Retroviral Vector Method for Gene Transfer in Transgenic Mice
The retroviral vector method utilizes RNA-based retroviruses to transfer genetic material into host cells, producing chimeric organisms with diverse genetic backgrounds. After up to 20 generations of inbreeding, transgenic offspring carrying the desired transgene in all cells can be achieved. The process involves infecting cleavage-stage embryos with a defective retrovirus containing the transgene, followed by implantation in foster mothers. Although this method effectively integrates transgenes into the genome, it has limitations, such as the ability to transfer only small DNA segments and the lack of necessary regulatory sequences.
Retroviral Vector Method for Gene Transfer in Transgenic Mice
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Presentation Transcript
Lecture 21 Retroviral vector method
Retroviral vector method • A retrovirus is a virus that carries its genetic material in the form of RNA rather than DNA. • as vectors to transfer genetic material into the host cell • resulting in a chimera, an organism consisting of tissues or parts of diverse genetic constitution • chimeras are inbred for as many as 20 generations until homozygous (carrying the desired transgene in every cell) transgenic offspring are born
Figure.1 Establishing transgenic mice with retroviral vectors. Cleavage-Stage embryos, usually at the eight-cell stage, are infected with a defective retrovirus carrying a transgene. Implanted females (foster mothers) give birth to transgenic pups. Matings are carried out to determine which pups have the transgene in their germ line cells. Transgenic lines can be established from these founder transgenic animals.
Retroviral vector method • Advantage: effective means of integrating the transgene into the genome of a recipient cell. • Disadvantages: • can transfer only small pieces (approximately 8 kilo bases) of DNA • lack essential adjacent sequences for regulating the expression of the transgene. • the genome of the retroviral strain (helper virus) that is needed to create large quantities of the vector DNA can be integrated into the same nucleus as the transgene
