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Analysis of Protein-protein Interactions and Co-localization Between Components of Gap, Tight, and Adherens Junctions in Murine Mammary Glands
11:31

Analysis of Protein-protein Interactions and Co-localization Between Components of Gap, Tight, and Adherens Junctions in Murine Mammary Glands

Published on: May 30, 2017

Nuclear localization and function of polypeptide ligands and their receptors: a new paradigm for hormone specificity

Charles V Clevenger1

  • 1Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA. clevengc@mail.med.upenn.edu

Breast Cancer Research : BCR
|June 24, 2003
PubMed

Insights

Polypeptide hormones and growth factors can enter the nucleus, directly regulating gene expression. This nuclear function offers new therapeutic targets for mammary cell regulation.

Area of Science:

  • Cellular and Molecular Biology
  • Endocrinology
  • Genetics

Background:

  • Hormone and growth factor signaling in mammary cells was traditionally attributed to cell surface receptor-mediated pathways.
  • The precise mechanisms governing the specific cellular responses to these stimuli were not fully elucidated.

Purpose of the Study:

  • To investigate the potential role of polypeptide ligands and their receptors beyond cell surface signaling.
  • To explore the direct impact of these molecules within the cell nucleus on gene regulation.

Main Methods:

  • Analysis of intracellular localization of polypeptide ligands and their receptors.
  • Assessment of nuclear translocation and its correlation with gene expression changes.
  • Identification of specific transcription factors and gene loci regulated by intranuclear complexes.

Main Results:

  • Evidence demonstrates that polypeptide ligands and/or their receptors are transported into the nucleus.
  • These nuclear complexes directly regulate the expression of specific transcription factors.
  • Nuclear translocation influences the expression of particular gene loci, impacting mammary cell function.

Conclusions:

  • Mammary cell responses to polypeptide hormones/growth factors involve direct nuclear actions of ligands and/or receptors.
  • Intranuclear signaling complexes represent a novel mechanism of gene regulation.
  • These findings identify potential new targets for pharmacological interventions in mammary cell-related conditions.

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