The eVects of the members of growth hormone family knockdown in zebraWsh development

Growth hormone (GH), prolactin (PRL), and somatolactin (SL) are members of GH/PRL superfamily. These hormones are involved in the regulation of an array of physiological processes, including growth, lactation, and osmoregulation. While recent evidence has shown the GH, PRL, and SL gene transcripts and protein products are expressed during early zebraWsh development, their functions at this time of embryogenesis remain unknown. In the current study, antisense morpholino oligonucleotide (MO) inhibition of gh, prl, and sl gene translation was used to examine the eVects of gene knockdown on hormone function in zebraWsh development. We observed that PRL, SL and SL MO treatment all aVected development. PRL MO-treated embryos showed defects in gas bladder inXation, reduced head and eye size, shorter body length and fewer melanophores than untreated controls, whereas SL and SL MO-treated embryos were only defective in gas bladder inXation, GH MO-inhibition of GH speciWc translation did not lead to any discernable morphological changes within 10 days post fertilization (dpf). The eVects of PRL knockdown were further veriWed using a second PRL morpholino antisense and by a rescue experiment with in vitro transcribed prl mRNA containing 5 nucleotide mismatch within the PRL–MO binding region. These results provide the Wrst evidence that members of the GH/PRL superfamily play a role in proper development of various structures including the head, eyes, melanophores and the gas bladder in zebraWsh. © 2006 Elsevier Inc. All rights reserved.