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1.
Children (Basel) ; 9(8)2022 Jul 23.
Article in English | MEDLINE | ID: mdl-35892611

ABSTRACT

TITF1 (Thyroid Transcription Factor-1) is a homeodomain-containing transcription factor. Previous studies showed that Titf1 null mice are characterized by failure of tracheo-oesophageal separation and impaired lung morphogenesis resulting in Pulmonary Hypoplasia (PH). In this study, we aim to evaluate the role of TITF1 in the pathogenesis of congenital diaphragmatic hernia (CDH) in humans. We investigated TITF1 expression in human trachea and lungs and performed direct mutation analysis in a CDH population. We studied 13 human fetuses at 14 to 24 weeks of gestation. Five µm sections were fixed in paraformaldehyde and incubated with anti-TITF1 primary antibody. Positive staining was visualized by biotinylated secondary antibody. We also performed TITF1 screening on genomic DNA extracted from peripheral blood of 16 patients affected by CDH and different degrees of PH, searching for mutations, insertions, and/or deletions, by sequencing the exonic regions of the gene. Histochemical studies showed positive brown staining of fetal follicular thyroid epithelium, normal fetal trachea, and normal fetal lung bronchial epithelium. Fetal esophageal wall was immunohistochemically negative. Molecular genetic analysis showed complete identity between the sequences obtained and the Wild Type (WT) form of the gene in all cases. No mutation, insertion and/or deletion was detected. Although TITF1 is expressed in the human fetal lung and has been considered to have a role in the pathogenesis of PH in CDH, the results of our study do not support the hypothesis that TITF1 mutations play a key role in the etiopathogenesis of CDH.

2.
Mol Biol Rep ; 48(11): 7087-7093, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34515921

ABSTRACT

BACKGROUND: In adulthood the activity of the lactase enzyme is inherited as autosomal dominant form associated to Single nucleotide polymorphisms (SNPs). The present research was aimed to develop a novel genetic method to test lactase non persistence more powerfully. METHODS AND RESULTS: In our study, we selected eight different SNPs that are associated with lactase persistence from Caucasian, Arabian Bedouins, sub-Saharian Africans and Asian populations to set up an approach to detect all the eight different SNPs at the same time in the same sample. This technique is centred on the identification of SNPs with a single nucleotide primer extension method using Sanger sequencing and capillary electrophoresis. CONCLUSIONS: Our method allowed us to check the genotype asset of eight SNPs related to lactase persistence simultaneously and in a very efficient manner. It could be applied to a higher number of SNPs in a single reaction.


Subject(s)
Lactase/deficiency , Lactose Intolerance , Polymorphism, Single Nucleotide , Adult , Female , Humans , Lactase/chemistry , Lactase/genetics , Lactase/metabolism , Lactose Intolerance/enzymology , Lactose Intolerance/genetics , Male , Middle Aged
3.
Cancers (Basel) ; 13(15)2021 Jul 27.
Article in English | MEDLINE | ID: mdl-34359670

ABSTRACT

Telomerase reactivation during hepatocarcinogenesis is recurrently caused by two point mutations occurring most frequently at the nucleotide -124 (95%) and occasionally at the nucleotide -146 (<5%) upstream of the TERT translational start site in hepatocellular carcinoma (HCC). In this study, we designed a droplet digital PCR (ddPCR) assay to detect TERT promoter (TERTp) nucleotide change G>A at position -124 and to quantify the mutant allele frequency (MAF) in 121 primary liver cancers, including 114 HCC along with 23 autologous cirrhotic tissues, five cholangiocarcinoma (CC), and two hepato-cholangiocarcinoma (HCC-CC). All cases were evaluated for tumour markers such as α-fetoprotein (AFP), carbohydrate antigen 19-9 (CA19-9), and carcinoembryonic antigen (CEA). We compared the sensitivity of ddPCR and Sanger sequencing and investigated the prognostic relevance of TERTp mutations. The TERTp G>A transition was identified in 63.6% and 52.1% of HCC samples by ddPCR and Sanger sequencing, respectively. One out of 23 (4.3%) peri-tumour tissues tested positive only by ddPCR. One out of five CC (20%) and none of the HCC-CC were found concordantly mutated by the two methods. The TERTp MAF ranged from 2% to 66%, and the large majority (85.5%) of mutated samples showed a value above 20%. A statistically significant correlation was found between TERTp mutation and tumour size (p = 0.048), while an inverse correlation was observed with CA19-9 levels (p = 0.0105). Moreover, HCC patients with TERTp -124A had reduced survival. In conclusion, the single nucleotide variation G>A at position -124 in TERTp, detected either by ddPCR or by Sanger sequencing, showed a remarkable high frequency in HCC. Such mutation is associated with lower levels of CA19-9 and reduced survival in HCC patients suggesting that the TERTp status may represent a distinct signature of liver cancer subgroups.

