Different biological effects of exposure to far-UVC (222 nm) and near-UVC (254 nm) irradiation.

Ultraviolet C (UVC) light has long been used as a sterilizing agent, primarily through devices that emit at 254 nm. Depending on the dose and duration of exposure, UV 254 nm can cause erythema and photokeratitis and potentially cause skin cancer since it directly modifies nitrogenated nucleic acid bases. Filtered KrCl excimer lamps (emitting mainly at 222 nm) have emerged as safer germicidal tools and have even been proposed as devices to sterilize surgical wounds. All the studies that showed the safety of 222 nm analyzed cell number and viability, erythema generation, epidermal thickening, the formation of genetic lesions such as cyclobutane pyrimidine dimers (CPDs) and pyrimidine-(6-4)-pyrimidone photoproducts (6-4PPs) and cancer-inducing potential. Although nucleic acids can absorb and be modified by both UV 254 nm and UV 222 nm equally, compared to UV 254 nm, UV 222 nm is more intensely absorbed by proteins (especially aromatic side chains), causing photooxidation and cross-linking. Here, in addition to analyzing DNA lesion formation, for the first time, we evaluated changes in the proteome and cellular pathways, reactive oxygen species formation, and metalloproteinase (MMP) levels and activity in full-thickness in vitro reconstructed human skin (RHS) exposed to UV 222 nm. We also performed the longest (40 days) in vivo study of UV 222 nm exposure in the HRS/J mouse model at the occupational threshold limit value (TLV) for indirect exposure (25 mJ/cm2) and evaluated overall skin morphology, cellular pathological alterations, CPD and 6-4PP formation and MMP-9 activity. Our study showed that processes related to reactive oxygen species and inflammatory responses were more altered by UV 254 nm than by UV 222 nm. Our chronic in vivo exposure assay using the TLV confirmed that UV 222 nm causes minor damage to the skin. However, alterations in pathways related to skin regeneration raise concerns about direct exposure to UV 222 nm.

Suppression of citrus canker disease mediated by flagellin perception.

Citrus cancer, caused by strains of Xanthomonas citri (Xc) and Xanthomonas aurantifolii (Xa), is one of the most economically important citrus diseases. Although our understanding of the molecular mechanisms underlying citrus canker development has advanced remarkably in recent years, exactly how citrus plants fight against these pathogens remains largely unclear. Using a Xa pathotype C strain that infects Mexican lime only and sweet oranges as a pathosystem to study the immune response triggered by this bacterium in these hosts, we herein report that the Xa flagellin C protein (XaFliC) acts as a potent defence elicitor in sweet oranges. Just as Xa blocked canker formation when coinfiltrated with Xc in sweet orange leaves, two polymorphic XaFliC peptides designated flgIII-20 and flgIII-27, not related to flg22 or flgII-28 but found in many Xanthomonas species, were sufficient to protect sweet orange plants from Xc infection. Accordingly, ectopic expression of XaFliC in a Xc FliC-defective mutant completely abolished the ability of this mutant to grow and cause canker in sweet orange but not Mexican lime plants. Because XaFliC and flgIII-27 also specifically induced the expression of several defence-related genes, our data suggest that XaFliC acts as a main immune response determinant in sweet orange plants.

Systemic conditions associated with increased risk to develop oral squamous cell carcinoma: Systematic review and meta-analysis.

This study aimed to map systemic alterations predisposing to oral squamous cell carcinoma (OSCC) onset. This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Five databases were used to access (1) reports of OSCC co-occurring in patients with systemic conditions, (2) prevalence of OSCC among these patients, and (3) clinicopathological profiles. Data from more than 1 million patients worldwide showed that Fanconi's anemia, xeroderma pigmentosum, dyskeratosis congenital, chronic fatigue syndrome, and patients post bone marrow transplantation (BMT) present increased risk for OSCC development. The overall prevalence of OSCC in syndromic patients and post-BMT were 0.65% (95% CI = 0.13-3.11, p < 0.01) and 5.83% (95% CI = 0.00-30.90, p < 0.01), respectively. The certainty of the evidence was moderate. This study demonstrated that some systemic conditions predispose to OSCC. These results present an impact on the screening of OSCC in systemically compromised patients.

