OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with Hereditary spastic paraplegia type 3A (SPG3A) and the genotype-phenotype correlation. METHODS: A three-generation pedigree presented at Huantai Maternal and Child Health Care Hospital in March 2021 was selected as the study subject. Whole-exome sequencing (WES) and pedigree analysis was carried out. Candidate variant was validated by Sanger sequencing of the members from the pedigree. Haplotype analysis was used to trace the origin of the variant, and pathogenicity was rated based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: 2025-12). RESULTS: A c.1024C>T (p.Pro342Ser) variant of the ATL1 was identified in the four affected members, including the proband, but none of the three unaffected relatives. Haplotype analysis suggested that the variant was derived from the proband's mother and has co-segregated with the disease phenotype. Based on the guidelines of the ACMG, it was classified as likely pathogenic. CONCLUSION The ATL1 c.1024C>T (p.Pro342Ser) variant probably underlay the pathogenesis in this pedigree. Above finding has enriched the mutational spectrum of ATL1 and phenotypic spectrum of SPG3A in the Chinese population, and enabled genetic counseling for this pedigree.
Humans ; Pedigree ; Spastic Paraplegia, Hereditary/genetics* ; Male ; Female ; Asian People/genetics* ; Adult ; Haplotypes ; Membrane Proteins/genetics* ; Exome Sequencing ; GTP-Binding Proteins/genetics* ; Mutation ; Middle Aged ; China ; Genetic Association Studies ; East Asian People

OBJECTIVE: To explore the improvement effect of electroacupuncture (EA) based on <i>Xingnao Kaiqiaoi> acupuncture (acupuncture for regaining consciousness and opening orifices) on cognitive impairment in mice with Parkinson's disease (PD), and to explore its regulatory mechanisms on the kinesin family member 5A (KIF5A)/mitochondrial Rho GTPase 1 (Miro1) pathway and mitophagy in prefrontal cortical neurons. METHODS: A total of 70 male C57BL/6J mice of clean grade were randomly divided into a normal group (12 mice), a sham operation group (12 mice), and a model pre-screening group (46 mice). Unilateral stereotaxic injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle was adopted to establish the PD model in the model pre-screening group. Twenty-four mice after successful modeling were randomly selected and divided into a model group and an EA group, 12 mice in each one. In the EA group, acupuncture was applied at "Shuigou" (GV26) and bilateral "Sanyinjiao" (SP6) and "Neiguan" (PC6), ipsilateral "Sanyinjiao" (SP6) and "Neiguan" (PC6) were connected to EA respectively, with disperse-dense wave, 5 Hz/20 Hz in frequency, 0.5 mA in current intensity, 20 min a time, 6 times a week for 30 days. Cognitive function was assessed by Y-maze and Morris water maze tests; morphology of prefrontal cortex was observed by H.E. staining; reactive oxygen species (ROS) level in prefrontal cortex was detected by fluorescence probe method; mitochondrial morphology and autophagosome ultrastructure were observed by transmission electron microscopy; the mRNA expression of tyrosine hydroxylase (TH) was detected by quantitative real-time PCR; the protein expression of TH, KIF5A, Miro1, p62, Parkin and PTEN induced kinase 1 (PINK1) was detected by Western blot. RESULTS: Compared with the sham operation group, both the model group and the EA group exhibited increased rotation number of per minute (<i>Pi><0.001). Compared with the sham operation group, in the model group, the novel arm exploration time of Y-maze test was shortened (<i>Pi><0.001), the escape latency of Morris water maze test was prolonged (<i>Pi><0.05) and the platform crossing number of Morris water maze test was reduced (<i>Pi><0.01); in the prefrontal cortex, the number of cellular vacuole and neurons with karyopyknosis was increased (<i>Pi><0.001), and mitochondrial autophagosomes could be observed; in the prefrontal cortex, the relative expression of ROS was increased (<i>Pi><0.001), the protein and mRNA expression of TH was decreased (<i>Pi><0.001), the protein expression of Miro1, PINK1, Parkin was increased (<i>Pi><0.001, <i>Pi><0.01), the protein expression of KIF5A and p62 was decreased (<i>Pi><0.001). Compared with the model group, in the EA group, the novel arm exploration time of Y-maze test was prolonged (<i>Pi><0.01), the escape latency of Morris water maze test was shortened (<i>Pi><0.05) and the platform crossing number of Morris water maze test was increased (<i>Pi><0.05); in the prefrontal cortex, the number of cellular vacuole and neurons with karyopyknosis was decreased (<i>Pi><0.001), and the number of mitochondrial autophagosomes reduced and the mitochondrial morphology was improved; in the prefrontal cortex, the relative expression of ROS was decreased (<i>Pi><0.01), the protein and mRNA expression of TH was increased (<i>Pi><0.001, <i>Pi><0.01), the protein expression of Miro1, PINK1, Parkin was decreased (<i>Pi><0.001, <i>Pi><0.01, <i>Pi><0.05), the protein expression of KIF5A and p62 was increased (<i>Pi><0.01, <i>Pi><0.05). CONCLUSION <i>Xingnao Kaiqiaoi> electroacupuncture effectively alleviates cognitive impairment and damage of neuronal function in PD mice, its mechanism may be related to the regulation of KIF5A/Miro1 pathway, hence reducing the mitophagy in prefrontal cortical neurons.