4.
Environ Pollut ; 287: 117151, 2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34020261

ABSTRACT

Fuel additive methylcyclopentadienyl manganese tricarbonyl (MMT) is counted as an organic manganese (Mn)-derived compound. The toxic effects of Mn (alone and complexed) on dopaminergic (DA) neurotransmission have been investigated in both cellular and animal models. However, the impact of environmentally relevant Mn exposure on DA neurodevelopment is rather poorly understood. In the present study, the MMT dose of 100 µM (about 5 mg Mn/L) caused up-regulation of DA-related genes in association with cell body swelling and increase in the number of DA neurons of the ventral diencephalon subpopulation DC2. Furthermore, our analysis identified significant brain Mn bioaccumulation and enhancement of total dopamine levels in association with locomotor hyperactivity. Although DA levels were restored at adulthood, we observed a deficit in the acquisition and consolidation of memory. Collectively, these findings suggest that developmental exposure to low-level MMT-derived Mn is responsible for the selective alteration of diencephalic DA neurons and with long-lasting effects on fish explorative behaviour in adulthood.


Subject(s)
Manganese , Organometallic Compounds , Animals , Diencephalon , Dopaminergic Neurons , Manganese/toxicity , Zebrafish
5.
Foods ; 10(3)2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33802000

ABSTRACT

The common dentex (Dentex dentex (Linnaeus, 1758)) is an iconic fish in the Mediterranean diet. Due to its commercial and organoleptic importance, this sparid is highly appreciated in European markets and is often subjected to species substitution frauds. Comparative mitogenomics is a suitable approach for identifying new and effective barcode markers. This study aimed to find a molecular tag useful for unequivocally discriminating the sparid species D. dentex. The comparison of the complete mitochondrial DNA (mtDNA) sequences of 16 sparid species allowed us to highlight the potential of the NAD2 gene for direct identification purposes. Common dentex-specific primers were created and successfully evaluated by end-point and real-rime PCR (Polymerase Chain Reaction) for several fish species, achieving amplification only in the D. dentex. The method proposed in this study appears fast, simple, and inexpensive and requires affordable instrumentation. This approach provides unambiguous results for the common dentex authentication without the sequencing step. The presence/absence assay for D. dentex can be executed in a few hours of lab work. Therefore, national authorities responsible for food safety and traceability could apply and make full use of DNA-testing methods for deterring operators from false seafood declarations.

6.
Nutrients ; 13(4)2021 Apr 14.
Article in English | MEDLINE | ID: mdl-33919766

ABSTRACT

Many patients with inflammatory bowel disease (IBD) restrict dairy products to control their symptoms. The aim of the study was to investigate the prevalence of lactose intolerance assessed with hydrogen breath test (H-BT) in IBD patients in clinical remission compared to a sex, age and BMI matched control population. We further detected the prevalence of three single nucleotide polymorphisms of the lactase (LCT) gene: the lactase non persistence LCT-13910 CC (wildtype) and the intermediate phenotype LCT-22018 CT and LCT-13910 AG; finally, we assess the correlation between genotype and H-BT. A total of 54 IBD patients and 69 control who underwent clinical evaluation, H-BT and genetic test were enrolled. H-BT was positive in 64.8% IBD patients and 62.3% control (p = 0.3). The wild-type genotype was found in 85.2% IBD patients while CT-22018, AG-13910 and CT-22018/AG-13910 polymorphisms were found in 9.3%, 1.8% and 3.7%. In the control group, the wild-type genotype, CT-22018, AG-13910 and CT-22018/AG-13910 polymorphisms were found in 87%, 5.8%, 5.8% and 1.4% of cases, respectively. Therefore, the wild-type and polymorphisms' prevalence did not differ between IBD population and control group (85.2% vs. 87%, p = 0.1) (14.8% vs. 13%, p = 0.7). The correlation between positive H-BT and genetic analysis showed that the wild-type genotype was associated with higher rate of lactose intolerance in the total population (OR 5.31, 95%CI 1.73-16.29, p = 0.003) and in the IBD (OR 7.61, 95%CI 1.36-42.7, p = 0.02). The prevalence of lactose intolerance in IBD patients did not differ from that of control. Despite suggestive symptoms, about 1/3 of IBD patients are not lactose intolerant, thus not needing "a priori" elimination diet. This may encourage a rationale and balanced dietary management in IBD.


