Selective localization of diacylglycerol kinase (DGK)ζ in the terminal tubule cells in the submandibular glands of early postnatal mice

Abstract

The present immunohistochemical study was attempted to localize in the submandibular glands of mice at various postnatal stages a diacylglycerol kinase (DGK) isoform termed DGKζ which is characterized by a nuclear localization signal and a nuclear export signal. This attempt was based on following facts: the continuous postnatal differentiation of glandular cells in the rodent submandibular gland, the regulatory role of DGK in the activity of protein kinase C (PKC) through attenuation of diacylglycerol (DAG), and the possible involvement of PKC in various cellular activities including the saliva secretion as well as the cell differentiation. As a result, a selective localization of immunoreactivity for DGKζ was detected in terminal tubule (TT) cells which comprise a majority of the newborn acinar structure and differentiate into the intercalated duct cells and/or the acinar cells. The immunoreactivity was deposited in portions of the cytoplasm lateral and basal to the nucleus, but not in the nuclei themselves. Although the immunoreactive TT cells remained until later stages in female specimen than in male, they eventually disappeared in both sexes by young adult stages. The present finding suggests that the regulatory involvement of DGKζ in PKC functions via control of DAG is exerted in the differentiation of the TT cells. In addition, another possible involvement of DGKζ in the regulation of secretion of the TT cells as well as its functional significance of its nuclear localization in the submandibular ganglion cells was also discussed.

Expression of c-kit and Cytokeratin 5 in the Submandibular Gland after Release of Long-Term Ligation of the Main Excretory Duct in Mice

“…During the subsequent development of salivary gland tissue , terminal tubule cells become active and proliferate from birth to the age of 2 weeks. By the age of 3 weeks, the acinar portion makes up most of the mature salivary gland tissue, and the terminal portion has mostly disappeared [5, 8, 29]. Therefore, terminal tubule cells are considered to differentiate into acinar cells (i.e., show precursor cell-like characteristics) [37].…”

Knockdown of DGKZ induces apoptosis and G2/M phase arrest in human acute myeloid leukemia HL-60 cells

“…The pathogenesis of AML has been unclear and every effort to increase our understanding of AML pathogenesis is of great significance [17][18] . DGKZ is associated with a variety of malignant diseases in humans [19][20] and is also related to proliferation and apoptosis of T cells in the blood system [21][22][23] .With the popularity of precision medical advancement, stem cell technology, cell therapy technology, and the progress of new drugs, survival will greatly enhance in cancer patients. Furthermore, certain cancers may be avoided through preventive treatment, while some may even be completely cured.…”