Mass spectrometry-based proteomics of 3D cell culture: A useful tool to validate culture of spheroids and organoids.

Worldwide obesity, defined as abnormal or excessive fat accumulation that may result in different comorbidities, is considered a pandemic condition that has nearly tripled in the last 45 years. Most studies on obesity use animal models or adipocyte monolayer cell culture to investigate adipose tissue. However, besides monolayer cell culture approaches do not fully recapitulate the physiology of living organisms, there is a growing need to reduce or replace animals in research. In this context, the development of 3D self-organized structures has provided models that better reproduce the in vitro aspects of the in vivo physiology in comparison to traditional monolayer cell culture. Besides, recent advances in omics technologies have allowed us to characterize these cultures at the proteome, metabolome, transcription factor, DNA-binding and transcriptomic levels. These two combined approaches, 3D culture and omics, have provided more realistic data about determined conditions. Thereby, here we focused on the development of an obesity study pipeline including proteomic analysis to validate adipocyte-derived spheroids. Through the combination of collected mass spectrometry data from differentiated 3T3-L1 spheroids and from murine white adipose tissue (WAT), we identified 1732 proteins in both samples. By using a comprehensive proteomic analysis, we observed that the in vitro 3D culture of differentiated adipocytes shares important molecular pathways with the WAT, including expression of proteins involved in central metabolic process of the adipose tissue. Together, our results show a combination of an orthogonal method and an image-based analysis that constitutes a useful pipeline to be applied in 3D adipocyte culture.

Extraoral photobiomodulation for prevention of oral and oropharyngeal mucositis in head and neck cancer patients: interim analysis of a randomized, double-blind, clinical trial.

PURPOSE: To assess the safety and efficacy of prophylactic extraoral photobiomodulation (PBM) for the prevention of oral and oropharyngeal mucositis (OM) on clinical outcomes and survival in patients with oral cavity and oropharyngeal squamous cell carcinoma (OOPSCC). METHODS: OOPSCC patients who received radiotherapy (RT) were prospectively randomized to two groups: prophylactic extraoral PBM and placebo. OM grade (NCI), pain (VAS), analgesia, and anti-inflammatory prescriptions were assessed weekly. Quality of life questionnaires (QoL) were performed at the first and last day of RT. Following RT, participants were evaluated quarterly for oncological outcomes follow-up. RESULTS: Fifty-five patients met the inclusion criteria. The first occurrence of OM was observed at week 1, for the placebo group (p = 0.014). Later, OM onset and severity was observed for the PBM group, with first occurrence at week 2 (p = 0.009). No difference in severe OM incidence was observed (p > 0.05). Lower mean pain score was noted at week 7 for the PBM group (2.1) compared to placebo group (4.5) (p = 0.009). Less analgesics (week 3; p = 0.009/week 7; p = 0.02) and anti-inflammatory prescription (week 5; p = 0.0346) were observed for the PBM group. Better QoL scores were observed for the PBM group at last day of RT (p = 0.0034). No difference in overall survival among groups was observed in 1 year of follow-up (p = 0.889). CONCLUSION: Prophylactic extraoral PBM can delay OM onset, reduce pain, and reduce analgesic and anti-inflammatory prescription requirements. Extraoral PBM was associated with better QoL. There was no evidence of PBM impact on oncological outcomes. TRIAL REGISTRATION: TRN:RBR-4w4swx (date of registration: 01/20/2020).

STAT3 contributes to cisplatin resistance, modulating EMT markers, and the mTOR signaling in lung adenocarcinoma.