Subject(s)
Inflammatory Bowel Diseases/diet therapy , Lactase/genetics , Lactose Intolerance/epidemiology , Lactose/adverse effects , Adult , Breath Tests/methods , Genetic Testing/statistics & numerical data , Humans , Hydrogen/analysis , Inflammatory Bowel Diseases/complications , Lactase/metabolism , Lactose/metabolism , Lactose Intolerance/complications , Lactose Intolerance/diagnosis , Lactose Intolerance/genetics , Male , Middle Aged , Polymorphism, Single Nucleotide , Prevalence , Prospective Studies , Young Adult
7.
Sci Rep ; 11(1): 1681, 2021 01 18.
Article in English | MEDLINE | ID: mdl-33462289

ABSTRACT

Due to their abundance in the oceans, their extraordinary biodiversity and the increasing use for biotech applications, the study of diatom biology is receiving more and more attention in the recent years. One of the limitations in developing molecular tools for diatoms lies in the peculiar nature of their cell wall, that is made of silica and organic molecules and that hinders the application of standard methods for cell lysis required, for example, to extract organelles. In this study we present a protocol for intact nuclei isolation from diatoms that was successfully applied to three different species: two pennates, Pseudo-nitzschia multistriata and Phaeodactylum tricornutum, and one centric diatom species, Chaetoceros diadema. Intact nuclei were extracted by treatment with acidified NH4F solution combined to low intensity sonication pulses and separated from cell debris via FAC-sorting upon incubation with SYBR Green. Microscopy observations confirmed the integrity of isolated nuclei and high sensitivity DNA electrophoresis showed that genomic DNA extracted from isolated nuclei has low degree of fragmentation. This protocol has proved to be a flexible and versatile method to obtain intact nuclei preparations from different diatom species and it has the potential to speed up applications such as epigenetic explorations as well as single cell ("single nuclei") genomics, transcriptomics and proteomics in different diatom species.


Subject(s)
Cell Fractionation/methods , Cell Nucleus/chemistry , Diatoms/cytology , Cell Fractionation/standards , Cell Nucleus/genetics , Cell Nucleus/metabolism , DNA/genetics , DNA/metabolism , Diatoms/genetics , Diatoms/metabolism , Microscopy, Confocal , Subcellular Fractions/metabolism
8.
Sci Rep ; 11(1): 807, 2021 01 12.
Article in English | MEDLINE | ID: mdl-33437054

ABSTRACT

Concerted evolution is a process of homogenisation of repetitive sequences within a genome through unequal crossing over and gene conversion. This homogenisation is never fully achieved because mutations always create new variants. Classically, concerted evolution has been detected as "noise" in electropherograms and these variants have been characterised through cloning and sequencing of subsamples of amplified products. However, this approach limits the number of detectable variants and provides no information about the abundance of each variant. In this study, we investigated concerted evolution by using environmental time-series metabarcoding data, single strain high-throughput sequencing (HTS) and a collection of Sanger reference barcode sequences. We used six species of the marine planktonic diatom genus Chaetoceros as study system. Abundance plots obtained from environmental metabarcoding and single strain HTS showed the presence of a haplotype far more abundant than all the others (the "dominant" haplotype) and identical to the reference sequences of that species obtained with Sanger sequencing. This distribution fitted best with Zipf's law among the rank abundance/ dominance models tested. Furthermore, in each strain 99% of reads showed a similarity of 99% with the dominant haplotype, confirming the efficiency of the homogenisation mechanism of concerted evolution. We also demonstrated that minor haplotypes found in the environmental samples are not only technical artefacts, but mostly intragenomic variation generated by incomplete homogenisation. Finally, we showed that concerted evolution can be visualised inferring phylogenetic networks from environmental data. In conclusion, our study provides an important contribution to the understanding of concerted evolution and to the interpretation of DNA barcoding and metabarcoding data based on multigene family markers.


