High levels of DNA polymerase β mRNA corresponding with the high activity in Graves' thyroid tissue.

Abstract

INTRODUCTION:

High DNA polymerase β activity has been observed in the thyroid tissue of patients with Graves' disease (Nagasaka et al. in Metabolism 37:1051-1054, 1988). This fact aroused our interest in whether the alteration of DNA polymerase β activity depends on DNA polymerase β (DNA poly β) mRNA levels, which may be modulated by thyroid-stimulating hormone (TSH) or thyroid-stimulating substances, i.e. TSH receptor antibody (TRAb).

RESULT:

Addition of TSH or TRAb to primary cultures of Graves' disease thyroid cells for 4 h led to no increase in DNA poly β mRNA levels. In contrast, thyroid hormone synthesizing enzyme, peroxidase, mRNA levels increased fivefold after coculture with TSH and TRAb, even though DNA poly β activity and mRNA levels are already significantly higher in Graves' disease thyroid tissues, compared with normal thyroid tissue.

DISCUSSION:

These results indicate that DNA poly β expression in Graves' disease thyroid cells may be maximally activated or plateau in response to thyroid-stimulating immunoglobulins, or that the activation of to poly β expression may occur via pathways other than the G protein and cyclic AMP system.

• Authors: N Hayakawa, Y Sato, A Nagasaka, Y Mano, T Nagasaka, A Nakai, K Iwase, S Yoshida
• Journal: Journal of endocrinological investigation (J Endocrinol Invest) Vol. 40 Issue 4 Pg. 385-389 (Apr 2017) ISSN: 1720-8386 [Electronic] Italy
• PMID: 27848228 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Autoantigens
• Immunoglobulins, Thyroid-Stimulating
• Iron-Binding Proteins
• RNA, Messenger
• Receptors, Thyrotropin
• Thyroid Hormones
• Thyrotropin
• TPO protein, human
• Iodide Peroxidase
• DNA Polymerase beta

Topics

• Autoantigens (genetics)
• Blotting, Northern
• Cells, Cultured
• DNA Polymerase beta (genetics)
• Graves Disease (enzymology, genetics, pathology)
• Humans
• Immunoglobulins, Thyroid-Stimulating (pharmacology)
• Iodide Peroxidase (genetics)
• Iron-Binding Proteins (genetics)
• RNA, Messenger (genetics)
• Receptors, Thyrotropin (immunology)
• Thyroid Gland (enzymology, pathology)
• Thyroid Hormones (metabolism)
• Thyrotropin (pharmacology)