtail millet and other minor gramineous crops, which will lay a foundation for further research on the mechanism of metal transport and accumulation.

Background: Broomcorn millet (Panicum miliaceum L.), a drought-tolerant C4 crop, is crucial for agricultural resilience in arid regions. Lipoxygenases (LOXs), key enzymes in plant stress responses, have not been studied in broomcorn millet. This study aimed to identify LOX genes in broomcorn millet and elucidate their role in drought tolerance. Methods: We employed bioinformatics and physiological analyses to identify LOX genes in broomcorn millet. Expression profiles were assessed in different organs, and drought stress responses were evaluated in tolerant (HSZ, YXDHM) and sensitive (YS10) varieties. Antioxidant enzyme activities (SOD, POD, CAT) and malondialdehyde (MDA) levels were measured. Results: Twelve LOX genes were identified, classified into three subfamilies, and mapped across seven chromosomes. These genes contained stress-responsive cis-elements and showed organ-specific expression, with PmLOX5 exhibiting no detectable expression. Under drought stress, tolerant varieties showed elevated antioxidant activities and reduced MDA accumulation. PmLOX2, a homolog of Arabidopsis AtLOX1/AtLOX5, was significantly induced in tolerant varieties, correlating with enhanced antioxidant capacity and reduced oxidative damage. Conclusions:PmLOX genes, particularly PmLOX2, play a pivotal role in drought tolerance by modulating ROS scavenging and membrane protection. This study provides a foundation for leveraging LOX genes to improve drought resilience in broomcorn millet and related crops.

WUSCHEL-related homeobox (WOX) transcription factors are unique to plants and play pivotal roles in plant development and stress responses. In this investigation, we acquired protein sequences of foxtail millet WOX gene family members through homologous sequence alignment and a hidden Markov model (HMM) search. Utilizing conserved domain prediction, we identified 13 foxtail millet WOX genes, which were classified into ancient, intermediate, and modern clades. Multiple sequence alignment results revealed that all WOX proteins possess a homeodomain (HD). The SiWOX genes, clustered together in the phylogenetic tree, exhibited analogous protein spatial structures, gene structures, and conserved motifs. The foxtail millet WOX genes are distributed across 7 chromosomes, featuring 3 pairs of tandem repeats: SiWOX1 and SiWOX13, SiWOX4 and SiWOX5, and SiWOX11 and SiWOX12. Collinearity analysis demonstrated that WOX genes in foxtail millet exhibit the highest collinearity with green foxtail, followed by maize. The SiWOX genes primarily harbor two categories of cis-acting regulatory elements: Stress response and plant hormone response. Notably, prominent hormones triggering responses include methyl jasmonate, abscisic acid, gibberellin, auxin, and salicylic acid. Analysis of SiWOX expression patterns and hormone responses unveiled potential functional diversity among different SiWOX genes in foxtail millet. These findings lay a solid foundation for further elucidating the functions and evolution of SiWOX genes.

Carotenoids are important compounds of quality and coloration within sweet potato storage roots, but the mechanisms that govern the accumulation of these carotenoids remain poorly understood. In this study, metabolomic and transcriptomic analyses of carotenoids were performed using young storage roots (S2) and old storage roots (S4) from white-fleshed (variety S19) and yellow-fleshed (variety BS) sweet potato types. S19 storage roots exhibited significantly lower total carotenoid levels relative to BS storage roots, and different numbers of carotenoid types were detected in the BS-S2, BS-S4, S19-S2, and S19-S4 samples. β-cryptoxanthin was identified as a potential key driver of differences in root coloration between the S19 and BS types. Combined transcriptomic and metabolomic analyses revealed significant co-annotation of the carotenoid and abscisic acid (ABA) metabolic pathways, PSY (phytoene synthase), CHYB (β-carotene 3-hydroxylase), ZEP (zeaxanthin epoxidase), NCED3 (9-cis-epoxycarotenoid dioxygenase 3), ABA2 (xanthoxin dehydrogenase), and CYP707A (abscisic acid 8’-hydroxylase) genes were found to be closely associated with carotenoid and ABA content in these sweet potato storage roots. The expression patterns of the transcription factors OFP and FAR1 were associated with the ABA content in these two sweet potato types. Together, these results provide a valuable foundation for understanding the mechanisms governing carotenoid biosynthesis in storage roots, and offer a theoretical basis for sweet potato breeding and management.