Lung cancer is the second leading cause of cancer death worldwide and is strongly associated with cisplatin resistance. The transcription factor signal transducer and activator of transcription 3 (STAT3) is constitutively activated in cancer cells and coordinates critical cellular processes as survival, self-renewal, and inflammation. In several types of cancer, STAT3 controls the development, immunogenicity, and malignant behavior of tumor cells while it dictates the responsiveness to radio- and chemotherapy. It is known that STAT3 phosphorylation at Ser727 by mechanistic target of rapamycin (mTOR) is necessary for its maximal activation, but the crosstalk between STAT3 and mTOR signaling in cisplatin resistance remains elusive. In this study, using a proteomic approach, we revealed important targets and signaling pathways altered in cisplatin-resistant A549 lung adenocarcinoma cells. STAT3 had increased expression in a resistance context, which can be associated with a poor prognosis. STAT3 knockout (SKO) resulted in a decreased mesenchymal phenotype in A549 cells, observed by clonogenic potential and by the expression of epithelial-mesenchymal transition markers. Importantly, SKO cells did not acquire the mTOR pathway overactivation induced by cisplatin resistance. Consistently, SKO cells were more responsive to mTOR inhibition by rapamycin and presented impairment of the feedback activation loop in Akt. Therefore, rapamycin was even more potent in inhibiting the clonogenic potential in SKO cells and sensitized to cisplatin treatment. Mechanistically, STAT3 partially coordinated the cisplatin resistance phenotype via the mTOR pathway in non-small cell lung cancer. Thus, our findings reveal important targets and highlight the significance of the crosstalk between STAT3 and mTOR signaling in cisplatin resistance. The synergic inhibition of STAT3 and mTOR potentially unveil a potential mechanism of synthetic lethality to be explored for human lung cancer treatment.

Microbial enrichment and meta-omics analysis identify CAZymes from mangrove sediments with unique properties.

Although lignocellulose is the most abundant and renewable natural resource for biofuel production, its use remains under exploration because of its highly recalcitrant structure. Its deconstruction into sugar monomers is mainly driven by carbohydrate-active enzymes (CAZymes). To develop highly efficient and fast strategies to discover biomass-degrading enzymes for biorefinery applications, an enrichment process combined with integrative omics approaches was used to identify new CAZymes. The lignocellulolytic-enriched mangrove microbial community (LignoManG) established on sugarcane bagasse (SB) was enriched with lignocellulolytic bacteria and fungi such as Proteobacteria, Bacteroidetes, Basidiomycota, and Ascomycota. These microbial communities were able to degrade up to 55 % of the total SB, indicating the production of lignocellulolytic enzymes. Metagenomic analysis revealed that the LignoManG harbors 18.042 CAZyme sequences such as of cellulases, hemicellulases, carbohydrate esterases, and lytic polysaccharide monooxygenase. Similarly, our metaproteomic analysis depicted several enzymes from distinct families of different CAZy families. Based on the LignoManG data, a xylanase (coldXynZ) was selected, amplified, cloned, expressed, and biochemically characterized. The enzyme displayed psicrofilic properties, with the highest activity at 15 °C, retaining 77 % of its activity when incubated at 0 °C. Moreover, molecular modeling in silico indicated that coldXynZ is composed of a TIM barrel, which is a typical folding found in the GH10 family, and displayed similar structural features related to cold-adapted enzymes. Collectively, the data generated in this study represent a valuable resource for lignocellulolytic enzymes with potential biotechnological applications.

Impact of tumor site on the prognosis of salivary gland neoplasms: A systematic review and meta-analysis.

In numerous types of cancer, the primary tumor site can show a correlation with disease behavior and survival outcomes. In salivary gland tumors (SGTs) this association remains controversial. This study assessed the association between primary sites of SGTs and prognosis. Studies from five databases were assessed and a meta-analysis was performed using studies that presented 95 % confidence interval (95 % CI), hazard ratio (HR) and survival analysis. Gathered information from 46,361 patients showed that site had a prognostic impact on SGTs. Tumors involving minor salivary glands showed worse overall survival (HR = 1.60; 95 % CI = 1.17-2.19; p = 0.003), disease-specific survival (HR=1.63; 95 % CI = 1.12-2.37; p = 0.01), and cause-specific survival (HR=2.10; 95 % CI = 1.72-2.55; p = 0.00001). Tumors from major salivary glands showed better recurrence-free survival (HR=2.31; 95 % CI = 1.77-3.02; p = 0.00001), and locoregional control of disease (HR=2.66; 95 % CI = 1.20-5.91; p = 0.02). Our results showed that the primary site of SGTs has an impact on patient prognosis.

