Objective: To investigate the clinicopathological features and differential diagnosis of eosinophilic vacuolated tumor (EVT). Methods: Seven cases of EVT with characteristic morphology and unequivocal diagnosis from the Affiliated Hospital of Qingdao University (6 cases), Qingdao, China and the 971 Hospital of PLA Navy (1 case), Qingdao, China between January 2010 and December 2021 were subject to morphological and immunohistochemical analyses. Additionally, whole exome sequencing (WES) was performed in two cases. Twenty-two cases of renal oncocytoma (RO) and 17 cases of eosinophilic chromophobe renal cell carcinoma (eChRCC) diagnosed at the same time were used as controls. Results: Four males and three females with a mean age of 42 years (range: 29-61 years) were included in the study. The tumors were nodular and well-circumscribed, with sizes ranging from 1.5 to 4.5 cm. On cross-section, they appeared gray-red or gray-white, solid, and soft. Tumor cells were arranged in nests, solid sheets, and acinar or small vesicular structures. These cells exhibited eosinophilic cytoplasm with large, prominent clear vacuoles and round nuclei with prominent nucleoli. Perinuclear halos were focally present in four cases, while small tumor cells with sparse cytoplasm and hyperchromatic nuclei were seen in one case. No necrosis or mitosis was noted. Edematous stroma was detected in three cases. All tumors were positive for CD117 and Cathepsin K, but negative for vimentin and CK7. CK20 was positive in scattered individual cells, and Ki-67 positivity ranged from 1% to 4%. Point mutations in MTOR were identified in both patients who were subject to the molecular analysis. Statistical differences in the expression of Cathepsin K, CD10, S-100A1, and Cyclin D1 between EVT and RO (P<0.05) were significant, so were the differences in the expression of Cathepsin K, CD10, CK7 and claudin 7 between EVT and eChRCC (P<0.001). Seven patients were followed up for 4 to 96 months (mean, 50 months), with no recurrences or metastases. Conclusions: EVT is a rare renal tumor that shares morphological and immunophenotypic features with RO and eChRCC, and it is closely linked to the TSC/MTOR pathway. The presence of large prominent transparent vacuoles in eosinophilic cytoplasm along with conspicuous nucleoli is its key morphological characteristics. The use of combined immunohistochemical stains greatly aids in its diagnosis. Typically, the tumor exhibits indolent biological behaviors with a favorable prognosis.
目的： 探讨肾嗜酸性空泡状肿瘤（eosinophilic vacuolated tumor，EVT）的临床病理学特点及诊断、鉴别诊断。 方法： 收集2010年1月至2021年12月青岛大学附属医院（6例）和海军第九七一医院（1例）形态学典型、病理诊断无异议的肾EVT，进行组织形态学观察、免疫组织化学染色，并对2例进行全外显子测序。另选取同期诊断的肾嗜酸细胞瘤（RO）22例、嗜酸型嫌色细胞肾细胞癌（eChRCC）17例进行比较。 结果： 男性4例，女性3例。年龄29~61岁（平均年龄42岁）。临床上，7例均系体检发现，瘤体直径1.5~4.5 cm，结节状，边界清楚，切面灰红、灰白色，实性，质软。镜下观察：瘤组织呈巢团状或实性排列，伴有多少不等的腺泡状或小囊状结构，瘤细胞胞质嗜酸，胞质内均可见大而突出的透明空泡，核圆形，核仁明显，4例局部可见核周空晕，1例见灶状分布、胞质稀少、核深染的小细胞成分。所有病例均未见坏死和核分裂象。3例存在水肿性间质。免疫组织化学染色：7例肿瘤均呈CD117、Cathepsin K阳性，波形蛋白、细胞角蛋白（CK）7阴性，CK20散在或斑片状阳性，Ki-67阳性指数1%~4%。全外显子测序显示2例肿瘤均存在MTOR基因突变。统计学分析表明，EVT与RO中Cathepsin K、CD10、S-100A1和Cyclin D1的表达（P<0.05）及EVT与eChRCC中Cathepsin K、CD10、CK7和claudin7的表达（P<0.001）差异有统计学意义。7例随访4~96个月（平均50个月），均未见复发或转移。 结论： 肾EVT是一种在形态学、免疫表型与RO、eChRCC均有重叠、与TSC/MTOR通路密切相关的少见肾肿瘤，嗜酸性胞质内可见大而突出的透明空泡以及存在显著的核仁是该肿瘤的重要组织学特征。联合应用系列免疫组织化学抗体有助于EVT的诊断与鉴别诊断。该肿瘤生物学行为通常惰性，预后良好。.

