Direct stimulation of immediate-early genes by intranuclear insulin in trypsin-treated H35 hepatoma cells.
نویسندگان
چکیده
H35 hepatoma cells were treated with trypsin to abolish insulin binding and insulin-stimulated receptor kinase activity. Insulin was, however, internalized by fluid-phase endocytosis in trypsin-treated cells. Furthermore, nuclear accumulation of insulin was similar in control and trypsin-treated hepatoma cells. Northern blot analysis revealed insulin increased g33 and c-fos mRNA concentrations identically in control and trypsin-treated cells but had no effect on beta 2-microglobulin mRNA. Actinomycin D treatment prior to or after insulin addition demonstrated that insulin increased gene transcription and had no effect on mRNA degradation. These studies suggest that the accumulation of intact insulin in cell nuclei may be directly involved in the increased transcription of immediate-early genes.
منابع مشابه
Insulin- and phorbol ester-stimulated phosphorylation of ribosomal protein S6.
The relative abilities of insulin and the phorbol ester tumor promoter 12-O-tetradecanoyl phorbol 13-acetate (TPA) to lead to the phosphorylation of ribosomal protein S6 in vivo were compared in a Reuber H35 hepatoma cell line shown previously to be highly responsive to these agents. In quiescent (serum-starved) cultures of H35 cells incubated with 32Pi, both insulin (10(-7) M) and TPA (1.6 X 1...
متن کاملRat hepatoma cell variants resistant to insulin-diphtheria toxin A fragment conjugates. Genetic evidence for the separate pathways for insulin receptor-mediated mitogenic and hormonal stimulation.
The rat hepatoma H35 cells in serum-free medium produce tyrosine aminotransferase (TAT) and initiate DNA synthesis and cell division upon exposure to 10(-9)-10(-10) M insulin. This insulin-dependent hormonal and mitogenic stimulation is through the insulin receptors and not through the receptors for insulin-like growth factor type I. We have isolated genetic variants of H35 cells which are resi...
متن کاملGene Expression under F8 Promoter Driving In Mouse Hepatoma Cells: A Step towards Gene Therapy of Hemophilia
Background and Objectives: Significant progress has been made in treatment of hemophilia. Ex-vivo gene therapy is going popular due to the capability of this method in using isogenic cells for genetic manipulation and reintroducing them into same host after proliferation. Most gene therapy techniques use viral vectors, which usually harbor a strong and non-specific promoter (e...
متن کاملInsulin stimulates glyceraldehyde-3-phosphate dehydrogenase gene expression through cis-acting DNA sequences.
Glyceraldehyde-3-phosphate dehydrogenase [GAPDH; D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12] mRNA levels are induced by physiologic concentrations of insulin in cultured 3T3-F442A adipocyte and H35 hepatoma cell lines. To examine the mechanism by which insulin regulates GAPDH mRNA levels in these two insulin-sensitive tissues, we have isolated a functional h...
متن کاملNovel delayed-early and highly insulin-induced growth response genes. Identification of HRS, a potential regulator of alternative pre-mRNA splicing.
We have identified 41 novel and many previously known growth response genes induced in regenerating liver and insulin-treated Reuber H35 cells, a rat hepatoma cell line that grows in response to physiologic concentrations of insulin and retains some properties of regenerating liver. Although many genes are expressed similarly in the two systems, there are important differences in the kinetics o...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 89 20 شماره
صفحات -
تاریخ انتشار 1992