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Seagrasses exhibit vital ecological roles in the marine environment. Nevertheless, the genomic resources available for seagrasses are still scarce. In the present study, the transcriptome of Cymodocea nodosa was sequenced with a view to study the molecular mechanisms underlying abiotic stress responses. The sequenced transcriptome for the species was near-complete and a high percentage of the transcripts was computationally annotated. An experimental simulation of marine plant exposure to extreme temperature (34°C), salinity (50psu) and their combination was conducted. A dynamic transcriptome 24h response (short-term) from stress initialization was recorded. The most noteworthy alteration in gene expression was observed in heat-stressed plants. Transcripts associated with development, photosynthesis, osmotic balance and stress-response were differentially expressed, under the set experimental conditions. Results indicate a potential negative interaction of heat and osmotic stress on seagrasses transcriptome.

-Myxozoans are metazoan parasites which are highly pathogenic in commercially important fish, particularly in aquaculture. Enteromyxosis is an economically significant disease caused by the myxosporean parasite Enteromyxum leei. Presently, early diagnosis of enteromyxosis in sharpsnout seabream was achieved by monitoring fish on a time-scale scheduled basis in combination with a validated molecular diagnostic technique. Two different successive fish batches of a commercial fish farm were monitored starting from the first month of on-growing in sea cages until fish reached commercial size. Fish weight and water temperature differentially ranged between them. E. leei detection was performed both by classical microscopic observation of fresh smears and by quantitative polymerase chain reaction (qPCR) while prevalence, mean intensity and mortality rate were calculated. In total, 520 fish were screened; 320 from the first batch and 200 from the second one. Parasitosis illustrated a seasonal occurrence pattern (spring and summer). When qPCR was used as a diagnostic method, enteromyxosis was diagnosed earlier with more increased prevalence compared to the microscopic observation. In this case, the parasite was detected at the lowest water temperature that has ever been recorded (14.7• C), during the first month of on-growing in sea cages. The twofactor combination of water temperature and fish weight proved to be the most significant factor that could determine the emergence and development of parasitosis and smaller fish proved to be more susceptible. Mortality was influenced by both prevalence and intensity of parasitosis. An earlier diagnosis and identification of all developmental stages of the parasite throughout its life cycle was verified with qPCR, significantly before any outbreak occurred. The latter could become a key diagnostic tool for the control of enteromyxosis, allowing stakeholders and fish farmers to adopt all necessary precautionary measures minimizing economic loss in sharpsnout seabream intensive farming.

Nowadays, molecular biology has definitely become an interdisciplinary science. Toward the study of the functions and the interactions of the biological molecules, such as nucleic acids and proteins, computer science and engineering, along with chemistry and statistics, are routinely engaged. In molecular biology, techniques and methods are constantly developed, and new techniques emerge. Next-generation sequencing and bioinformatics have become the cornerstones of molecular biology. The developing technologies have led to a decrease of the cost per molecular unit analyzed, but at the cost of computer integration and intensification. Many research methods require a reference nucleic acid sequence. Considering the necessary integration of sequencing data and methodology, combining the "omics" approaches can help to elucidate more complex null hypotheses. Here, data processing basics, with an emphasis to commonly used techniques, are summarized. The knowledge gaps are discussed as well as further prospective for integrating nextgeneration sequencing data.