Sfide della vita ad ambiente estremo. I pesci dell'Antartide

Conferenza Universit\ue0 della terza Et\ue0 (UniTE) Universit\ue0 di Genov

Life in a Frozen Ocean. Vita in un mare di ghiaccio.

In recent years, outreach and communication of polar sciences have been acknowledged as priorities for the Antarctic scientific community. One of the basic need to improve the effectiveness of knowledge transfer and dissemination is the availability of educational products being at the same time engaging and scientifically rigorous. The documentary movie \u201cLife in a Frozec Ocean\u201d (Director R. Palozzi, Erebus Production, Italy, 2014, 27 min) is the core of the educational project \u201cCommunicate the polar science. Fishes of Antarctica\u201d (Italian National Programme for Antarctic Research, PNRA), aiming at bringing cutting-edge science to large public, students, teachers and society, and to help heighten public awareness of the importance of polar ecosystems and polar research. The plot revolves around the Antarctic fish that are subjects and players, leading the spectator to the exploration of the challenging environment that they dominate, the Antarctic marine coastal waters. In the video, marine biologists are followed in their sampling through the sea-ice cover in Terra Nova Bay and divers disclose to the viewer an extraordinary underwater scenario. Several fish species, living in coastal waters of the Ross Sea, are shown in their habitat for the first time. Particular focus is given to the Antarctic silverfish whose nursery area has been included in the recently established ASPA n\ub0 173 (Cape Washington & Silverfish Bay). In this documentary, some of the amazing adaptations and peculiar biological features of the Antarctic fish are expressed simply. In addition, fish are the starting point to shine light on the complex ecological interactions characterizing the Antarctic marine ecosystems, and on the potential implications of climate changes on the marine living communities

Strategie naturali contro il freddo.

Contributo elettronico a "AulaScienze". Zanichelli http://aulascienze.scuola.zanichelli.it

Assembly of the antifreeze glycoprotein/trypsinogen-like protease genomic locus in the Antarctic toothfish Dissostichus mawsoni (Norman)

To investigate the genomic architecture underlying the quintessential adaptive phenotype, antifreeze glycoprotein (AFGP) that enables Antarctic notothenioid survival in the frigid Southern Ocean, we isolated the AFGP genomic locus from a bacterial artificial chromosome library for Dissostichus mawsoni. Through extensive shotgun sequencing of pertinent clones and sequence assembly verifications, we reconstructed the highly repetitive AFGP genomic locus. The locus comprises two haplotypes of different lengths (363.6 kbp and 467.4 kbp) containing tandem AFGP, two TLP (trypsinogen-like protease), and surprisingly three chimeric AFGP/TLP, one of which was previously hypothesized to be a TLP-to-AFGP evolutionary intermediate. The ~100 kbp haplotype length variation results from different AFGP copy number, suggesting substantial dynamism existed in the evolutionary history of the AFGP gene family. This study provided the data for fine resolution sequence analyses that would yield insight into the molecular mechanisms of notothenioid AFGP gene family evolution driven by Southern Ocean glaciation