Animals ; Electroacupuncture ; Male ; Mice ; Parkinson Disease/physiopathology* ; Cognitive Dysfunction/psychology* ; Kinesins/genetics* ; Humans ; Mitophagy ; Mice, Inbred C57BL ; rho GTP-Binding Proteins/genetics* ; Mitochondria/genetics* ; Prefrontal Cortex/metabolism*

Endosomes are characterized by the presence of various phosphoinositides that are essential for defining the membrane properties. However, the interplay between endosomal phosphoinositides metabolism and innate immunity is yet to be fully understood. Here, our findings highlight the evolutionary continuity of RAB-10/Rab10's involvement in regulating innate immunity. Upon infection of Caenorhabditis elegans with Pseudomonas aeruginosa, an increase in RAB-10 activity was observed in the intestine. Conversely, when RAB-10 was absent, the intestinal diacylglycerols (DAGs) decreased, and the animal's response to the pathogen was impaired. Further research revealed that UNC-16/JIP3 acts as an RAB-10 effector, facilitating the recruitment of phospholipase EGL-8 to endosomes. This leads to a decrease in endosomal phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and an elevation of DAGs, as well as the activation of the PMK-1/p38 MAPK innate immune pathway. It is noteworthy that the dimerization of UNC-16 is a prerequisite for its interaction with RAB-10(GTP) and the recruitment of EGL-8. Moreover, we ascertained that the rise in RAB-10 activity, due to infection, was attributed to the augmented expression of LET-413/Erbin, and the nuclear receptor NHR-25/NR5A1/2 was determined to be indispensable for this increase. Hence, this study illuminates the significance of endosomal PI(4,5)P2 catabolism in boosting innate immunity and outlines an NHR-25-mediated mechanism for pathogen detection in intestinal epithelia.
Animals ; Caenorhabditis elegans/genetics* ; Endosomes/immunology* ; Caenorhabditis elegans Proteins/immunology* ; Phosphatidylinositol 4,5-Diphosphate/immunology* ; Immunity, Innate ; Pseudomonas aeruginosa/immunology* ; rab GTP-Binding Proteins/genetics* ; Diglycerides/metabolism*

SMARCA4-deficient non small cell lung cancer (SMARCA4-dNSCLC) has recently garnered increasing attention due to its high malignancy and poor prognosis. The literature suggests that in non small cell lung cancer (NSCLC), the loss of SMARCA4 frequently co-occurs with mutations in KRAS, KEAP1, and STK11 rather than in EGFR, ALK, and ROS1. Herein, we present the first documented case of SMARCA4-dNSCLC accompanied with rare mutations of EGFR exon 20 S768I and exon 18 G719X. The patient achieved partial response with afatinib for 17 months. Our case highlights the importance of EGFR mutations in the precision targeted treatment of SMARCA4-dNSCLC.
