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Tribulus terrestris L. is an annual herbaceous medicinal plant of Zygophyllaceae, which is cultivated commercially in China. Subrotund or irregular gray, sunken, necrotic spots ranging from 2 to 9 mm were observed on diseased leaves of T. terrestris landrace in Fushun County, Liaoning Province of northeast China in July 2021, with more than 32% of the plants being infected in a 18-ha field. The symptoms first appeared on older leaves and gradually spread to younger leaves. The lesions developed a white center gradually and became perforated; multiple lesions could coalesce (Fig. 1). Ten symptomatic leaves were collected and the diseased tissues were cut into small pieces, immersed in 1% NaOCl for 2 min, rinsed three times with sterile water, and placed on acidified potato dextrose agar (PDA) in Petri dishes at 25°C in darkness. Fifteen suspected Colletotrichum single-spore fungal isolates (JL1 to JL15) with consistent morphological characteristics were obtained, and isolate JL6 was selected for identification and pathogenicity testing. Colonies on PDA were flat with an entire margin, dense and white at first, then became dark gray with numerous black microsclerotia and formed a concentric circular pattern with aging. Conidia were single-celled, sickle-curved with a tapered tip and truncate base, ranging from 16.46 to 20.26 μm in length and 2.81 to 3.96 μm in width (n=100). Setae were dark brown, septate, straight with a slightly acute tip, 75.45 to 135.63×3.19 to 4.95 μm in size. Appressoria were dark brown, round or irregular, mostly in groups. All characteristics were consistent with the descriptions of C. truncatum (Damm et al. 2009). Further confirmation of the identification was determined according to methods described previously (Damm et al. 2009). The rDNA internal transcribed spacer region (OP364400, 585 bp), and actin (OP380867, 290 bp), beta-tubulin (OP380868, 498 bp), chitin synthase 1 (OP380869, 277 bp), glyceraldehyde-3-phosphate dehydrogenase (OP380870, 280 bp), and histone (OP380871, 411 bp) genes were amplified by PCR and sequenced (Carbone and Kohn 1999; Glass and& Donaldson 1995; Guerber et al. 2003; O'Donnell and Cigelnik 1997). BLAST results showed 98-100% similarity at 85-97% coverage compared to the corresponding sequences of the type strain CBS 151.35 (GU227862, GU227960, GU228156, GU228352, GU228254, and GU228058). Phylogenetic analysis combining all loci revealed that the isolate JL6 and the type strains of C. truncatum clustered in one group (Fig. 2). One-year-old healthy seedlings of T. terrestris (cultivar: landrace) were used for pathogenicity test. Suspension (1×105 conidia/mL) of isolate JL6 was sprayed on ten seedlings, and ten seedlings sprayed with sterilized distilled water were used as the control. Three replicates were performed on each treatment. All plants were kept at 28±1°C (12 h photoperiod), and were evaluated after 7 days. The inoculated plants showed lesions on the leaf surface, similar to those in the field, and the control remained symptomless. The pathogen was successfully reisolated and identified using the methods mentioned above. To our knowledge, this is the first report of C. truncatum causing anthracnose on T. terrestris, which will provide valuable information for designing strategies to manage anthracnose on T. terrestris.

