Characterization of ecotropic murine leukemia viruses in SJL/J mice

Area of Science:

• Virology
• Genetics
• Immunology

Background:

• Murine leukemia viruses (MuLV) are retroviruses that can cause leukemia in mice.
• SJL/J mice possess two ecotropic MuLV loci, Emv-9 and Emv-10, which are relevant for studying viral integration and expression.
• Understanding the genetic basis of MuLV production is crucial for controlling retroviral infections.

Purpose of the Study:

• To determine the inducibility of infectious ecotropic murine leukemia virus (MuLV) from mice carrying either the Emv-9 or Emv-10 locus.
• To investigate the molecular basis for differences in MuLV production between Emv-9 and Emv-10.

Main Methods:

• Backcross mice segregating for Emv-9 and Emv-10 were utilized.
• Tail tissues were subjected to induction protocols to assess spontaneous and inducible MuLV production.
• Restriction enzyme analysis was performed on Emv-9 to identify structural alterations.

Main Results:

• No spontaneous MuLV production was detected in any of the tested mice.
• Tail tissue from mice carrying Emv-10 was inducible for ecotropic MuLV production.
• Tail tissue from mice carrying Emv-9 was not inducible for ecotropic MuLV production.
• Preliminary analysis suggested a deletion within the polymerase region of Emv-9.

Conclusions:

• The Emv-10 locus is capable of producing infectious ecotropic MuLV upon induction.
• The Emv-9 locus appears to be defective in producing infectious ecotropic MuLV, likely due to a deletion in its polymerase region.
• These findings highlight the importance of specific viral gene regions in determining MuLV infectivity and production.