Humans ; Afatinib/therapeutic use* ; Antineoplastic Agents/therapeutic use* ; Carcinoma, Non-Small-Cell Lung/pathology* ; DNA Helicases/genetics* ; ErbB Receptors/genetics* ; Lung Neoplasms/pathology* ; Mutation ; Nuclear Proteins/genetics* ; Transcription Factors/genetics*

Patients with severe pneumonia caused by novel coronavirus infection are often complicated with acute respiratory distress syndrome (ARDS), which has a high mortality. ARDS is characterized by diffuse alveolar damage, pulmonary edema, and hypoxemia. Mitochondria are prone to morphological and functional abnormalities under hypoxia and viral infection, which can lead to cell apoptosis and damage, severely impacting the disease progression. Mitochondria maintain homeostasis through fission and fusion. In ARDS, hypoxia leads to the phosphorylation of dynamin-related protein 1 (Drp1), triggering excessive mitochondrial fission and damaging the alveolar epithelial barrier. Animal experiments have shown that inhibiting this process can alleviate lung injury, providing a potential direction for treatment. The pathology of novel coronavirus infection-related ARDS is similar to that of typical ARDS but more severe. Viral infection and hypoxia disrupt the mitochondrial balance, causing fission and autophagy abnormalities, promoting oxidative stress and mitochondrial DNA (mtDNA) release, activating inflammasomes, inducing the expression of hypoxia-inducible factor-1α (HIF-1α), exacerbating viral infection, inflammation, and coagulation reactions, and resulting in multiple organ damage. Mechanical ventilation and glucocorticoids are commonly used in the treatment of novel coronavirus infection-related ARDS. Mechanical ventilation is likely to cause lung and diaphragm injuries and changes in mitochondrial dynamics, while the lung protective ventilation strategy can reduce the adverse effects. Glucocorticoids can regulate mitochondrial function and immune response and improve the patient's condition through multiple pathways. The mitochondrial dynamics imbalance in novel coronavirus infection-related ARDS is caused by hypoxia and viral proteins, leading to lung and multiple organ injuries. To clarify the pathophysiological mechanism of mitochondrial dynamics imbalance in novel coronavirus infection-related ARDS and explore effective strategies for regulating mitochondrial dynamics balance to treat this disease, so as to provide new treatment targets and methods for patients with novel coronavirus infection-related ARDS. The existing treatments have limitations. Future research needs to deeply study the mechanism of mitochondrial dysfunction, develop new therapies and regulatory strategies, and improve the treatment effect.
Humans ; Respiratory Distress Syndrome/etiology* ; COVID-19 ; Mitochondrial Dynamics ; Mitochondria/metabolism* ; DNA, Mitochondrial ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Dynamins ; SARS-CoV-2

This study aims to investigate the molecular mechanism by which naringin alleviates cerebral ischemia/reperfusion(CI/R) injury through DRP1/LRRK2/MCU signaling axis. A total of 60 SD rats were randomly divided into the sham group, the model group, the sodium Danshensu group, and low-, medium-, and high-dose(50, 100, and 200 mg·kg~(-1)) naringin groups, with 10 rats in each group. Except for the sham group, a transient middle cerebral artery occlusion/reperfusion(tMCAO/R) model was established in SD rats using the suture method. Longa 5-point scale was used to assess neurological deficits. 2,3,5-Triphenyl tetrazolium chloride(TTC) staining was used to detect the volume percentage of cerebral infarction in rats. Hematoxylin-eosin(HE) staining and Nissl staining were employed to assess neuronal structural alterations and the number of Nissl bodies in cortex, respectively. Western blot was used to determine the protein expression levels of B-cell lymphoma-2 gene(Bcl-2), Bcl-2-associated X protein(Bax), cleaved cysteine-aspartate protease-3(cleaved caspase-3), mitochondrial calcium uniporter(MCU), microtubule-associated protein 1 light chain 3(LC3), and P62. Mitochondrial structure and autophagy in cortical neurons were observed by transmission electron microscopy. Immunofluorescence assay was used to quantify the fluorescence intensities of MCU and mitochondrial calcium ion, as well as the co-localization of dynamin-related protein 1(DRP1) with leucine-rich repeat kinase 2(LRRK2) and translocase of outer mitochondrial membrane 20(TOMM20) with LC3 in cortical mitochondria. The results showed that compared with the model group, naringin significantly decreased the volume percentage of cerebral infarction and neurological deficit score in tMCAO/R rats, alleviated the structural damage and Nissl body loss of cortical neurons in tMCAO/R rats, inhibited autophagosomes in cortical neurons, and increased the average diameter of cortical mitochondria. The Western blot results showed that compared to the sham group, the model group exhibited increased levels of cleaved caspase-3, Bax, MCU, and the LC3Ⅱ/LC3Ⅰ ratio in the cortex and reduced protein levels of Bcl-2 and P62. However, naringin down-regulated the protein expression of cleaved caspase-3, Bax, MCU and the ratio of LC3Ⅱ/LC3Ⅰ ratio and up-regulated the expression of Bcl-2 and P62 proteins in cortical area. In addition, immunofluorescence analysis showed that compared with the model group, naringin and positive drug treatments significantly decreased the fluorescence intensities of MCU and mitochondrial calcium ion. Meanwhile, the co-localization of DRP1 with LRRK2 and TOMM20 with LC3 in cortical mitochondria was also decreased significantly after the intervention. These findings suggest that naringin can alleviate cortical neuronal damage in tMCAO/R rats by inhibiting DRP1/LRRK2/MCU-mediated mitochondrial fragmentation and the resultant excessive mitophagy.
