Complete cDNAs for CDC42 from chicken cochlea and mouse liver

Area of Science:

• Molecular Biology
• Genetics
• Cell Signaling

Background:

• CDC42 is a small GTP-binding protein within the ras superfamily, crucial for signal transduction.
• Small GTP-binding proteins share a conserved GTP-binding domain, indicating functional relatedness.

Purpose of the Study:

• To isolate and characterize CDC42 cDNAs from different species.
• To investigate the expression pattern of the mouse CDC42 gene.
• To identify and map CDC42-like genes in the mouse genome.

Main Methods:

• cDNA isolation and sequencing from chick cochlea and mouse liver.
• Amino acid sequence comparison between avian, mouse, and human CDC42 proteins.
• Northern blot analysis to determine gene expression across mouse tissues.
• Southern blot analysis and genetic mapping to locate CDC42-like genes.

Main Results:

• Two full-length CDC42 cDNAs were isolated (chick and mouse), both encoding a 191-amino acid protein.
• Avian and mouse CDC42 proteins showed high similarity to the human placental isoform.
• The mouse CDC42 gene is expressed in all examined tissues.
• At least three CDC42-like genes (Cdc42l1, Cdc42l2, Cdc42l3) were identified in the mouse genome, with specific chromosomal localizations.

Conclusions:

• CDC42 exhibits conserved structure and function across species, with variations potentially influencing specific roles.
• The widespread expression of mouse CDC42 suggests a fundamental cellular role.
• The presence of multiple CDC42-like genes indicates a complex regulatory network and potential for specialized functions within the mouse genome.