American ginseng (Panax quinquefolium) is a valuable medicinal plant that is commercially cultivated in China. In May 2020, Sclerotinia root rot of American ginseng was observed on 4-year-old plants in Fusong County in northeastern China, which is the most important part of the country for American ginseng cultivation. The pathogen only infected the tuberous ginseng roots, with sclerotia tightly attached to the root surface. Infected roots, which were brownish and had a watery soft rotted appearance (Fig. 1), eventually became hollow and filled with sclerotia. There were no significant changes to the aboveground plant parts during the initial infection stage, but as the disease progressed, the foliage became discolored and wilted because of the damaged roots. More than 31% of the plants in a 30-ha field were infected. Symptomatic roots were collected and sclerotia were removed from the diseased tissue, immersed in 1% NaClO for 1 min, rinsed three times with sterile water, and placed on acidified potato dextrose agar (PDA) in Petri dishes. After an incubation in darkness at 20 °C for 2-3 days, 21 suspected Sclerotinia isolates were obtained. Isolates JH1 and JH2 were randomly selected for identification. On PDA, colonies produced sparse, white, and cottony aerial mycelia (i.e., wool-like appearance), with septate, branched, and hyaline hyphae. Within 4 days of incubation, the PDA surface was covered with white hyphae. Small and white sclerotial primordia formed 3 days later and were irregularly distributed in the middle and along the edge of the Petri dish. After maturing, the hardened and black sclerotia had an irregular shape and size, ranging from 1.4 × 1.5 to 4.1 × 7.5 mm (n = 50). Most of the sclerotia developed separately, with approximately 15-25 per plate (Fig. 2). On the basis of their morphology, the isolates were initially identified as Sclerotinia sp. (Mordue and Holliday 1976; Kohn 1979). Using the JH1 and JH2 rDNA internal transcribed spacer (ITS) region (GenBank accession no. MZ031405 and MZ031406) and the aspartyl protease gene specific to S. sclerotiorum (MZ292709 and MZ292710) in GenBank as queries, BLAST searches revealed that the sequences were respectively 99%-100% similar to S. sclerotiorum sequences KF859933 and AF271387. The primer pairs for amplifying the ITS region and the aspartyl protease gene were respectively ITS4/ITS5 (White et al. 1990) and SSaspr F/SSaspr R (Abd-Elmagid et al. 2013). The pathogenicity of JH1 and JH2 was evaluated using healthy plants. The roots of 4-year-old ginseng plants were washed, wiped with 75% alcohol, and transferred to flower pots containing sterile sand and sorghum grain (10:1 v/v) infested with 10-day-old isolates. For both isolates, 12 plants were inoculated, with four plants per pot. Control plants were transferred to flower pots containing sorghum grain lacking fungus. The inoculated samples were incubated in a greenhouse (12 h photoperiod and 25 °C) for 25 days before they were examined. The test was repeated twice. The inoculated roots exhibited the same symptoms as those observed in the field, whereas the controls remained symptomless. The same fungus was reisolated from all infected roots and resequencing results confirmed its identity. To the best of our knowledge, this is the first report of S. sclerotiorum causing Sclerotinia root rot on American ginseng in China. Because this disease is detrimental to the production of American ginseng, effective management strategies will need to be developed.

Pathological changes of the perivascular adipose tissue (PVAT) are directly associated with increased risk of age-related vascular diseases. MicroRNAs regulate adipocyte biological functions including adipogenic differentiation and white adipocyte browning. The present study aims to determine whether miR-146b-3p is involved in the regulation of perivascular adipocyte browning during aging. We utilized a cold-induced animal model to investigate the effect of aging on perivascular adipocyte browning. We also detected the miR-146b-3p expression in the PVAT of young or old mice after cold stimulus. We further investigated the role of miR-146b-3p in regulating perivascular adipocyte browning in vitro and in vivo via administrating miRNA mimics or inhibitors. Old mice showed decrease of perivascular adipocyte browning and downregulation of miR-146b-3p expression in the PVAT after cold stimulus. Oil red O staining and qPCR indicated that aging perturbed preadipocyte to brown adipocyte differentiation, and expression of miR-146b-3p gradually increased during differentiation. MiR-146b-3p inhibitors blocked brown adipocyte differentiation in young preadipocytes, whereas miR-146b-3p mimics rescued the differentiation of the old preadipocytes. Finally, miR-146b-3p knocks down inhibited perivascular adipocyte browning in young mice after cold stimulus. Aging inhibits perivascular adipocyte browning, and loss of miR-146b-3p is a potential regulator for this process.

Aims Aging is a risk factor for cardiovascular diseases and adaptive immunity has been implicated in angiotensin (Ang) II-induced target organ dysfunction. Herein, we sought to determine the role of T-cell senescence in Ang II-induced target organ impairment and to explore the underlying mechanisms. Methods and results Flow cytometric analysis revealed that T cell derived from aged mice exhibited immunosenescence. Adoptive transfer of aged T cells to immunodeficient RAG1 KO mice accelerates Ang II-induced cardiovascular and renal fibrosis compared with young T-cell transfer. Aged T cells also promote inflammatory factor expression and superoxide production in these target organs. In vivo and in vitro studies revealed that Ang II promotes interferon-gamma (IFN-γ) production in the aged T cells comparing to young T cells. Importantly, transfer of senescent T cell that IFN-γ KO mitigates the impairment. Aged T-cell-conditioned medium stimulates inflammatory factor expression and oxidative stress in Ang II-treated renal epithelial cells compared with young T cells, and these effects of aged T-cell-conditioned medium are blunted after IFN-γ-neutralizing antibody pre-treatment. Conclusion These results provide a significant insight into the contribution of senescent T cells to Ang II-induced cardiovascular dysfunction and provide an attractive possibility that targeting T cell specifically might be a potential strategy to treat elderly hypertensive patients with end-organ dysfunction.