Animals ; Rats, Sprague-Dawley ; Reperfusion Injury/genetics* ; Flavanones/administration & dosage* ; Rats ; Dynamins/genetics* ; Male ; Brain Ischemia/genetics* ; Protein Serine-Threonine Kinases/genetics* ; Signal Transduction/drug effects* ; Humans ; Drugs, Chinese Herbal/administration & dosage*

This study investigated the effects and underlying mechanisms of vanillic acid(VA) against cardiac fibrosis(CF) induced by isoproterenol(ISO) in mice. Male C57BL/6J mice were randomly divided into control group, VA group(100 mg·kg~(-1), ig), ISO group(10 mg·kg~(-1), sc), ISO + VA group(10 mg·kg~(-1), sc + 100 mg·kg~(-1), ig), ISO + dynamin-related protein 1(Drp1) inhibitor(Mdivi-1) group(10 mg·kg~(-1), sc + 50 mg·kg~(-1), ip), and ISO + VA + Mdivi-1 group(10 mg·kg~(-1), sc + 100 mg·kg~(-1), ig + 50 mg·kg~(-1), ip). The treatment groups received the corresponding medications once daily for 14 consecutive days. On the day after the last administration, cardiac functions were evaluated, and serum and cardiac tissue samples were collected. These samples were analyzed for serum aspartate aminotransferase(AST), lactate dehydrogenase(LDH), creatine kinase-MB(CK-MB), cardiac troponin I(cTnI), reactive oxygen species(ROS), interleukin(IL)-1β, IL-4, IL-6, IL-10, IL-18, and tumor necrosis factor-α(TNF-α) levels, as well as cardiac tissue catalase(CAT), glutathione(GSH), malondialdehyde(MDA), myeloperoxidase(MPO), superoxide dismutase(SOD), total antioxidant capacity(T-AOC) activities, and cytochrome C levels in mitochondria and cytoplasm. Hematoxylin-eosin, Masson, uranium acetate and lead citrate staining were used to observe morphological and mitochondrial ultrastructural changes in the cardiac tissues, and myocardial injury area and collagen volume fraction were calculated. Flow cytometry was applied to detect the relative content and M1/M2 polarization of cardiac macrophages. The mRNA expression levels of macrophage polarization markers [CD86, CD206, arginase 1(Arg-1), inducible nitric oxide synthase(iNOS)], CF markers [type Ⅰ collagen(Coll Ⅰ), Coll Ⅲ, α-smooth muscle actin(α-SMA)], and cytokines(IL-1β, IL-4, IL-6, IL-10, IL-18, TNF-α) in cardiac tissues were determined by quantitative real-time PCR. Western blot was used to detect the protein expression levels of Coll Ⅰ, Coll Ⅲ, α-SMA, Drp1, p-Drp1, voltage-dependent anion channel(VDAC), hexokinase 1(HK1), NOD-like receptor protein 3(NLRP3), apoptosis-associated speck-like protein(ASC), caspase-1, cleaved-caspase-1, gasdermin D(GSDMD), cleaved N-terminal gasdermin D(GSDMD-N), IL-1β, IL-18, B-cell lymphoma-2(Bcl-2), B-cell lymphoma-xl(Bcl-xl), Bcl-2-associated death promoter(Bad), Bcl-2-associated X protein(Bax), apoptotic protease activating factor-1(Apaf-1), pro-caspase-3, cleaved-caspase-3, pro-caspase-9, cleaved-caspase-9, poly(ADP-ribose) polymerase-1(PARP-1), and cleaved-PARP-1 in cardiac tissues. The results showed that VA significantly improved cardiac function in mice with CF, reduced myocardial injury area and cardiac index, and