Related Experiment Video
Updated: Aug 5, 2026

The Organoid Reconstitution Assay (ORA) for the Functional Analysis of Intestinal Stem and Niche Cells
Published on: November 20, 2017
The quest for a human ori
1International Centre for Genetic Engineering and Biotechnology, Trieste, Italy.
Abstract:
Attempts at identifying DNA replication origins in human cells have been performed with a variety of molecular genetic and biochemical approaches, with often controversial results. The combination of bromodeoxyuridine labelling, immunopurification of newly synthesized labelled DNA, measurement of the relative abundance of markers in this DNA by quantitative competitive PCR, has allowed the identification within 450 bp of the start-site of DNA replication located at the human lamin B2 gene. The origin is located near the non-transcribed spacer between two highly transcribed genes and shows evidence of a number of specific protein-DNA interactions, the most prominent of which disappears when the cells are differentiated into a non-proliferating state.
Related Concept Videos
The Fossil Record
The Tree of Life - Bacteria, Archaea, Eukaryotes
Eukaryotic Evolution
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
Requirements for Human Life
Oxygen
Atmospheric air is only about 20 percent oxygen, but that oxygen is a key component of the chemical reactions that keep the body alive, including the reactions that produce ATP. Brain cells are susceptible to a lack of oxygen because they require a...
Personal Identity
Origin of Cellular Life

