Involvement of RNA binding proteins AUF1 in mammary gland differentiation
- Laboratory of Animal Breeding, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657 (Japan)
The expression of many genes, such as {beta}-casein, c-myc, and cyclin D1, is altered by lactogenic hormone stimulation during mammary epithelial cell differentiation. Here, we demonstrate that post-transcriptional regulation plays an important role to establish gene expression required to initiate milk production as well as transcriptional control. AUF1 protein, a member of the AU-rich element (ARE)-binding protein family, plays a role in ARE-mRNA turnover by regulating mRNA stability and/or translational control. Cytoplasmic localization of AUF1 protein is critically linked to function. We show that as the mammary gland differentiates, AUF1 protein moves from the cytoplasm to the nucleus. Moreover, in mammary gland epithelial cells (HC11), stimulation by lactogenic hormone decreased cytoplasmic and increased nuclear AUF1 levels. Direct binding of AUF1 protein was observed on c-myc mRNA, but not {beta}-casein or cyclin D1 mRNA. AUF1 downregulation in HC11 cells increased the expression of {beta}-casein mRNA and decreased the expression of c-myc mRNA by lactogenic hormone. Conversely, overexpression of AUF1 inhibited these effects of lactogenic hormone stimulation in HC11 cells. These results suggest that AUF1 participates in mammary gland differentiation processes under the control of lactogenic hormone signals.
- OSTI ID:
- 20972095
- Journal Information:
- Experimental Cell Research, Vol. 313, Issue 13; Other Information: DOI: 10.1016/j.yexcr.2007.04.017; PII: S0014-4827(07)00201-7; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0014-4827
- Country of Publication:
- United States
- Language:
- English
Similar Records
Extracellular matrix and hormones transcriptionally regulate bovine. beta. -casein 5 prime sequences in stably transfected mouse mammary cells
Suppression of mammary epithelial cell differentiation by the helix-loop-helix protein Id-1