decreased serum levels of AST, CK-MB, cTnI, LDH, ROS, IL-1β, IL-6, IL-18, and TNF-α. VA also lowered MDA and MPO levels, mRNA expressions of IL-1β, IL-6, IL-18, and TNF-α, and mRNA and protein expressions of Coll Ⅰ, Coll Ⅲ, and α-SMA in cardiac tissues, and increased serum levels of IL-4 and IL-10, cardiac tissue levels of CAT, GSH, SOD, and T-AOC, and mRNA expressions of IL-4 and IL-10. Additionally, VA ameliorated cardiac pathological damage, inhibited myocardial cell apoptosis, inflammatory infiltration, and collagen fiber deposition, reduced collagen volume fraction, and alleviated mitochondrial damage. VA decreased the ratio of F4/80~+CD86~+ M1 cells and the mRNA expressions of CD86 and iNOS in cardiac tissue, and increased the ratio of F4/80~+CD206~+ M2 cells and the mRNA expressions of CD206 and Arg-1. VA also reduced protein expressions of p-Drp1, VDAC, NLRP3, ASC, caspase-1, cleaved-caspase-1, GSDMD, GSDMD-N, IL-1β, IL-18, Bad, Bax, Apaf-1, cleaved-caspase-3, cleaved-caspase-9, cleaved-PARP-1, and cytoplasmic cytochrome C, and increased the expressions of HK1, Bcl-2, Bcl-xl, pro-caspase-3, pro-caspase-9 proteins, as well as the Bcl-2/Bax and Bcl-xl/Bad ratios and mitochondrial cytochrome C content. These results indicate that VA has a significant ameliorative effect on ISO-induced CF in mice, alleviates ISO-induced oxidative damage and inflammatory response, and its mechanism may be closely related to the inhibition of Drp1/HK1/NLRP3 and mitochondrial apoptosis signaling pathways, suppression of myocardial cell inflammatory infiltration and collagen fiber deposition, reduction of collagen volume fraction and CollⅠ, Coll Ⅲ, and α-SMA expressions, thus mitigating CF.
Animals ; Isoproterenol/adverse effects* ; Male ; Mice ; Signal Transduction/drug effects* ; Vanillic Acid/administration & dosage* ; Dynamins/genetics* ; Mice, Inbred C57BL ; Fibrosis/genetics* ; Apoptosis/drug effects* ; Mitochondria/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Myocardium/metabolism* ; Humans

Cardiovascular diseases are the leading cause of mortality, posing a significant threat to human health due to the high incidence rate. Atherosclerosis, a chronic inflammatory disease, serves as the primary pathological basis for most such conditions. The incidence of atherosclerosis continues to rise, but its pathogenesis has not been fully elucidated. As an important member of the small GTPase superfamily, Ras-association proximate 1 (Rap1) is an important molecular switch involved in the regulation of multiple physiological functions including cell differentiation, proliferation, and adhesion. Rap1 achieves the utility of the molecular switch by cycling between Rap1-GTP and Rap1-GDP. Rap1 may influence the occurrence and development of atherosclerosis in a cell-specific manner. This article summarizes the potential role and mechanism of Rap1 in the progression of atherosclerosis in different cells, aiming to provide new therapeutic targets and strategies for clinical intervention.
