CLONING, CHARACTERIZATION AND EXPRESSION OF VITELLOGENIN GENE OF OREOCHROMIS-AUREUS (TELEOSTEI, CICHLIDAE)

  • 1 January 1990
    • journal article
    • research article
    • Vol. 20  (4) , 843-852
Abstract
CDNA synthesized from liver poly A+ RNA of estradiol-stimulated male Oreochromis aureus was ligated to PTZ-19R and transformed into Escherichia coli. TG-1 to yield 6 .times. 104 clones/.mu.g DNA, of which 6% was vitellogenin positive. Restriction maps indicate 4 possible subgroups of vitellogenin cDNA, with homology, observed by Southern hybridisation, at a fragment flanked by Pst I sites. When the amino acid sequence derived from the DNA sequence of pOA Vg 62 was aligned with that of Salmo gairdneri, Xenopus laevis, Caenorhabditis elegans and Drosophila melanogaster, homologies of 63%, 22%, 21% and 15%, respectively, were obtained. Estradiol induced a vitellogenin gene transcript of 6500 nucleotides at 6 h and reached a maximum at 72 h after stimulation.