Regulation of acyl coenzyme A reductase by a heat-stable cytosolic protein during preputial gland development

A low-molecular-weight protein located in the cytosol of mouse preputial glands has been shown to stimulate the activity of a microsomal acyl coenzyme A (CoA) reductase in the gland. This cytoplasmic protein was stable to heating and lyophilization, but was destroyed by trypsin digestion. It was able to bind palmitoyl-CoA and gel elution behavior indicated it had a molecular weight of 10,000–12,000. The level of this stimulatory cytosolic protein and the activity of acyl-CoA reductase were shown to correlate with differentiation of the preputial gland during development of puberty in male mice; the acyl-CoA reductase activity first appeared at 4 weeks of age and increased dramatically up to 6 weeks of age. By 8 weeks, when sexual maturity was attained, the reductase activity decreased to that level found in mature male mice. The cytosol from the preputial glands of the youngest mice (3 weeks) contained sufficient heat-stable acyl-CoA binding protein to stimulate acyl-CoA reduction; however, the 3-week-old preputial gland microsomes had little or no acyl-CoA reductase activity. As the animal matured, the stimulatory capacity in the heat-treated cytosol increased, reaching a maximum at 6 weeks; by 8 weeks, the stimulatory capacity of the soluble fraction had decreased to that found in mature male mouse. Results of this study suggest that the concentration of acyl-CoA, cytoplasmic acyl-CoA binding protein, and acyl-CoA reductase activity regulate the level of fatty alcohols in vivo and that the reductase activity and binding protein have similar patterns of development during puberty.