Subject(s)
DNA, Ribosomal/genetics , Diatoms/genetics , DNA, Ribosomal Spacer/genetics , Evolution, Molecular , Genetic Variation , High-Throughput Nucleotide Sequencing/methods , Phylogeny
9.
Foods ; 9(10)2020 Oct 02.
Article in English | MEDLINE | ID: mdl-33023115

ABSTRACT

The commercialization of porgies or seabreams of the family Sparidae has greatly increased in the last decade, and some valuable species have become subject to seafood substitution. DNA regions currently used for fish species identification in fresh and processed products belong to the mitochondrial (mt) genes cytochrome b (Cytb), cytochrome c oxidase I (COI), 16S and 12S. However, these markers amplify for fragments with lower divergence within and between some species, failing to provide informative barcodes. We adopted comparative mitogenomics, through the analysis of complete mtDNA sequences, as a compatible approach toward studying new barcoding markers. The intent is to develop a specific and rapid assay for the identification of the common pandora Pagellus erythrinus, a sparid species frequently subject to fraudulent replacement. The genetic diversity analysis (Hamming distance, p-genetic distance, gene-by-gene sequence variability) between 16 sparid mtDNA genomes highlighted the discriminating potential of a 291 bp NAD2 gene fragment. A pair of species-specific primers were successfully designed and tested by end-point and real-time PCR, achieving amplification only in P. erythrinus among several fish species. The use of the NAD2 barcoding marker provides a rapid presence/absence method for the identification of P. erythrinus.

10.
Nat Commun ; 9(1): 5050, 2018 11 28.
Article in English | MEDLINE | ID: mdl-30487611

ABSTRACT

A broad diversity of sex-determining systems has evolved in eukaryotes. However, information on the mechanisms of sex determination for unicellular microalgae is limited, including for diatoms, key-players of ocean food webs. Here we report the identification of a mating type (MT) determining gene for the diatom Pseudo-nitzschia multistriata. By comparing the expression profile of the two MTs, we find five MT-biased genes, of which one, MRP3, is expressed exclusively in MT+ strains in a monoallelic manner. A short tandem repeat of specific length in the region upstream of MRP3 is consistently present in MT+ and absent in MT- strains. MRP3 overexpression in an MT- strain induces sex reversal: the transgenic MT- can mate with another MT- strain and displays altered regulation of the other MT-biased genes, indicating that they lie downstream. Our data show that a relatively simple genetic program is involved in defining the MT in P. multistriata.


Subject(s)
Diatoms/physiology , Diatoms/genetics , Phylogeny , Transcriptome/genetics
11.
Front Genet ; 9: 310, 2018.
Article in English | MEDLINE | ID: mdl-30154826

ABSTRACT

MicroRNA (miRNA) has emerged as an important regulator of gene expression in neurodegenerative disease as amyotrophic lateral sclerosis (ALS). In the nervous system, dysregulation in miRNA-related pathways is subordinated to neuronal damage and cell death, which contributes to the expansion of neurodegenerative disorders, such as ALS. In the present research, we aimed to profile dysregulation of miRNAs in ALS blood and neuromuscular junction as well as healthy blood control by next-generation sequencing (NGS). The expression of three upregulated miRNAs, as miR-338-3p, miR-223-3p, and miR-326, in the ALS samples compared to healthy controls, has been validated by qRT-PCR in a cohort of 45 samples collected previously. Bioinformatics tools were used to perform ALS miRNAs target analysis and to predict novel miRNAs secondary structure. The analysis of the NGS data identified 696 and 49 novel miRNAs which were differentially expressed in ALS tissues. In particular, in neuromuscular junction the differential expression of miR-338-3p, which we previously found upregulated in different types of ASL tissues, miR-223-3p, and miR-326 was elevated compared to normal control. ALS miRNAs gene target were significantly involved in neuronal related pathway as BDFN1 and HIF-1genes. This study presents the direct experimental evidence that, overall, miR-338-3p is highly expressed in ALS tissues including neuromuscular junction characterizing ALS from normal tissues. Beside, our analysis identified, for the first time, novel miRNAs highly expressed in ALS tissues. In conclusion, the results indicate that miRNAs has an important role in the diagnosis and treatment of ALS.

