Analyses of expressed sequence tags from an agarophyte, Gracilaria changii (Gracilariales, Rhodophyta)

Red seaweeds of the genus Gracilaria are agarophytes that produce more than 60% of the world's agar supply. Despite the importance of this genus in agar production, the potential of Gracilaria as a candidate for genomic research has been almost unexplored. In this study, a total of 8,088 expressed sequence tags (ESTs) were generated from Gracilaria changii, and clustered into 4922 tentative unique genes (TUGs), of which approximately 35% showed significant matches (bit scores greater than 50 and E-values less than 10(-5)) to other genes in the databases. Among the TUGs that have significant similarity to the genes in the databases are ESTs corresponding to diverse functional groups such as metabolism, transcription, signalling, translation, transportation, protein folding, sorting, destination and degradation, cell division, cellular processes, replication and repair, cell structure, and miscellaneous. cDNAs involved in diverse metabolic pathways were identified among the EST collection. The presence and frequency of the transcripts allow us to survey the transcriptomic activities of this tropical agarophyte.