Tumor Microenvironment Proteomics: Lessons From Multiple Myeloma.

Although the "seed and soil" hypothesis was proposed by Stephen Paget at the end of the 19th century, where he postulated that tumor cells (seeds) need a propitious medium (soil) to be able to establish metastases, only recently the tumor microenvironment started to be more studied in the field of Oncology. Multiple myeloma (MM), a malignancy of plasma cells, can be considered one of the types of cancers where there is more evidence in the literature of the central role that the bone marrow (BM) microenvironment plays, contributing to proliferation, survival, migration, and drug resistance of tumor cells. Despite all advances in the therapeutic arsenal for MM treatment in the last years, the disease remains incurable. Thus, studies aiming a better understanding of the pathophysiology of the disease, as well as searching for new therapeutic targets are necessary and welcome. Therefore, the present study aimed to evaluate the protein expression profiling of mononuclear cells derived from BM of MM patients in comparison with these same cell types derived from healthy individuals, in order to fill this gap in MM treatment. Proteomic analysis was performed using the mass spectrometry technique and further analyses were done using bioinformatics tools, to identify dysregulated biological pathways and/or processes in the BM microenvironment of patients with MM as a result of the disease. Among the pathways identified in this study, we can highlight an upregulation of proteins related to protein biosynthesis, especially chaperone proteins, in patients with MM. Additionally, we also found an upregulation of several proteins involved in energy metabolism, which is one of the cancer hallmarks. Finally, with regard to the downregulated proteins, we can highlight mainly those involved in different pathways of the immune response, corroborating the data that has demonstrated that the immune system of MM is impaired and, therefore, the immunotherapies that have been studied recently for the treatment of the disease are extremely necessary in the search for a control and a cure for these patients who live with the disease.

Diagnostic and prognostic value of miRNAs on salivary gland tumors: a systematic review and meta-analysis.

PURPOSE: Different levels of miRNA expression have been described in salivary gland tumors as a potential diagnostic marker and predictor of survival. We systematically reviewed the literature to assess the diagnostic and prognostic value of miRNAs on salivary gland tumors. METHODS: An electronic search was conducted in PubMed, Scopus, Embase, Cochrane, and Web of Science databases. In the meta-analysis, we assumed random-effects model with adjusted hazard ratio (HR) and 95% confidence intervals (95% CI). For prognostic studies, the risk of bias was assessed by Meta-Analysis of Statistics Assessment and Review Instrument (MAStARI) and Quality Assessment Tool for Diagnostic Accuracy Studies-2 (QUADAS-2) was utilized for diagnostic studies. RESULTS: Gathered data from 1.131 patients in seven studies demonstrated that different levels of miRNA expression presented diagnostic and prognostic in SGTs. The meta-analysis showed that altered miRNA expression were associated with shortened survival (HR, 2.35, 95% CI, 1.77-3.10, P < .00001). For diagnostic meta-analysis, the overall pooled results for specificity and sensibility were 0.87-0.97 (95% CI, 0.72-1) and 0.68-0.91 (95% CI, 0.51-0.96), respectively. CONCLUSION: MicroRNAs may be useful in prognostication of patients with SGTs; however, the diagnostic value of miRNAs in SGTs is still limited.

Epigenetic alterations in ameloblastomas: A literature review.

BACKGROUND: Ameloblastoma is a locally aggressive tumor, originated from odontogenic epithelium, and affects the jawbones with an elevated recurrence rate. The molecular mechanisms involved with the pathogenesis of this tumor remain undetermined. This review aimed to describe the current data regarding epigenetic alterations in ameloblastoma. MATERIAL AND METHODS: A systematized electronic search was performed in the English-language literature in three databases, combining the following keywords: ameloblastoma, epigenetic, methylation, noncoding RNA, histone acetylation. RESULTS: According to the gathered results of 11 studies in this review, epigenetic alterations could induce the development and progression of ameloblastoma. DNA methylation has been the most assessed mechanism in ameloblastomas. CONCLUSIONS: Current literature data indicate that epigenetic events can be involved in the etiopathogenesis of ameloblastomas. Key words:Ameloblastoma, epigenetic, methylation, noncoding RNA, histone acetylation.

