Related Experiment Video
Updated: Jul 11, 2026

Modified Yeast-Two-Hybrid System to Identify Proteins Interacting with the Growth Factor Progranulin
Published on: January 17, 2012
Epidermal growth factor increases the interaction between nucleolin and heterogeneous nuclear ribonucleoprotein
Pin-Tse Lee1, Pao-Chi Liao, Wen-Chang Chang
1Department of Pharmacology and Institute of Basic Medical Sciences, College of Medicine, and Center for Gene Regulation and Signal Transduction Research, National Cheng Kung University, Tainan, Taiwan 701.
Abstract:
Gastrin, a gastrointestinal hormone responsible for gastric acid secretion, has been confirmed as a growth factor for gastrointestinal tract malignancies. High expression of gastrin mRNA was observed in pancreatic and colorectal cancer; however, the mechanism is unclear. Epidermal growth factor (EGF) was found to increase gastrin mRNA stability, indicating mRNA turnover regulation mechanism is involved in the control of gastrin mRNA expression. Using biotin-labeled RNA probe pull-down assay combined with mass spectrometry analysis, we identified the heterogeneous nuclear ribonucleoprotein K (hnRNP K) and poly(C) binding protein 1 (PCBP1) bound with the C-rich region in gastrin mRNA 3' untranslated region. Nucleolin bound with the AGCCCU motif and interacted with hnRNP K were also demonstrated. Under EGF treatment, we observed the amount of nucleolin interacting with hnRNP K and gastrin mRNA increased. Using small interfering RNA technology to define their functional roles, we found hnRNP K, PCBP1, and nucleolin were all responsible for stabilizing gastrin mRNA. Moreover, nucleolin plays a crucial role in mediating the increased gastrin mRNA stability induced by EGF signaling. Besides, we also observed hnRNP K/PCBP1 complex bound with the C-rich region in the gastrin mRNA increased nucleolin binding with gastrin mRNA. Finally, a novel binding model was proposed.
Related Concept Videos
Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
Regulation of Nuclear Protein Sorting
GPCRs Regulate Adenylyl Cylase Activity
Two...
The Nucleolus
Mitogens and the Cell Cycle
Abnormal Proliferation