Proteomic analysis during larval development and metamorphosis of the spionid polychaete Pseudopolydora vexillosa

Unlike the significant changes found during barnacle metamorphosis, proteomes of competent P. vexillosa larvae were more similar to those of their juveniles. Pre-competent larvae had significantly fewer protein spots (384 spots), while both competent larvae and juveniles expressed about 660 protein spots each. Proteins up-regulated during competence identified by MALDI-TOF/TOF analysis included a molecular chaperon (calreticulin), a signal transduction regulator (tyrosin activation protein), and a tissue-remodeling enzyme (metallopeptidase).This was the first time to study the protein expression patterns during the metamorphosis of a marine polychaete and to compare the proteomes of marine invertebrates that have different levels of morphological changes during metamorphosis. The findings provide promising initial steps towards the development of a proteome database for marine invertebrate metamorphosis, thus deciphering the possible mechanisms underlying larval metamorphosis in non-model marine organisms.Marine invertebrates have a biphasic life cycle that includes a pelagic larval stage that is morphologically distinct from the adult form [1]. Their larvae typically metamorphose into juveniles or adults simultaneously with or directly following settlement out of the water column; they will subsequently colonize and structure the benthic communities [2]. Marine industries also target settlement and metamorphosis processes when developing methods to eliminate species that deteriorate infrastructure and commercial resources by biofouling man-made surfaces or interfering with aquaculture [3,4].In general, common features of marine invertebrate metamorphosis include tissue remodeling and differentiation that are under hormonal or transcriptional control and are mediated by differential gene and protein expressions [5]. However, the specific mechanisms of metamorphosis vary from species to species [6,7]. For example, since the metamorphic transitions in different taxa m