CHARACTERIZATION AND PHYLOGENY OF CHOLECYSTOKININ mRNAs IN WHITE SEA BREAM

• Main Authors: Scuruchi M., Nastasi G., D'ASCOLA, ANGELA, AVENOSO, Angela, CAMPO, Giuseppe Maurizio, CALATRONI, Alberto, CAMPO, Salvatore Giuseppe
• Other Authors: Scuruchi, M., D'Ascola, Angela, Avenoso, Angela, Campo, Giuseppe Maurizio, Nastasi, G., Calatroni, Alberto, Campo, Salvatore Giuseppe
• Format: Conference Object
• Language: English
• Published: 2012
• Subjects: White Sea
• Online Access: http://hdl.handle.net/11570/2471821

Background The white sea bream, Diplodus sargus (Teleostei, Sparidae), occupies a pivotal place in gastronomy and economy of the Mediterranean and in other geographic districts. There is currently little information available about the genetic characteristics of this teleosteo, therefore the knowledge of its molecular structures and functional features could be helpful to better understand the adaptive biochemical and functional mechanisms in order to optimize its farming conditions. The peptide hormone cholecystokinin (CCK), secreted by the mid-gut, plays a key role in digestive physiology of vertebrates including fishes. Diplodus Sargus CCK mRNA sequence has not been determined yet, thus the aim of this study was to characterize the nucleotide sequence of cholecystokinin mRNA and its phylogenetic tree. Metodology In order to identify CCK gene we have used the 5’ and 3’ Gene Rapid Amplification of cDNA ends method (RACE). The phylogenetic tree was built by using MCMC algorithm, inside of MrBayes software, particularly decisive for proteins of small dimensions. Results Two different full-length nucleotide sequences were identified for white sea bream CCK mRNAs (CCK-1 and CCK-2). The white seabream CCK-1 mRNA codifies a putative protein of 137 amino acids whereas the CCK-2 mRNAs codifies a putative protein of 132 amino acids. Both CCKs have the same C-terminal octapeptide site ,thus may be considered as L-CCK. The phylogenetic tree divided the CCK family into two major groups, namely the teleostean CCK-1 and CCK-2 subfamilies. Despite they are located in two different groups, the length of the branches showed that the CCK-2 has diversified more recently than the CCK-1. These results showed that the two CCKs identified could exhibit different biological functions: a their involvement in biological processes other than digestive function needs to be evaluated.