Salivary alpha-1-antitrypsin and macrophage migration inhibitory factor may be potential prognostic biomarkers for oncologic treatment-induced severe oral mucositis.

AIMS: Evaluate the abundance of the selected targets, alpha-1-antitrypsin (A1AT) and macrophage migration inhibitory factor (MIF), and correlate these findings with the risk of developing severe oral mucositis (OM). MATERIALS AND METHODS: Head and neck squamous cell carcinoma (HNSCC) patients submitted to radiotherapy (RT) or chemoradiotherapy (CRT) were assessed. OM grade and pain were evaluated daily during treatment. Two protein targets, A1AT and MIF, were evaluated, using selected reaction monitoring-mass spectrometry (SRM-MS), in whole saliva, collected prior to oncologic treatment. The results obtained from the targeted proteomic analysis were correlated with OM clinical outcomes. RESULTS: A total of 27 patients were included, of whom 21 (77.8%) had locally advanced disease (clinical stage III or IV). Most patients (70.4%) received CRT. OM grades 2 (40.8%) and 3 (33.3%) were the most prevalent during RT with a mean highest reported OM-related pain of 3.22 through the visual analogue scale (VAS). The abundance of A1AT and MIF correlated significantly with severe (grades 3 or 4, p < 0.02) compared with moderate-low (grades 1 or 2, p < 0.04) OM grade. CONCLUSIONS: There is a correlation between the abundance of salivary A1AT and MIF and oncologic treatment-induced OM. The correlation of MIF expression with severe OM appears to be compatible with its physiological pro-inflammatory role. These results open up great possibilities for the use of salivary MIF and A1AT levels as prognostic markers for effective therapeutic interventions, such as photobiomodulation therapy, patient-controlled analgesia, or personalized medicaments.

Impact of pandemic COVID-19 outbreak on oral mucositis preventive and treatment protocols: new perspectives for extraoral photobiomodulation therapy.

This communication discusses the current challenges of oral mucositis (OM) management during the pandemic COVID-19 outbreak and reflects about an extraoral photobiomodulation protocol as an optimal alternative for preventing and treating OM in advanced cancer patients while minimizing the risk of infection by avoiding intraoral manipulation.

Novel LRAP-binding partner revealing the plasminogen activation system as a regulator of cementoblast differentiation and mineral nodule formation in vitro.

Amelogenin isoforms, including full-length amelogenin (AMEL) and leucine-rich amelogenin peptide (LRAP), are major components of the enamel matrix, and are considered as signaling molecules in epithelial-mesenchymal interactions regulating tooth development and periodontal regeneration. Nevertheless, the molecular mechanisms involved are still poorly understood. The aim of the present study was to identify novel binding partners for amelogenin isoforms in the cementoblast (OCCM-30), using an affinity purification assay (GST pull-down) followed by mass spectrometry and immunoblotting. Protein-protein interaction analysis for AMEL and LRAP evidenced the plasminogen activation system (PAS) as a potential player regulating OCCM-30 response to amelogenin isoforms. For functional assays, PAS was either activated (plasmin) or inhibited (ε-aminocaproic acid [aminocaproic]) in OCCM-30 cells and the cell morphology, mineral nodule formation, and gene expression were assessed. PAS inhibition (EACA 100 mM) dramatically decreased mineral nodule formation and expression of OCCM-30 differentiation markers, including osteocalcin (Bglap), bone sialoprotein (Ibsp), osteopontin (Spp1), tissue-nonspecific alkaline phosphatase (Alpl) and collagen type I (Col1a1), and had no effect on runt-related transcription factor 2 (Runx2) and Osterix (Osx) mRNA levels. PAS activation (plasmin 5 µg/µl) significantly increased Col1a1 and decreased Bglap mRNA levels (p < .05). Together, our findings shed new light on the potential role of plasminogen signaling pathway in the control of the amelogenin isoform-mediated response in cementoblasts and provide new insights into the development of targeted therapies.

