Characterization of growth-related genes in the south-western Atlantic pink shrimp Farfantepenaeus paulensis (Pérez-Farfante 1967) through a modified DDRT-PCR protocol

Abstract

An exploratory methodology has been used toidentifygenes related to growth of the shrimp Farfan-tepenaeus paulensis(Pe¤rez-Farfante, 1967). Six hun-dred postlarvae, with an average ( SD) initialweight of 0.022 g ( 0.008), were reared for 60 daysin salinity 30gL 1. In the end, the 15 heaviest(41.2 g) andthe15 lightest (o0.6g)animalswerefro-zen in liquid nitrogen. A modi¢ed di¡erential display reverse transcription-polymerase chain reactiontechnique was used to generate expression pro¢lesfor all individuals. The resulting cDNA from reverse transcription were ampli¢ed by pairing 31 arbitrary primers with a reverse primer anchored to the cDNAtails. From the comparison between the expressionpro¢les of the organisms in the two size classes, dif-ferences could be pinpointed. Bands of interest werecollected, puri¢ed, clonedand sequenced. Despite the relatively small number of primers used, the metho-dology allowed the identi¢cation of three genes, not described previously for the investigated species and possibly related to growth. These partial sequences are likely to belong to genes that code for myosin heavy chain, cyclophilin and haemocyanin as revealed through an amino acid similarity search conducted using the BLASTPon-line tool.