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Simple Summary: High levels of biodiversity characterize the aquatic ecosystems of Albania including coastal lagoons. They are among the most biologically rich and productive environments worldwide. These ecosystems are dynamic, transitioning between land and sea, and they serve as crucial interfaces for various ecological functions and biodiversity requiring specific monitoring programs. The current study represents a pivotal contribution to understanding the biodiversity patterns in the coastal lagoons of Albania. Species data were collected from scientific literature, grey literature, and scientific project reports. These sources about the biodiversity of Albanian lagoons rely upon traditional methods based on morphological species identification. In recent years, new innovative DNA-based methods have been developed to assess aquatic biodiversity. The efficiency of these methods is related to the availability of species "DNA barcodes" in specific international databases. In this study, we focused on the analysis of the extent of records for DNA barcodes in reference libraries, for the aquatic species of Albanian coastal lagoons. Our results reveal an overall gap of 20%, which indicates the concrete possibility of using molecular methods to investigate the marine biodiversity in Albanian lagoons. Aquatic biodiversity includes a variety of unique species, their habitats, and their interactions with each other. Albania has a large hydrographic network including rivers, lakes, wetlands and coastal marine areas, contributing to a high level of aquatic biodiversity. Currently, evaluating aquatic biodiversity relies on morphological species identification methods, but DNA-based taxonomic identification could improve the monitoring and assessment of aquatic ecosystems. This study aims to evaluate the coverage of COI DNA barcodes in the reference libraries for the known aquatic animal species present in the coastal lagoons of Albania. In this study, the six most studied coastal lagoons of Albania were selected. Species data were gathered from the scientific literature and publicly available sites and studies. The collected species lists were taxonomically standardised using global public taxonomic databases like WORMS. The standardised lists were used to analyse the barcode gap of COI based on two public DNA barcode libraries: Barcode of Life Data Systems (BOLD) and NCBI GenBank. The results show that the COI DNA barcode gap in the coastal lagoons of Albania ranges from 7% (Lagoon of Patok) to 33% (Karavasta Lagoon). Fishes and Amphibia represent the groups with the lowest barcode gap (8% each), while Annelida shows the highest (47%). In conclusion, the COI gene marker for DNA-based biodiversity assessments is reliable for the coastal lagoons of Albania. [ABSTRACT FROM AUTHOR]

Non-indigenous species (NIS) introduction notoriously threatens the Mediterranean Sea. In addition, Mediterranean coastal lagoons play a crucial role as nurseries for marine species, which new NIS arrivals can threaten. Therefore, monitoring and early warning of NIS presence is essential in preserving biodiversity. An innovative technique for rapid and accurate species identification and biodiversity screening is the application of environmental DNA (eDNA) metabarcoding. In this research, different Penaeidae (Arthropoda, Crustacea, Decapoda) NIS specimens were collected from a Mediterranean coastal lagoon after an early warning about a potentially invasive NIS arising from next-generation sequencing data. DNA barcoding of the DNA extracted from tissue samples and amplified with specifically designed primer pairs led to the recognition of Penaeus aztecus in this NATURA 2000 protected ecosystem for the first time. DNA barcoding from DNA isolated from the water where the living specimens were stored further validated the possibility of identifying P. aztecus starting from eDNA. This approach demonstrated the validity of environmental DNA analysis in the early screening of potentially invasive NIS presence in Mediterranean protected areas and ecosystems. This work describes an applicative example of the efficacy in improving the biomonitoring of lagoon ecosystems using molecular tools and it represents a guideline for the validation of eDNA metabarcoding data for the presence of potentially invasive species. [ABSTRACT FROM AUTHOR]

The canalization concept (1) describes the resistance of a developmental process to phenotypic variation, regardless of genetic and environmental perturbations, owing to the existence of buffering mechanisms. Severe perturbations, which overcome such buffering mechanisms, produce altered phenotypes that can be heritable and can themselves be canalized by a genetic assimilation process. An important implication of this concept is that the buffering mechanism could be genetically controlled. Recent studies on Hsp90, a protein involved in several cellular processes and development pathways (2-5), indicate that it is a possible molecular mechanism for canalization and genetic assimilation. In both flies and plants, mutations in the Hsp90-encoding gene induce a wide range of phenotypic abnormalities, which have been interpreted as an increased sensitivity of different developmental pathways to hidden genetic variability (6,7). Thus, Hsp90 chaperone machinery may be an evolutionarily conserved buffering mechanism of phenotypic variance, which provides the genetic material for natural selection. Here we offer an additional, perhaps alternative, explanation for proposals of a concrete mechanism underlying canalization. We show that, in Drosophila, functional alterations of Hsp90 affect the Piwi-interacting RNA (piRNA; a class of germ-line-specific small RNAs) silencing mechanism leading to transposon activation and the induction of morphological mutants. This indicates that Hsp90 mutations can generate new variation by transposon-mediated 'canonical' mutagenesis., In Drosophila, primary spermatocytes of Hsp90 mutant males exhibit crystalline aggregates (8,9) (see also Fig. 1b), usually absent in wild-type testes (Fig. 1a), the formation of which is due to [...]

AUBERGINE (AUB) is a member of the PPD family of proteins. These proteins are implicated in RNA interference. In this article we demonstrate that the expression of the aub gene and protein increase in [aub.sub.sting] mutants. We used a genetic method to test whether [aub.sub.sting] overexpression could interfere with proper functioning of the process of RNA interference in somatic tissues of Drosophila melanogaster. This method is based on a transgenic line bearing a construct in which a fragment of the yellow (y) gene is cloned to form an inverted repeat (y-IR) under the control of the upstream activation sequence (UAS) of the yeast transcriptional activator GAL4. The UAS-y-IR transgene and the Act5C-GAL4 driver were brought together on chromosome 3 via recombination. In the resulting strain (Act5C-y-IR), transcriptional activation by GAL4 constitutively produces a dsRNA hairpin bearing cognate sequences to the yellow gene causing continuing degradation of y mRNA resulting in [yellow.sub.1] ([y.sub.1]) phenocopies. In this genetic background, the mutation of any factor involved in RNAi should repress degradation of y mRNA, restoring the wild-type phenotype. We employed this genetic approach to show that an increased amount of AUBERGINE interferes with the regular functioning of the somatic RNAi pathway.

The biodiversity of the Mediterranean Sea is currently threatened by the introduction of Non-Indigenous Species (NIS). Therefore, monitoring the distribution of NIS is of utmost importance to preserve the ecosystems. A promising approach for the identification of species and the assessment of biodiversity is the use of DNA barcoding, as well as DNA and eDNA metabarcoding. Currently, the main limitation in the use of genomic data for species identification is the incompleteness of the DNA barcode databases. In this research, we assessed the availability of DNA barcodes in the main reference libraries for the most updated inventory of 665 confirmed NIS in the Mediterranean Sea, with a special focus on the cytochrome oxidase I (COI) barcode and primers. The results of this study show that there are no barcodes for 33.18% of the species in question, and that 45.30% of the 382 species with COI barcode, have no primers publicly available. This highlights the importance of directing scientific efforts to fill the barcode gap of specific taxonomic groups in order to help in the effective application of the eDNA technique for investigating the occurrence and the distribution of NIS in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]