Identification of Dll1 (Delta1) target genes during mouse embryogenesis using differential expression profiling

Area of Science:

• Developmental Biology
• Molecular Biology
• Genetics

Background:

• The Notch signaling pathway plays crucial roles in mammalian embryogenesis, particularly in patterning and differentiation.
• It is essential for the development of paraxial mesoderm and the neural tube.

Purpose of the Study:

• To identify genes and proteins differentially regulated in Dll1 mutant embryos using comprehensive expression profiling.
• To uncover novel targets and downstream effects of Notch signaling during embryonic development.

Main Methods:

• DNA-chip expression profiling to identify regulated transcripts.
• 2D-gel electrophoresis and peptide mass fingerprinting to identify differentially expressed proteins.
• Whole-mount in situ hybridization and immunoblots for validation.

Main Results:

• Identified 47 regulated transcripts and 40 differentially expressed proteins in Dll1 mutant embryos.
• Many identified genes were not previously linked to Notch signaling.
• Expression patterns of identified genes were altered in key embryonic tissues, including the presomitic mesoderm, somites, and neural tube.
• Six proteasome subunits were found to be down-regulated in Dll1 mutant embryos.

Conclusions:

• This study provides a substantial resource of novel genes and proteins regulated by Notch signaling.
• The findings offer new avenues for investigating the complex roles of Notch in embryonic development.
• The identification of proteasome subunits suggests a link between Notch signaling and protein degradation pathways.