The Legionella pneumophila Sde family of translocated proteins promotes host tubular endoplasmic reticulum (ER) rearrangements that are tightly linked to phosphoribosyl-ubiquitin (pR-Ub) modification of Reticulon 4 (Rtn4). Sde proteins have two additional activities of unclear relevance to the infection process: K63 linkage-specific deubiquitination and phosphoribosyl modification of polyubiquitin (pR-Ub). We show here that the deubiquitination activity (DUB) stimulates ER rearrangements while pR-Ub protects the replication vacuole from cytosolic surveillance by autophagy. Loss of DUB activity is tightly linked to lowered pR-Ub modification of Rtn4, consistent with the DUB activity fueling the production of pR-Ub-Rtn4. In parallel, phosphoribosyl modification of polyUb, in a region of the protein known as the isoleucine patch, prevents binding by the autophagy adapter p62. An inability of Sde mutants to modify polyUb results in immediate p62 association, a critical precursor to autophagic attack. The ability of Sde WT to block p62 association decays quickly after bacterial infection, as predicted by the presence of previously characterized L. pneumophila effectors that inactivate Sde and remove polyUb. In sum, these results show that the accessory Sde activities act to stimulate ER rearrangements and protect from host innate immune sensing in a temporal fashion.

Plants have developed precise defense mechanisms against cadmium (Cd) stress, with vacuolar compartmentalization of Cd2+ being a crucial process in Cd detoxification. The transport of Cd into vacuoles by these cation / H+ antiporters is powered by the pH gradient created by proton pumps. In this study, the full-length cDNA of a vacuolar H+-pyrophosphatase (V-PPase) gene from Boehmeria nivea (ramie), BnVP1, was isolated using the rapid amplification of cDNA ends (RACE) method. The open reading frame (ORF) of BnVP1 is 2292 bp, encoding a 763 amino acid V-PPase protein with 15 predicted transmembrane domains. Sequence alignment and phylogenetic analysis revealed that BnVP1 belongs to the Type I V-PPase family. Quantitative RT-PCR assays demonstrated that BnVP1 expression was significantly higher in ramie roots than in shoots. Cd treatments markedly induced BnVP1 expression in both roots and leaves of ramie seedlings, with a more pronounced effect in roots. Additionally, BnVP1 expression was significantly upregulated by the plant hormone methyl jasmonate (MeJA). Heterologous expression of BnVP1 in transgenic Arabidopsis significantly enhanced V-PPase activity in the roots. The growth performance, root elongation, and total chlorophyll content of transgenic plants with high tonoplast H+-PPase (V-PPase) activity were superior to those of wild-type plants. Overexpression of BnVP1 reduced membrane lipid peroxidation and ion leakage, and significantly increased Cd accumulation in the roots of transgenic Arabidopsis seedlings. This study provides new genetic resources for the phytoremediation of Cd-contaminated farmland.

The pistil is the most important organ for fertilization in flowering plants, and the stigmatic papilla cells are responsible for pollen acceptance and pollen tube germination. Arabidopsis plants possess dry stigmas exhibiting high selectivity for compatible pollen. When compatible pollens are recognized and accepted by stigmatic papilla cells, water and nutrients are then transported from the stigma to pollen grains through the secretory pathway. Here, we present light microscopy-based methods for investigating autophagy and senescence of stigmatic papilla cells. These methods include the assessment of viability of stigmatic papilla cells using dual staining with fluorescein diacetate/propidium iodide, as well as the examination of vacuolar-accumulated proteins during stigma senescence. These methods can be used to understand the functions of the stigma tissue from a subcellular perspective.

Vacuoles in plant cells are the most prominent organelles that harbor distinctive features, including lytic function, storage of proteins and sugars, balance of cell volume, and defense responses. Despite their dominant size and functional versatility, the nature and biogenesis of vacuoles in plants per se remain elusive and several models have been proposed. Recently, we used the whole-cell 3D electron tomography (ET) technique to study vacuole formation and distribution at nanometer resolution and demonstrated that small vacuoles are derived from multivesicular body maturation and fusion. Good sample preparation is a critical step to get high-quality electron tomography images. In this chapter, we provide detailed sample preparation methods for high-resolution ET in Arabidopsis thaliana root cells, including high-pressure freezing, subsequent freeze-substitution fixation, embedding, and serial sectioning.

Arabidopsis thaliana developing pollen grains serve as an excellent system for studying vacuole dynamics. Here, we present a methodological approach that utilizes the serial tomography package in Etomo software from IMOD to generate whole-cell tomograms on A. thaliana developing pollens for visualizing vacuoles on the whole-cell scale. In order to understand the vacuole dynamics along with the pollen maturation, we also introduce a sampling method aimed at harvesting the pollen grains at various stages, marked by the vegetative nucleus or generative cell. The cryo-fixation/freeze-substitution technique can then be applied to preserve the fine structures of the pollen grains and facilitate detailed ultrastructure examination. Through this method, large-volume whole-cell electron tomograms regarding vacuolar morphologies and ultrastructural changes during pollen development and maturation have been obtained. Overall, the method presented here provides valuable insights into the dynamic nature of vacuoles in Arabidopsis developing pollen.