Aging is an independent risk factor for vascular diseases. Perivascular adipose tissue (PVAT), an active component of the vasculature, contributes to vascular dysfunction during aging. Identification of underlying cell types and their changes during aging may provide meaningful insights regarding the clinical relevance of aging‐related vascular diseases. Here, we take advantage of single‐cell RNA sequence to characterize the resident stromal cells in the PVAT (PVASCs) and identified different clusters between young and aged PVASCs. Bioinformatics analysis revealed decreased endothelial and brown adipogenic differentiation capacities of PVASCs during aging, which contributed to neointimal hyperplasia after perivascular delivery to ligated carotid arteries. Mechanistically, in vitro and in vivo studies both suggested that aging‐induced loss of peroxisome proliferator‐activated receptor‐γ coactivator‐1 α (PGC1α) was a key regulator of decreased brown adipogenic differentiation in senescent PVASCs. We further demonstrated the existence of human PVASCs (hPVASCs) and overexpression of PGC1α improved hPVASC delivery‐induced vascular remodeling. Our finding emphasizes that differentiation capacities of PVASCs alter during aging and loss of PGC1α in aged PVASCs contributes to vascular remodeling via decreased brown adipogenic differentiation.

Iron is abundant in the soil, but its low solubility in neutral or alkaline soils limits its uptake. Plants can rely on rhizosphere acidification to increase iron solubility. OsSEC27p was previously found to be a highly up-regulated gene in iron-deficient rice roots. Here, pH-dependent complementation assays using yeast mutants sec24Δ/SEC24 and sec27Δ/SEC27 showed that OsSEC27 could functionally complement SEC24 but not SEC27 in yeast; thus, it was renamed as OsSEC24. We found that OsSEC24-transgenic tobacco plants increased the length and number of roots under iron deficiency at pH 8.0. To explore how OsSEC24 confers tolerance to iron deficiency, we utilized transgenic tobacco, rice and rice protoplasts. H(+) flux measurements using Non-invasive Micro-test Technology (NMT) indicated that the transgenic OsSEC24 tobacco and rice enhanced H(+) efflux under iron deficiency. Conversely, the application of plasma membrane PM-H(+)-ATPase inhibitor vanadate elucidated that H(+) secretion increased by OsSEC24 was mediated by PM-H(+)-ATPase. OsPMA2 was used as a representative of iron deficiency-responsive PM-H(+)-ATPases in rice root via RT-PCR analysis. In transgenic rice protoplasts OsPMA2 was packaged into OsSEC24 vesicles after export from the ER through confocal-microscopy observation. Together, OsSEC24 vesicles, along with PM-H(+)-ATPases stimulate roots formation under iron deficiency by enhancing rhizosphere acidification.

Adipocytes play important roles in regulating cardiovascular health and disease. However, the molecular mechanism underlying the endocrine role of brown adipose tissue (BAT) in pathological cardiac remodeling remains unknown. Herein we show that adenosine A

Ginseng (Panax ginseng) is a perennial herbaceous plant and a precious traditional Chinese medicine. P. ginseng is widely cultivated in Asia, particularly the Changbai Mountain area in China (Wang et al. 2019). Alternaria species can grow under a wide range of temperatures that occur worldwide (Konstantinova et al. 2002). Alternaria panax was reported as the main cause of Alternaria leaf spot of ginseng (Deng et al. 2013); however, a small-spored Alternaria species was isolated from leaf spot symptoms during recent surveys. In our study, leaf spot disease of P. ginseng was observed during 2017 in the Fusong district, Jilin, China. The disease was widespread, with 20 to 30% of the fields affected. Leaves of the affected plants showed brown to black necrotic spots. The fungus was isolated from symptomatic leaves on potato dextrose agar and characterized morphologically under the microscope. Colonies of pure cultures were initially dark brown and then turned black after 7 days. Strains (TCS 15013001 and TCS 15013002) were grown on water agar embedded with surface-sterilized ginseng spot tissues under a 12/12-h light/dark cycle at room temperature. Conidia observed on the lesions were dark brown or olive-brown, ovoid or ellipsoid, short beaked, with three to seven transverse and zero to five longitudinal septa, and 14.9 to 36.5 μm (average 25.8 μm) × 5.8 to 17.9 μm (average 12.5 μm). Based on its morphological characteristics, the pathogen was identified as Alternaria sp. (Simmons 2007). Single-spore cultures were obtained, and their genomic DNA was extracted. The rDNA internal transcribed spacer (ITS, GenBank accession nos. MN394879 and MN394880), endopolygalacturonase (endoPG, MN410909 and MN410910), Alternaria major allergen (Alta1, MN410911 and MN410912), and the portion of the histone 3 (H3, MN410913 and MN410914), elongation factor 1-alpha (EF1-α, MN410915 and MN410916), the RNA polymerase II 2nd largest subunit (RPB2, MN410917 and MN410918), and glyceraldehyde 3-phosphate dehydrogenase (gpd, MN410919 and MN410920) gene were amplified from the two isolates, respectively (Woudenberg et al. 2015). Sequence analysis of the two isolates showed 99 to 100% identity to that of A. alternata (MG182428 for ITS, MG598798 for endoPG, MG598796 for Alt a1, MG182429 for H3, KU738723 for EF1-α, KU738707 for RPB2, and KP851761 for gpd). Pathogenicity tests were conducted in a greenhouse. Sixty healthy 2-year-old P. ginseng seedlings grown in potting medium were tested in a greenhouse at 20/26°C and about 90% relative humidity with natural light. Of the plants, 30 were sprayed with spore suspension (1 × 10⁵ spores/ml) until most of the leaves were wet. Control treatments (30 plants) were treated with distilled water. The two isolates were tested, and all test plants were covered with clear plastic bags for 3 days to increase humidity. Each treatment had three replicate plants. Six days after inoculation, leaf spots similar to the original ones developed at inoculation sites for all isolates, and A. alternata was consistently reisolated from the induced symptoms. The pathogenicity test was performed three times. A. alternata causing leaf spot of American ginseng was reported in China (Hill and Hausbeck 2008). Also, leaf spot of Panax notoginseng caused by A. alternata was reported in China (Yang et al. 2018). To our knowledge, this is the first report of A. alternata on P. ginseng in China.