Mass spectrometry-based proteome profile may be useful to differentiate adenoid cystic carcinoma from polymorphous adenocarcinoma of salivary glands.

OBJECTIVE: The aim of this study was to determine the proteome of adenoid cystic carcinoma (AdCC) and polymorphous adenocarcinoma (PAc) and to identify a protein signature useful in distinguishing these two neoplasms. STUDY DESIGN: Ten cases of AdCC and 10 cases of PAc were microdissected for enrichment of neoplastic tissue. The samples were submitted to liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the proteomics data were analyzed by using the MaxQuant software. LC-MS/MS spectra were searched against the Human UniProt database, and statistical analyses were performed with Perseus software. Bioinformatic analyses were performed by using discovery-based proteomic data on both tumors. RESULTS: LC-MS/MS analysis identified 1957 proteins. The tumors shared 1590 proteins, and 261 were exclusively identified in AdCC and 106 in PAc. Clustering analysis of the statistically significant proteins clearly separated AdCC from PAc. Protein expression 10 times higher in one group than in the other led to a signature of 16 proteins-6 upregulated in AdCC and 10 in PAc. A new clustering analysis showed reverse regulation and also differentiated both tumors. CONCLUSIONS: Global proteomics may be useful in discriminating these two malignant salivary neoplasms that frequently show clinical and microscopic overlaps, but additional validation studies are still necessary to determine the diagnostic potential of the protein signature obtained.

Tumor safety and side effects of photobiomodulation therapy used for prevention and management of cancer treatment toxicities. A systematic review.

Photobiomodulation therapy (PBMT), also known as low-level laser therapy (LLLT), has been increasingly used for the treatment of toxicities related to cancer treatment. One of the challenges for the universal acceptance of PBMT use in cancer patients is whether or not there is a potential for the light to stimulate the growth of residual malignant cells that evaded oncologic treatment, increasing the risk for tumor recurrences and development of a second primary tumor. Current science suggests promising effects of PBMT in the prevention and treatment of breast cancer-related lymphedema and oral mucositis, among other cancer treatment toxicities. Nevertheless, this seems to be the first systematic review to analyze the safety of the use of PBMT for the management of cancer-related toxicities. Scopus, MEDLINE/PubMed, and Embase were searched electronically. A total of 27 articles met the search criteria. Selected studies included the use of PBMT for prevention and treatment of oral mucositis, lymphedema, radiodermatitis, and peripheral neuropathy. Most studies showed that no side effects were observed with the use of PBMT. The results of this systematic review, based on current literature, suggest that the use of PBMT in the prevention and management of cancer treatment toxicities does not lead to the development of tumor safety issues.

Rab5C enhances resistance to ionizing radiation in rectal cancer.

Rectal cancer represents one third of the colorectal cancers that are diagnosed. Neoadjuvant chemoradiation is a well-established protocol for rectal cancer treatment reducing the risk of local recurrence. However, a pathologic complete response is only achieved in 10-40% of cases and the mechanisms associated with resistance are poorly understood. To identify potential targets for preventing therapy resistance, a proteomic analysis of biopsy specimens collected from stage II and III rectal adenocarcinoma patients before neoadjuvant treatment was performed and compared with residual tumor tissues removed by surgery after neoadjuvant therapy. Three proteins, Ku70, Ku80, and Rab5C, exhibited a significant increase in expression after chemoradiation. To better understand the role of these proteins in therapy resistance, a rectal adenocarcinoma cell line was irradiated to generate a radiotherapy-resistant lineage. These cells overexpressed the same three proteins identified in the tissue samples. Furthermore, radiotherapy resistance in this in vitro model was found to involve modulation of epidermal growth factor receptor (EGFR) internalization by Rab5C in response to irradiation, affecting expression of the DNA repair proteins, Ku70 and Ku80, and cell resistance. Taken together, these findings indicate that EGFR and Rab5C are potential targets for the sensitization of rectal cancer cells and they should be further investigated. KEY MESSAGES: • Rab5C orchestrates a mechanism of radioresistance in rectal adenocarcinoma cell. • Rab5C modulates EGFR internalization and its relocalization to the nucleus. • In the nucleus, EGFR can modulate the expression of the DNA repair proteins, Ku70 and Ku80. • Rab5C, Ku70, and Ku80 are overexpressed in tumor tissues that contain tumor cells that are resistant to chemoradiation treatment.