12.
Oncotarget ; 9(27): 19255-19262, 2018 Apr 10.
Article in English | MEDLINE | ID: mdl-29721199

ABSTRACT

Thyroid cancer is the most common malignancy of the endocrine system and includes well-differentiated forms, namely papillary and follicular carcinomas, and the poorly differentiated and undifferentiated forms that result from the transformation of thyroid follicular cells (anaplastic carcinomas). Notably, 5-10% of all thyroid cancers are medullary thyroid cancers that arise from parafollicular cells also known as C cells. The most common genetic mutations in papillary and follicular thyroid cancers are point mutations of the BRAF or RAS genes, while the most common chromosomal alterations are RET/PTC and PAX8/PPARγ rearrangements. The most frequent initial manifestation of thyroid cancer is the appearance of a nodule most of which are benign; indeed, less than 5% are malignant. However, some cases are misdiagnosed, and many patients undergo unnecessary surgery. Therefore, an accurate pre-surgery evaluation is crucial. The most reliable diagnostic test for thyroid nodules is fine needle aspiration (FNA) cytology, which accurately distinguishes between a benign and malignant lesion in most cases. However, cytological discrimination between malignant and benign follicular cancer is often difficult because of poor quality samples. Here we describe rapid methods to create a positive control and identify the PAX8/PPARγ rearrangement in FNA thyroid samples by molecular biology.

13.
PLoS One ; 12(9): e0184090, 2017.
Article in English | MEDLINE | ID: mdl-28873438

ABSTRACT

Starfish have been instrumental in many fields of biological and ecological research. Oocytes of Astropecten aranciacus, a common species native to the Mediterranean Sea and the East Atlantic, have long been used as an experimental model to study meiotic maturation, fertilization, intracellular Ca2+ signaling, and cell cycle controls. However, investigation of the underlying molecular mechanisms has often been hampered by the overall lack of DNA or protein sequences for the species. In this study, we have assembled a transcriptome for this species from the oocytes, eggs, zygotes, and early embryos, which are known to have the highest RNA sequence complexity. Annotation of the transcriptome identified over 32,000 transcripts including the ones that encode 13 distinct cyclins and as many cyclin-dependent kinases (CDK), as well as the expected components of intracellular Ca2+ signaling toolkit. Although the mRNAs of cyclin and CDK families did not undergo significant abundance changes through the stages from oocyte to early embryo, as judged by real-time PCR, the transcript encoding Mos, a negative regulator of mitotic cell cycle, was drastically reduced during the period of rapid cleavages. Molecular phylogenetic analysis using the homologous amino acid sequences of cytochrome oxidase subunit I from A. aranciacus and 30 other starfish species indicated that Paxillosida, to which A. aranciacus belongs, is not likely to be the most basal order in Asteroidea. Taken together, the first transcriptome we assembled in this species is expected to enable us to perform comparative studies and to design gene-specific molecular tools with which to tackle long-standing biological questions.


Subject(s)
Embryo, Nonmammalian/metabolism , Ovum/metabolism , Starfish/genetics , Starfish/metabolism , Transcriptome/genetics , Animals , Calcium Signaling/genetics , Cyclin-Dependent Kinases/metabolism , Cyclins/metabolism , Databases, Nucleic Acid , Electron Transport Complex IV/chemistry , Electron Transport Complex IV/genetics , Gene Expression Profiling , Gene Expression Regulation, Developmental , Gene Ontology , Molecular Sequence Annotation , Phylogeny , RNA, Messenger/genetics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Reproducibility of Results
14.
Appl Environ Microbiol ; 83(17)2017 09 01.
Article in English | MEDLINE | ID: mdl-28667110