Iron (Fe)-homeostasis in the plastids is closely associated with Fe transport proteins that prevent Fe from occurring in its toxic free ionic forms. However, the number of known protein families related to Fe transport in the plastids (about five) and the function of iron in non-green plastids is limited. In the present study, we report the functional characterization of Zea mays Fe deficiency-related 4 (ZmFDR4), which was isolated from a differentially expressed clone of a cDNA library of Fe deficiency-induced maize roots. ZmFDR4 is homologous to the bacterial FliP superfamily, coexisted in both algae and terrestrial plants, and capable of restoring the normal growth of the yeast mutant fet3fet4, which possesses defective Fe uptake systems. ZmFDR4 mRNA is ubiquitous in maize and is inducible by iron deficiency in wheat. Transient expression of the 35S:ZmFDR4-eGFP fusion protein in rice protoplasts indicated that ZmFDR4 maybe localizes to the plastids envelope and thylakoid. In 35S:c-Myc-ZmFDR4 transgenic tobacco, immunohistochemistry and immunoblotting confirmed that ZmFDR4 is targeted to both the chloroplast envelope and thylakoid. Meanwhile, ultrastructure analysis indicates that ZmFDR4 promotes the density of plastids and accumulation of starch grains. Moreover, Bathophenanthroline disulfonate (BPDS) colorimetry and inductively coupled plasma mass spectrometry (ICP-MS) indicate that ZmFDR4 is related to Fe uptake by plastids and increases seed Fe content. Finally, 35S:c-Myc-ZmFDR4 transgenic tobacco show enhanced photosynthetic efficiency. Therefore, the results of the present study demonstrate that ZmFDR4 functions as an iron transporter in monocot plastids and provide insight into the process of Fe uptake by plastids.

The COP9 signalosome (CSN) plays an important role in proteasome-mediated degradation by regulating CUL1 rubylation of the SCF ligase and is involved in many crucial biological processes. Here, we demonstrate a link between IDEF1 accumulation and the decline in COP9 derubylation activity in response to iron deficiency (-Fe) in rice (Oryza sativa). CSN6 expression is rapidly down-regulated during Fe depletion, contributing to reduced CSN activity, as judged by CSN5 and CUL1 expression, indicating CSN6 is involved in the early stage response of -Fe. In contrast to CSN6, the IDEF1 protein and expression of several iron uptake/utilisation-related genes are increased in response to -Fe. Thus, we constructed CSN6 transgenic sense and antisense lines and found that experimental depletion of CSN6 results in accumulation of the IDEF1 protein and up-regulation of several iron uptake/utilisation-related genes. Furthermore, IDEF1 can be decorated with K48-linked polyubiquitin and degraded via the 26S proteasome. Accumulated IDEF1 in antisense lines led to increased chlorophyll and Fe content in seedlings during -Fe. Collectively, the cellular CSN6 level is decreased during early stages of -Fe to ensure the rapid accumulation of IDEF1, which in turn up-regulates several iron uptake/utilisation-related genes to help overcome -Fe stress in rice.