Human mitochondrial pyruvate carrier 2 as an autonomous membrane transporter.

The active transport of glycolytic pyruvate across the inner mitochondrial membrane is thought to involve two mitochondrial pyruvate carrier subunits, MPC1 and MPC2, assembled as a 150 kDa heterotypic oligomer. Here, the recombinant production of human MPC through a co-expression strategy is first described; however, substantial complex formation was not observed, and predominantly individual subunits were purified. In contrast to MPC1, which co-purifies with a host chaperone, we demonstrated that MPC2 homo-oligomers promote efficient pyruvate transport into proteoliposomes. The derived functional requirements and kinetic features of MPC2 resemble those previously demonstrated for MPC in the literature. Distinctly, chemical inhibition of transport is observed only for a thiazolidinedione derivative. The autonomous transport role for MPC2 is validated in cells when the ectopic expression of human MPC2 in yeast lacking endogenous MPC stimulated growth and increased oxygen consumption. Multiple oligomeric species of MPC2 across mitochondrial isolates, purified protein and artificial lipid bilayers suggest functional high-order complexes. Significant changes in the secondary structure content of MPC2, as probed by synchrotron radiation circular dichroism, further supports the interaction between the protein and ligands. Our results provide the initial framework for the independent role of MPC2 in homeostasis and diseases related to dysregulated pyruvate metabolism.

Ceratocystis cacaofunesta genome analysis reveals a large expansion of extracellular phosphatidylinositol-specific phospholipase-C genes (PI-PLC).

BACKGROUND: The Ceratocystis genus harbors a large number of phytopathogenic fungi that cause xylem parenchyma degradation and vascular destruction on a broad range of economically important plants. Ceratocystis cacaofunesta is a necrotrophic fungus responsible for lethal wilt disease in cacao. The aim of this work is to analyze the genome of C. cacaofunesta through a comparative approach with genomes of other Sordariomycetes in order to better understand the molecular basis of pathogenicity in the Ceratocystis genus. RESULTS: We present an analysis of the C. cacaofunesta genome focusing on secreted proteins that might constitute pathogenicity factors. Comparative genome analyses among five Ceratocystidaceae species and 23 other Sordariomycetes fungi showed a strong reduction in gene content of the Ceratocystis genus. However, some gene families displayed a remarkable expansion, in particular, the Phosphatidylinositol specific phospholipases-C (PI-PLC) family. Also, evolutionary rate calculations suggest that the evolution process of this family was guided by positive selection. Interestingly, among the 82 PI-PLCs genes identified in the C. cacaofunesta genome, 70 genes encoding extracellular PI-PLCs are grouped in eight small scaffolds surrounded by transposon fragments and scars that could be involved in the rapid evolution of the PI-PLC family. Experimental secretome using LC-MS/MS validated 24% (86 proteins) of the total predicted secretome (342 proteins), including four PI-PLCs and other important pathogenicity factors. CONCLUSION: Analysis of the Ceratocystis cacaofunesta genome provides evidence that PI-PLCs may play a role in pathogenicity. Subsequent functional studies will be aimed at evaluating this hypothesis. The observed genetic arsenals, together with the analysis of the PI-PLC family shown in this work, reveal significant differences in the Ceratocystis genome compared to the classical vascular fungi, Verticillium and Fusarium. Altogether, our analyses provide new insights into the evolution and the molecular basis of plant pathogenicity.