ABSTRACT

Bacterioplankton are fundamental components of marine ecosystems and influence the entire biosphere by contributing to the global biogeochemical cycles of key elements. Yet, there is a significant gap in knowledge about their diversity and specific activities, as well as environmental factors that shape their community composition and function. Here, the distribution and diversity of surface bacterioplankton along the coastline of the Gulf of Naples (GON; Italy) were investigated using flow cytometry coupled with high-throughput sequencing of the 16S rRNA gene. Heterotrophic bacteria numerically dominated the bacterioplankton and comprised mainly Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes Distinct communities occupied river-influenced, coastal, and offshore sites, as indicated by Bray-Curtis dissimilarity, distance metric (UniFrac), linear discriminant analysis effect size (LEfSe), and multivariate analyses. The heterogeneity in diversity and community composition was mainly due to salinity and changes in environmental conditions across sites, as defined by nutrient and chlorophyll a concentrations. Bacterioplankton communities were composed of a few dominant taxa and a large proportion (92%) of rare taxa (here defined as operational taxonomic units [OTUs] accounting for <0.1% of the total sequence abundance), the majority of which were unique to each site. The relationship between 16S rRNA and the 16S rRNA gene, i.e., between potential metabolic activity and abundance, was positive for the whole community. However, analysis of individual OTUs revealed high rRNA-to-rRNA gene ratios for most (71.6% ± 16.7%) of the rare taxa, suggesting that these low-abundance organisms were potentially active and hence might be playing an important role in ecosystem diversity and functioning in the GON.IMPORTANCE The study of bacterioplankton in coastal zones is of critical importance, considering that these areas are highly productive and anthropogenically impacted. Their richness and evenness, as well as their potential activity, are very important to assess ecosystem health and functioning. Here, we investigated bacterial distribution, community composition, and potential metabolic activity in the GON, which is an ideal test site due to its heterogeneous environment characterized by a complex hydrodynamics and terrestrial inputs of varied quantities and quality. Our study demonstrates that bacterioplankton communities in this region are highly diverse and strongly regulated by a combination of different environmental factors leading to their heterogeneous distribution, with the rare taxa contributing to a major proportion of diversity and shifts in community composition and potentially holding a key role in ecosystem functioning.


Subject(s)
Bacteria/isolation & purification , Bacteria/metabolism , Biodiversity , Seawater/microbiology , Bacteria/classification , Bacteria/genetics , Chlorophyll/metabolism , Chlorophyll A , Ecosystem , Mediterranean Sea , Phylogeny
15.
Mar Genomics ; 35: 51-61, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28566222

ABSTRACT

Seagrasses form extensive meadows in shallow coastal waters and are among the world's most productive ecosystems. Seagrasses can produce both clonally and sexually, and flowering has long been considered infrequent, but important for maintaining genetically diverse stands. Here we investigate the molecular mechanisms involved in flowering of the seagrass Posidonia oceanica, an iconic species endemic to the Mediterranean. We generated a de novo transcriptome of this non-model species for leaf, male and female flower tissue of three individuals, and present molecular evidence for genes that may be involved in the flowering process and on the reproductive biology of the species. We present evidence that suggests that P. oceanica exhibits a strategy of protogyny, where the female part of the hermaphroditic flower develops before the male part, in order to avoid self-fertilization. We found photosynthetic genes to be up-regulated in the female flower tissues, indicating that this may be capable of photosynthesis. Finally, we detected a number of interesting genes, previously known to be involved in flowering pathways responding to light and temperature cues and in pathways involved in anthocyanin and exine synthesis. This first comparative transcriptomic approach of leaf, male and female tissue provides a basis for functional genomics research on flower development in P. oceanica and other seagrass species.


