Functional expression study of igf2 antisense transcript in mouse.

Area of Science:

• Developmental biology
• Genetics
• Molecular biology

Background:

• The role of the insulin-like growth factor antisense gene (Igf2as) in mammalian development is not fully understood.
• Previous studies linked intrauterine growth restriction in a specific mouse model to Igf2 transcription, but the involvement of Igf2as was unclear.

Purpose of the Study:

• To investigate the expression patterns of Igf2as in various mouse tissues during development.
• To determine if Igf2as interacts with or regulates Igf2 transcripts.
• To reassess the phenotype of the ΔDMR1-U2 knockout mouse model.

Main Methods:

• Analysis of Igf2as gene expression in different mouse tissues (fetal, newborn, adult liver, muscle, placenta, brain).
• Investigation of Igf2as expression in differentiating C2C12 cells.
• Examination of Igf2 expression in ΔDMR1-U2 knockout mouse placentas lacking Igf2as transcription.

Main Results:

• Igf2as expression was high in fetal and newborn liver and muscle, and also detected in placenta and brain.
• No consistent evidence of interaction between Igf2 and Igf2as transcripts was found.
• Igf2 expression in knockout placentas lacking Igf2as was comparable to wild-type, indicating Igf2as does not regulate Igf2.

Conclusions:

• Igf2as plays a role in early mouse development and placental function.
• Igf2as does not regulate Igf2 sense transcripts.
• The phenotype of the ΔDMR1-U2 knockout mouse should be reconsidered due to the functional Igf2as gene.