We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
INTEGRA BIOSCIENCES AG

Download Mobile App




MicroRNAs Play a Critical Role in B Cell Maturation

By Gerald M. Slutzky, PhD
Posted on 07 Dec 2016
Print article
Image: A scanning electron microscopic (SEM) image of a single human lymphocyte (Photo courtesy of Wikimedia Commons).
Image: A scanning electron microscopic (SEM) image of a single human lymphocyte (Photo courtesy of Wikimedia Commons).
A recent paper highlighted the important role of microRNAs in the maturation of the immune system's B lymphocytes (B cells).

MicroRNAs (miRNAs) are a small noncoding family of 19- to 25-nucleotide RNAs that regulate gene expression by targeting mRNAs in a sequence specific manner, inducing translational repression or mRNA degradation, depending on the degree of complement between miRNAs and their targets. Many miRNAs are conserved in sequence between distantly related organisms, suggesting that these molecules participate in essential processes. In fact, miRNAs have been shown to be involved in the regulation of gene expression during development, cell proliferation, apoptosis, glucose metabolism, stress resistance, and cancer.

B cell development is a tightly regulated process dependent on sequential rearrangements of the genetic loci that encode the immunoglobulin antigen receptor. To better understand the role of miRNAs in the orchestration of B cell development, investigators at the Technion-Israel Institute of Technology (Haifa, Israel) eliminated all miRNAs at the earliest stage of B cell development by conditionally targeting the enzymes critical for miRNA synthsesis in early B cell precursors.

The investigators reported in the November 22, 2016, issue of the journal Cell Reports that absence of any one of these enzymes led to a block at the pro-B cell to pre-B cell transition due to increased apoptosis and a failure of pre-B cells to proliferate. Further analysis revealed that miRNAs were critical for the regulation of the PTEN-AKT-FOXO1 molecular pathway that controlled Rag expression during B cell development. Regulation of PI3K (Phosphoinositide 3-kinase) signaling by miRNAs was essential for keeping Rag expression in check.

The recombination-activating genes (RAGs) encode enzymes that play an important role in the rearrangement and recombination of the genes of immunoglobulin and T cell receptor molecules. There are two recombination-activating gene products known as RAG-1 and RAG-2, whose cellular expression is restricted to lymphocytes during their developmental stages. RAG-1 and RAG-2 are essential to the generation of mature B and T lymphocytes.

“Appropriate PI3K activity determines the positive and the negative selection of B cells,” explained contributing author Dr. Doron Melamed, professor of immunology at the Technion-Israel Institute of Technology. “Activation of PI3K is balanced by another biochemical process in the pathway called Pten. While the extent of the “cross talk” between PI3K and Pten has been unclear, our work has demonstrated that a microRNA (miRNA), which regulates gene expression, can sensitize the process for B cells turning cancerous and also enable them to evade cell death.”

Related Links:
Technion-Israel Institute of Technology

Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Specimen Collection & Transport
Anti-Cyclic Citrullinated Peptide Test
GPP-100 Anti-CCP Kit
New
Gold Member
Plasma Control
Plasma Control Level 1

Print article

Channels

Clinical Chemistry

view channel
Image: Reaching speeds up to 6,000 RPM, this centrifuge forms the basis for a new type of inexpensive, POC biomedical test (Photo courtesy of Duke University)

POC Biomedical Test Spins Water Droplet Using Sound Waves for Cancer Detection

Exosomes, tiny cellular bioparticles carrying a specific set of proteins, lipids, and genetic materials, play a crucial role in cell communication and hold promise for non-invasive diagnostics.... Read more

Molecular Diagnostics

view channel
Image: The cobas Malaria test is the first FDA-approved molecular test to screen U.S. blood donors for malaria (Photo courtesy of Roche)

First FDA-Approved Molecular Test to Screen Blood Donors for Malaria Could Improve Patient Safety

Malaria, a serious illness that often leads to death, is spread by a specific mosquito species that infect humans with a parasite. Other transmission modes include blood transfusions, organ transplants,... Read more

Hematology

view channel
Image: The low-cost portable device rapidly identifies chemotherapy patients at risk of sepsis (Photo courtesy of 52North Health)

POC Finger-Prick Blood Test Determines Risk of Neutropenic Sepsis in Patients Undergoing Chemotherapy

Neutropenia, a decrease in neutrophils (a type of white blood cell crucial for fighting infections), is a frequent side effect of certain cancer treatments. This condition elevates the risk of infections,... Read more

Pathology

view channel
Image: The medical office procedure detects the key biomarker in Parkinson’s and related neurodegenerative diseases (Photo courtesy of BIDMC)

Simple Skin Biopsy Test Detects Parkinson’s and Related Neurodegenerative Diseases

Parkinson's disease and a group of related neurodegenerative disorders known as synucleinopathies impact millions globally. These conditions, including Parkinson’s disease (PD), dementia with Lewy bodies... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.