Mice deficient in G(olf) are anosmic

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• Olfactory signal transduction is a complex process involving G protein-coupled receptors.
• The G alpha subunit, G(olf), is known to be expressed in olfactory sensory neurons.

Purpose of the Study:

• To investigate the specific role of G(olf) in olfactory signal transduction using gene targeting.
• To elucidate the broader physiological and behavioral functions of G(olf).

Main Methods:

• Gene targeting was employed to create mice homozygous for a null mutation in the G(olf) gene.
• Electrophysiological recordings were used to assess olfactory sensory neuron responses.
• Behavioral analyses were conducted to evaluate nursing, maternal, and general activity levels.

Main Results:

• Mice with a G(olf) null mutation exhibited a significant reduction in electrophysiological responses to various odors.
• Despite altered olfactory responses, the topographic mapping of sensory projections to the olfactory bulb remained intact.
• Homozygous mutant mice displayed severe nursing deficits, high early mortality, and hyperactivity in survivors, with females showing inadequate maternal behaviors.

Conclusions:

• G(olf) is essential for olfactory signal transduction, mediating responses to a wide range of odors.
• The G(olf) protein plays a critical role in essential behaviors such as nursing and maternal care.
• Beyond olfaction, G(olf) may function as a key signaling molecule in central brain regions, influencing behavior.