Humans ; Atherosclerosis/metabolism* ; rap1 GTP-Binding Proteins/physiology* ; Animals ; Cell Differentiation ; Cell Adhesion ; Cell Proliferation

Soil cadmium (Cd) pollution is one of the major environmental problems globally. <i>Ophiopogon japonicusi>, a multifunctional plant extensively used in traditional Chinese medicine, has demonstrated potential in environmental remediation. This study investigated the Cd accumulation pattern of <i>Oi>. <i>japonicusi> under cadmium stress and identified the heavy metal ATPase (HMA) family members in this plant. Our results demonstrated that <i>Oi>. <i>japonicusi> exhibited a Cd enrichment factor (EF) of 2.75, demonstrating strong potential for soil Cd pollution remediation. Nine heavy metal ATPase (HMA) members of P1B-ATPases were successfully identified from the transcriptome data of <i>Oi>. <i>japonicusi>, with OjHMA1-OjHMA6 classified as the Zn/Co/Cd/Pb-ATPases and OjHMA7-OjHMA9 as the Cu/Ag-ATPases. The expression levels of <i>OjHMA1i>, <i>OjHMA2i>, <i>OjHMA3i>, and <i>OjHMA7i> were significantly up-regulated under Cd stress, highlighting their crucial roles in cadmium ion absorption and transport. The topological analysis revealed that these proteins possessed characteristic transmembrane (TM) segments of the family, along with functional A, P, and N domains involved in regulating ion absorption and release. Metal ion-binding sites (M4, M5, and M6) existed on the TM segments. Based on the number of transmembrane domains and the residues at metal ion-binding sites, the plant HMA family members were categorized into three subgroups: P1B-1 ATPases, P1B-2 ATPases, and P1B-4 ATPases. Specifically, the P1B-1 ATPase subgroup included the motifs TM4(CPC), TM5(YN[X]₄P), and TM6(M[XX]SS); the P1B-2 ATPase subgroup featured the motifs TM4(CPC), TM5(K), and TM6(DKTGT); the P1B-4 ATPase subgroup contained the motifs TM4(SPC) and TM6(HE[X]GT), all of which were critical for protein functions. Molecular docking results revealed the importance of conserved sequences such as CPC/SPC, DKTGT, and HE[X]GT in metal ion coordination and stabilization. These findings provide potential molecular targets for enhancing Cd uptake and tolerance of <i>Oi>. <i>japonicusi> by genetic engineering and lay a theoretical foundation for developing new cultivars with high Cd accumulation capacity.
Cadmium/metabolism* ; Adenosine Triphosphatases/metabolism* ; Ophiopogon/drug effects* ; Soil Pollutants/toxicity* ; Plant Proteins/metabolism* ; Stress, Physiological ; Multigene Family ; Gene Expression Regulation, Plant

Geminiviruses cause substantial crop yield losses worldwide. The replication initiator protein (Rep) encoded by geminiviruses is indispensable for geminiviral replication. The Rep protein encoded by beet severe curly top virus (BSCTV, genus <i>Curtovirusi>, family <i>Geminiviridaei>) induces <i>VARIANT IN METHYLATION 5i> (<i>VIM5i>) expression in <i>Arabidopsisi> leaves upon BSCTV infection. VIM5 functions as a ubiquitination-related E3 ligase to promote the proteasomal degradation of methyltransferases, resulting in reduction of methylation levels in the BSCTV C2-3 promoter. However, the specific domains of Rep responsible for <i>VIM5i> induction remain poorly characterized. Although Rep proteins from several geminiviruses act as viral suppressors of RNA silencing (VSRs), whether BSCTV Rep also possesses VSR activity remains to be illustrated. In this study, we employed a transient expression system in the 16c-GFP transgenic and the wild-type <i>Nicotiana benthamianai> plants to analyze the VSR and the <i>VIM5i>-inducing activities of different truncated Rep proteins haboring distinct domains. We found that the N-terminal domain (amino acids 1-180) of Rep suppressed <i>GFPi> silencing in 16c-GFP transgenic <i>Ni>. <i>benthamianai> leaves. The minimal N-terminal fragment (amino acids 1-104) induced <i>VIM5i> expression upon co-infiltration, while C-terminal truncations lacked <i>VIM5i>-inducing activity. Our results indicate that the N-terminal domain of Rep encoded by BSCTV mediates the suppression of RNA silencing and induces <i>VIM5i> expression. Thus, our findings contribute to a better understanding of interactions between geminiviral Rep and plant hosts.
Geminiviridae/genetics* ; Nicotiana/metabolism* ; Arabidopsis/metabolism* ; RNA Interference ; Viral Proteins/metabolism* ; Arabidopsis Proteins/metabolism* ; Plants, Genetically Modified/metabolism* ; Protein Domains ; Plant Diseases/virology* ; Methyltransferases/metabolism* ; Ubiquitin-Protein Ligases/metabolism* ; DNA Helicases/genetics*