Subject(s)
Life History Traits , Plant Proteins/genetics , Transcriptome , Alismatales , Flowers/genetics , Flowers/physiology , Gene Expression Profiling , Organ Specificity , Plant Leaves/genetics , Plant Leaves/physiology , Plant Proteins/metabolism , Reproduction , Spain
16.
PLoS One ; 12(4): e0175662, 2017.
Article in English | MEDLINE | ID: mdl-28441395

ABSTRACT

Copepods belonging to the Oncaeidae family are commonly and abundantly found in marine zooplankton. In the Mediterranean Sea, forty-seven oncaeid species occur, of which eleven in the Gulf of Naples. In this Gulf, several Oncaea species were morphologically analysed and described at the end of the XIX century by W. Giesbrecht. In the same area, oncaeids are being investigated over seasonal and inter-annual scales at the long-term coastal station LTER-MC. In the present work, we identified six oncaeid species using the nuclear ribosomal internal transcribed spacers (ITS rDNA) and the mitochondrial cytochrome c oxidase subunit I (mtCOI). Phylogenetic analyses based on these two genomic regions validated the sisterhood of the genera Triconia and the Oncaea sensu stricto. ITS1 and ITS2 phylogenies produced incongruent results about the position of Oncaea curta, calling for further investigations on this species. We also characterised the ITS2 region by secondary structure predictions and found that all the sequences analysed presented the distinct eukaryotic hallmarks. A Compensatory Base Change search corroborated the close relationship between O. venusta and O. curta and between O. media and O. venusta already identified by ITS phylogenies. The present results, which stem from the integration of molecular and morphological taxonomy, represent an encouraging step towards an improved knowledge of copepod biodiversity: The two complementary approaches, when applied to long-term copepod monitoring, will also help to better understanding their genetic variations and ecological niches of co-occurring species.


Subject(s)
Copepoda/genetics , DNA, Ribosomal Spacer/genetics , Phylogeny , Animals , Arthropod Proteins/genetics , Base Sequence , Electron Transport Complex IV/genetics
17.
Chemosphere ; 177: 258-265, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28314230

ABSTRACT

Diatoms produce and release polyunsaturated aldehydes (PUAs) during senescence in culture and at the end of blooms in nature and these compounds play different ecological roles, as infochemicals, allelochemicals and pheromones In order to elucidate the toxic effects of PUAs, we isolated six bacterial strains from the Mediterranean Sea during a diatom bloom and tested their tolerance to PUA in terms of growth and cell membrane properties. Based upon 16S rRNA sequencing, these bacteria were assigned to the genera Pseudomonas, Sufflavibacter, Halomonas, Vibrio, Idiomarina, and Labrenzia. Growth of these strains was reduced by 50% (EC50) at PUA concentrations ranging from 600 to 1700 µM of 2E,4E/Z-heptadienal (HEPTA), 400-800 µM of 2E, 4E/Z-octadienal (OCTA), and 70-400 µM of 2E, 4E/Z-decadienal (DECA). Two of these strains, Vibrio sp. and Halomonas, sp. were also investigated for membrane fatty acid composition in terms of adaptive modifications of their degree of saturation (ratio between saturated and unsaturated fatty acids) by GC-FID. A direct correlation between hydrophobicity and PUA toxicity was observed, and these bacteria were also found to react to PUAs by increasing the degree of saturation of their membranes fatty acids. Tested PUAs were 4-fold more toxic than the well-investigated n-alkanols, most probably due to their additional chemical aldehyde toxicity to disrupting proteins by the formation of Schiff's bases, and therefore, they act as very toxic and effective poison, probably accumulating in cytoplasmic membranes because of their high hydrophobicity.


Subject(s)
Aldehydes/chemistry , Bacteria/chemistry , Diatoms/chemistry , Fatty Acids, Unsaturated/chemistry , Esters/chemistry , Eutrophication , Geography , Hydrophobic and Hydrophilic Interactions , Lipids/chemistry , Mediterranean Sea , RNA, Ribosomal, 16S/genetics , Water Microbiology
18.
Sci Total Environ ; 562: 588-595, 2016 08 15.
Article in English | MEDLINE | ID: mdl-27110973

