Teleost fishes have evolved impressive strategies to maximize reproductive fitness. One strategy is to change sex, which involves the "re-modeling" of sexual dimorphic brain regions that control sex-specific reproductive behaviors. The teleost brain shows tremendous plasticity and, unlike mammals, synthesizes high levels of aromatase to control this transformation. Halichoeres melanurus or tail-spot wrasse is a species of wrasse endemic to the western Pacific from Japan to Samoa and south to the Great Barrier Reef. Larval fish first develop into smaller females, and transition into larger males. Thus, this species is sexually dimorphic and phenotypic sex is discernable, although little is known about the transition state during female to male sex change. We employed SMRT sequencing (PacBio IsoSeq) to obtain a reference transcriptome for gene mapping and de novo sequence assembly for H. melanurus. Primary cell cultures for radial glia cells (RGCs) were isolated from male wrasse, and subsequently treated with 17beta-estradiol at 1 µM for 24 hours in culture to identify estrogen-responsive transcripts in RGCs. This is important because radial glial cells express aromatase (AroB), the enzyme that converts testosterone (T) into estradiol (E2) and one, which is considered to be one of the master regulators for sex change. E2 altered the expression of 55 genes in the RGCs and down-regulated spectrin alpha, non-erythrocytic and 1 3-phosphoinositide dependent protein kinase 1b while up-regulating ATPase H+ transporting V1 subunit C1 and calcium binding protein 39. Our transcriptome network analysis revealed that E2 induced gene networks associated with plasticity of neurons (e.g. synaptic transmission, nervous system activation, and axonal guidance) suggesting that E2 mediates glial derived synaptic patterning in the CNS. Other major processes that were increased with E2 treatment in the wrasse RGCs were those associated with immune system development and function, as well as the inflammatory and innate immune response. These investigations are expected to shed novel insight into the neuroplasticity of sex in teleost fishes.