Protein secretion and vacuole formation are vital processes in plant cells, playing crucial roles in various aspects of plant development, growth, and stress responses. Multiple regulators have been uncovered to be involved in these processes. In animal cells, the transcription factor TFEB has been extensively studied and its role in lysosomal biogenesis is well understood. However, the transcription factors governing protein secretion and vacuole formation in plants remain largely unexplored. In recent years, an increasing number of bioinformatics databases and tools have been developed, facilitating computational prediction and analysis of the function of genes or proteins in specific cellular processes. Leveraging these resources, this chapter aims to provide practical guidance on how to effectively utilize these existing databases and tools for the analysis of key transcription factors involved in regulating protein secretion and vacuole formation in plants, with a particular focus on Arabidopsis and other higher plants. The findings from this analysis can serve as a valuable resource for future experimental investigations and the development of targeted strategies to manipulate protein secretion and vacuole formation in plants.

Plant vacuoles, play a crucial role in maintaining cellular stability, adapting to environmental changes, and responding to external pressures. The accurate identification of vacuolar proteins (PVPs) is crucial for understanding the biosynthetic mechanisms of intracellular vacuoles and the adaptive mechanisms of plants. In order to more accurately identify vacuole proteins, this study developed a new predictive model PEL-PVP based on ESM-2. Through this study, the feasibility and effectiveness of using advanced pre-training models and fine-tuning techniques for bioinformatics tasks were demonstrated, providing new methods and ideas for plant vacuolar protein research. In addition, previous datasets for vacuolar proteins were balanced, but imbalance is more closely related to the actual situation. Therefore, this study constructed an imbalanced dataset UB-PVP from the UniProt database，helping the model better adapt to the complexity and uncertainty in real environments, thereby improving the model\'s generalization ability and practicality. The experimental results show that compared with existing recognition techniques, achieving significant improvements in multiple indicators, with 6.08 %, 13.51 %, 11.9 %, and 5 % improvements in ACC, SP, MCC, and AUC, respectively. The accuracy reaches 94.59 %, significantly higher than the previous best model GraphIdn. This provides an efficient and precise tool for the study of plant vacuole proteins.

Autophagy is essential for maintaining glucose homeostasis. However, the mechanism by which cells sense and respond to glucose starvation to induce autophagy remains incomplete. Here, we show that calcium serves as a fundamental triggering signal that connects environmental sensing to the formation of the autophagy initiation complex during glucose starvation. Mechanistically, glucose starvation instigates the release of vacuolar calcium into the cytoplasm, thus triggering the activation of Rck2 kinase. In turn, Rck2-mediated Atg11 phosphorylation enhances Atg11 interactions with Bmh1/2 bound to the Snf1-Sip1-Snf4 complex, leading to recruitment of vacuolar membrane-localized Snf1 to the PAS and subsequent Atg1 activation, thereby initiating autophagy. We also identified Glc7, a protein phosphatase-1, as a critical regulator of the association between Bmh1/2 and the Snf1 complex. We thus propose that calcium-triggered Atg11-Bmh1/2-Snf1 complex assembly initiates autophagy by controlling Snf1-mediated Atg1 activation in response to glucose starvation.

Stomata play a crucial role in plants by controlling water status and responding to drought stress. However, simultaneously improving stomatal opening and drought tolerance has proven to be a significant challenge. To address this issue, we employed the OnGuard quantitative model, which accurately represents the mechanics and coordination of ion transporters in guard cells. With the guidance of OnGuard, we successfully engineered plants that overexpressed the main tonoplast Ca2+-ATPase gene, ACA11, which promotes stomatal opening and enhances plant growth. Surprisingly, these transgenic plants also exhibited improved drought tolerance due to reduced water loss through their stomata. Again, OnGuard assisted us in understanding the mechanism behind the unexpected stomatal behaviors observed in the ACA11 overexpressing plants. Our study revealed that the overexpression of ACA11 facilitated the accumulation of Ca2+ in the vacuole, thereby influencing Ca2+ storage and leading to an enhanced Ca2+ elevation in response to abscisic acid. This regulatory cascade finely tunes stomatal responses, ultimately leading to enhanced drought tolerance. Our findings underscore the importance of tonoplast Ca2+-ATPase in manipulating stomatal behavior and improving drought tolerance. Furthermore, these results highlight the diverse functions of tonoplast-localized ACA11 in response to different conditions, emphasizing its potential for future applications in plant enhancement.