ABSTRACT

A Pb-resistant bacterial strain (named hereinafter Pb15) has been isolated from highly polluted marine sediments at the Sarno River mouth, Italy, using an enrichment culture to which Pb(II) 0.48mmoll(-1) were added. 16S rRNA gene sequencing (Sanger) allowed assignment of the isolate to the genus Bacillus, with Bacillus pumilus as the closest species. The isolate is resistant to Pb(II) with a minimum inhibitory concentration (MIC) of 4.8mmoll(-1) and is also resistant to Cd(II) and Mn(II) with MIC of 2.22mmoll(-1) and 18.20mmoll(-1), respectively. Inductively coupled plasma atomic emission spectrometry (ICP-AES) showed that Pb inoculated in the growth medium is absorbed by the bacterial cells at removal efficiencies of 31.02% and 28.21% in the presence of 0.48mmoll(-1) or 1.20mmoll(-1) Pb(II), respectively. Strain Pb15 forms a brown and compact biofilm when grown in presence of Pb(II). Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray Spectroscopy (SEM-EDS) confirm that the biofilm contains Pb, suggesting an active biosorption of this metal by the bacterial cells, sequestering 14% of inoculated Pb as evidenced by microscopic analyses. Altogether, these observations support evidence that strain Pb15 has potentials for being used in bioremediation of its native polluted sediments, with engineering solutions to be found in order to eliminate the adsorbed Pb before replacement of sediments in situ.


Subject(s)
Bacillus/metabolism , Lead/metabolism , Water Pollutants, Chemical/metabolism , Adsorption , Bacillus/genetics , Bacteria , Biodegradation, Environmental , Biofilms , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Italy , Microscopy, Electron, Scanning , RNA, Ribosomal, 16S , Rivers/chemistry , Rivers/microbiology
19.
J Hum Genet ; 59(10): 555-61, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25142509

ABSTRACT

Telomerase and telomeric complex have been linked to a variety of disease states related to neurological dysfunction. In amyotrophic lateral sclerosis (ALS) patients, telomerase activity, as human telomerase reverse transcriptase (hTERT) expression, has not been characterized yet. Here, for the first time, we characterized telomerase and related pathway in blood sample and spinal cord from ALS patients compared with healthy controls. We found that hTERT expression level was significantly lower in ALS patients and was correlated either to p53 mRNA expression or p21 expression, pointing out the hypothesis that telomerase inhibition could be a pathogenetic contributor to neurodegeneration in ALS. As a consequence of the reduced telomerase activity, we identified shorter telomeres in leukocytes from sporadic ALS patients compared with healthy control group.


Subject(s)
Amyotrophic Lateral Sclerosis/enzymology , Telomerase/metabolism , Aged , Amyotrophic Lateral Sclerosis/genetics , Female , Gene Expression , Humans , Leukocytes/enzymology , Male , Middle Aged , Proto-Oncogene Proteins p21(ras)/genetics , Telomerase/blood , Telomerase/cerebrospinal fluid , Telomerase/genetics , Telomere/metabolism , Tumor Suppressor Protein p53/genetics
20.
Neurogenetics ; 15(4): 243-53, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25130371

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a progressive and seriously disabling adult-onset neurological disease. Ninety percent of ALS patients are sporadic cases (sALS) with no clear genetic linkage. Accumulating evidence indicates that various microRNAs (miRNAs), expressed in a spatially and temporally controlled manner in the brain, play a key role in neuronal development. In addition, microRNA dysregulation contributes to some mental disorders and neurodegeneration diseases. In our research, the expression of one selected miRNA, miR-338-3p, which previously we have found over-expressed in blood leukocytes, was studied in several different tissues from sALS patients. For the first time, we detected a specific microRNA disease-related upregulation, miR-338-3p, in blood leukocytes as well in cerebrospinal fluid, serum, and spinal cord from sALS patients. Besides, staining of in situ hybridization showed that the signals of miR-338-3p were localized in the grey matter of spinal cord tissues from sALS autopsied patients. We propose that miRNA profiles found in tissue samples from sALS patients can be relevant to understand sALS pathogenesis and lead to set up effective biomarkers for sALS early diagnosis.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , MicroRNAs/metabolism , Aged , Amyotrophic Lateral Sclerosis/blood , Amyotrophic Lateral Sclerosis/cerebrospinal fluid , Female , Humans , Male , MicroRNAs/blood , MicroRNAs/cerebrospinal fluid , Middle Aged , Neurodegenerative Diseases/metabolism , Spinal Cord/metabolism , Up-Regulation
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