Related Experiment Video
Updated: Jun 3, 2026

Characterization at the Molecular Level using Robust Biochemical Approaches of a New Kinase Protein
Published on: June 30, 2019
PU.1 is a major transcriptional activator of the tumour suppressor gene LIMD1
Daniel E Foxler1, Victoria James, Samuel J Shelton
1School of Biomedical Sciences, University of Nottingham Medical School, Nottingham, UK.
Abstract:
LIMD1 is a tumour suppressor gene (TSG) down regulated in ∼80% of lung cancers with loss also demonstrated in breast and head and neck squamous cell carcinomas. LIMD1 is also a candidate TSG in childhood acute lymphoblastic leukaemia. Mechanistically, LIMD1 interacts with pRB, repressing E2F-driven transcription as well as being a critical component of microRNA-mediated gene silencing. In this study we show a CpG island within the LIMD1 promoter contains a conserved binding motif for the transcription factor PU.1. Mutation of the PU.1 consensus reduced promoter driven transcription by 90%. ChIP and EMSA analysis demonstrated that PU.1 specifically binds to the LIMD1 promoter. siRNA depletion of PU.1 significantly reduced endogenous LIMD1 expression, demonstrating that PU.1 is a major transcriptional activator of LIMD1.
Related Concept Videos
Abnormal Proliferation
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein.
Master Transcription Regulators
Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
Negative Regulator Molecules
lncRNA - Long Non-coding RNAs
