Related Experiment Video
Updated: Feb 7, 2026
An In-vitro Preparation of Isolated Enteric Neurons and Glia from the Myenteric Plexus of the Adult Mouse
Published on: August 7, 2013
Expression of RAD21 immunoreactivity in myenteric neurons of the human and mouse small intestine
F Bianco1,2, S T Eisenman3,4, M G Colmenares Aguilar3,4
1Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy.
Background:
RAD21 is a double-strand-break repair protein and component of the cohesin complex with key roles in cellular functions. A RAD21 loss-of-function mutation was found in cases of chronic intestinal pseudo-obstruction (CIPO) with associated enteric neuronal loss. Analysis of RAD21 expression in the enteric nervous system is lacking, thus we aimed to characterize RAD21 immunoreactivity (IR) in myenteric ganglia.
Methods:
Double labeling immunofluorescence in mouse and human jejunum was used to determine colocalization of RAD21 with HuC/D, PGP9.5, neuronal nitric oxide synthase (nNOS), neuropeptide Y (NPY), choline acetyl transferase (ChAT), Kit, platelet-derived growth factor receptor-α (PDGFRα), and glial fibrillary acid protein (GFAP) IRs.
Results:
A subset of PGP9.5- and HuC/D-IR neuronal cell bodies and nerve fibers in the myenteric plexus of human and mouse small intestine also displayed cytoplasmic RAD21-IR Cytoplasmic RAD21-IR was found in 43% of HuC/D-IR neurons in adult and neonatal mice but did not colocalize with nNOS. A subset of ChAT-positive neurons had cytoplasmic RAD21-IR Punctate RAD21-IR was restricted to the nucleus in most cell types consistent with labeling of the cohesin complex. Cytoplasmic RAD21-IR was not detected in interstitial cells of Cajal, fibroblast-like cells or glia. Subsets of neurons in primary culture exhibited cytoplasmic RAD21-IR Suppression of RAD21 expression by shRNA knockdown abolished RAD21-IR in cultured neurons.
Conclusions:
Our data showing cytoplasmic RAD21 expression in enteric neurons provide a basis toward understanding how mutations of this gene may contribute to altered neuronal function/survival thus leading to gut-motor abnormalities.
Insights
RAD21 protein, crucial for DNA repair and cohesin complex function, is present in enteric neurons. This finding may explain how RAD21 mutations contribute to gut-motor disorders like CIPO.
Area of Science:
- Gastroenterology
- Molecular Biology
- Neuroscience
Background:
- RAD21 is a DNA repair protein and cohesin complex component vital for cellular functions.
- RAD21 loss-of-function mutations are linked to chronic intestinal pseudo-obstruction (CIPO) and enteric neuronal loss.
- Expression of RAD21 in the enteric nervous system (ENS) remains largely uncharacterized.
Purpose of the Study:
- To investigate RAD21 immunoreactivity (IR) in the myenteric ganglia of the enteric nervous system.
- To characterize the cellular localization of RAD21 in enteric neurons and associated cells.
Main Methods:
- Immunofluorescence double labeling was performed on mouse and human jejunum.
- RAD21 colocalization was assessed with neuronal markers (HuC/D, PGP9.5, nNOS, NPY, ChAT) and other cell markers (Kit, PDGFRα, GFAP).
- RAD21 expression was also examined in cultured enteric neurons with and without shRNA knockdown.
Main Results:
- Cytoplasmic RAD21 immunoreactivity (IR) was observed in a subset of myenteric neurons and nerve fibers in both human and mouse small intestine.
- RAD21-IR neurons were positive for HuC/D and a subset were positive for ChAT, but not nNOS.
- RAD21-IR was nuclear in most cell types but cytoplasmic in a subset of neurons; it was absent in interstitial cells of Cajal, glia, and fibroblasts.
Conclusions:
- Cytoplasmic RAD21 expression in enteric neurons provides a potential mechanism linking RAD21 mutations to gut-motor abnormalities.
- This study establishes a foundation for understanding the role of RAD21 in enteric neuronal health and disease.
- Further research into RAD21's function in the ENS may reveal therapeutic targets for CIPO and related disorders.
Related Concept Videos
01:23Anatomy of the Intestines
Small Intestines
The small intestine is an ~7 meter-long tube with an inner diameter of just 2.5 cm. Since most nutrients are absorbed here, the inner lining of the...
01:58Cell Specific Gene Expression
01:42What is Gene Expression?
Gene expression is the process in which DNA directs the synthesis of functional products, that is, proteins. Cells can regulate gene expression at various stages. It allows organisms to generate different cell types and enables cells to adapt to internal and external factors.
Genetic Information Flows from DNA to RNA to Protein
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is made up of nucleotides and proteins consist of amino...
01:15Small Intestine
The small intestine is divided into three main sections - the duodenum, jejunum, and ileum. The duodenum, approximately 25 cm long, is nearest the stomach. It acts as a 'mixing bowl,' where chyme (partially digested food) blends with digestive enzymes from the pancreas and liver. The duodenum's unique...
01:09Large Intestine
The ileocecal sphincter, a mucous membrane fold, guards the opening from the ileum to the large intestine. This valve permits material from the small intestine to pass into the large intestine. Attached to the ileocecal valve is the cecum. This small pouch, approximately 6 cm long, has a twisted, coiled tube known as...
01:26Histology of the Large Intestine
The innermost mucosa layer comprises simple columnar epithelium, lamina propria, and muscularis mucosae. This layer is primarily populated with absorptive cells, tasked with water absorption, and goblet cells, responsible for secreting mucus to...