Transgenic Research

, Volume 9, Issue 6, pp 417–427 | Cite as

Copy Number Related Transgene Expression and Mosaic Somatic Expression in Hemizygous and Homozygous Transgenic Tilapia (Oreochromis Niloticus)

  • M. Azizur Rahman
  • Gyu-Lin Hwang
  • Shaharudin Abdul Razak
  • Frédéric Sohm
  • Norman Maclean

Abstract

Three lines of transgenic tilapia (Oreochromisniloticus) fish were generated with a constructcontaining a lacZ reporter gene spliced to a 4.7 kb 5′ regulatory region of a carp beta actin gene. All these three lines contain different copy numbers oftransgenes and the levels of lacZ expressionwere found to be related to transgene copy number.Mosaic patterns of somatic lacZ expression wereobserved in these three lines which differed between linesbut were consistent within a line. We also observedthat expression of the reporter gene in homozygoustransgenic fish was approximately two-fold greater thanin the hemizygous transgenics. Analysis of expressionof the reporter gene on a tissue-to-tissue basisdemonstrated that lacZ expression of thereporter gene in stably transformed fish occured withvariable intensity in different organs and tissues andwas also sometimes variable in different cells of thesame tissue in G1and G2 generations of the transgenic lines.

β-galactosidase mosaic expression transgenic fish 

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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • M. Azizur Rahman
    • 1
  • Gyu-Lin Hwang
    • 1
  • Shaharudin Abdul Razak
    • 1
  • Frédéric Sohm
    • 1
  • Norman Maclean
    • 2
  1. 1.Division of Cell Sciences, School of Biological SciencesUniversity of SouthamptonSouthamptonUnited Kingdom
  2. 2.Division of Cell Sciences, School of Biological SciencesUniversity of SouthamptonSouthamptonUnited Kingdom

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