The ability of asialo-thyroglobulin to bind the thyroid RHL-1 subunit of the asialoglycoprotein receptor has been investigated. Ligand blot assays show that the recombinant carbohydrate recognition domain of the thyroid RHL-1 subunit specifically interacts with rat desialated thyroglobulin. Moreover, RT-PCR and Western blot assays show that TSH deprivation decreases RHL-1 expression in PC C13 thyroid differentiated cells whereas insulin deprivation does not have any effect. The simultaneous absence of both TSH and insulin dramatically decreases the level of RHL-1 expression.