The work carried out this year represents a continuation and extension of earlier studies on the role of carbohydrates in biological systems. Two separate areas are covered in this report. (a) The previously described findings on the hormonal regulation of sialylation in rat thyroid cells have been examined in human thyroglobulin isolated from patients with Graves disease and from patients exhibiting endemic goiter. In contrast to normal controls or material from endemic goiters, the thyroglubin recovered from patients with Graves disease was characterized by severe hypersialylation and aberrant localization of the sialic acid residues within the carbohydrate core. (b) Techniques designed to isolate and characterize individual nuclear protein fractions have revealed the presence of enzymatically degradable glycogen in the pore- lamina fraction of the nucleus and the presence of one or more complex glycoproteins within the nuclear matrix.
