Phenotype of the taurine transporter knockout mouse

Area of Science:

• Physiology
• Genetics
• Biochemistry

Background:

• Taurine is an abundant amino acid crucial for various physiological functions, including cell volume regulation, neuromodulation, and antioxidant defense.
• High intracellular taurine concentrations are maintained by the taurine transporter (TAUT) in the plasma membrane.
• Taurine transporter knockout mouse models (taut-/-) are valuable tools for studying taurine's roles in vivo.

Purpose of the Study:

• To investigate the physiological and pathological consequences of disrupted taurine transport using taut-/- mice.
• To elucidate the diverse roles of taurine in the development and maintenance of normal organ functions and morphology.
• To understand the mechanisms of diseases mediated by impaired taurine transport and taurine depletion.

Main Methods:

• Phenotypic characterization of taut-/- mice compared to wild-type and heterozygous controls.
• Analysis of taurine levels in various tissues (skeletal muscle, heart, brain, kidney, plasma, retina, liver).
• Assessment of body mass, exercise capacity, and age-dependent disorders in taut-/- mice.

Main Results:

• Taut-/- mice exhibit drastically reduced taurine levels across multiple organs (70-98% decrease).
• These mice show lower body mass, reduced exercise capacity, and subtle derangements in renal osmoregulation and neuroreceptor expression.
• Clinically relevant age-dependent disorders, including visual, auditory, olfactory dysfunctions, hepatitis, and liver fibrosis, were observed in taut-/- mice.

Conclusions:

• Disruption of taurine transport leads to severe taurine deficiency, impacting organ function and morphology.
• Taurine transporter deficiency results in a complex phenotype with reduced physical capacity and age-related pathologies.
• The taut-/- mouse model is instrumental in uncovering the multifaceted roles of taurine and the consequences of its impaired transport.