JAN 17, 2016 6:31 AM PST

Host microRNAs Shape the Microbiome

WRITTEN BY: Kerry Evans
Researchers at Brigham and Women’s Hospital and Harvard Medical School identified a new mechanism that mammals use to manage their gut microbes.

A number of factors shape the host microbiome, including diet, disease, and genetics.  Weiner and colleagues found that microRNAs (miRNAs) produced by intestinal epithelial cells are capable of regulating bacterial growth.

miRNAs are non-coding RNAs, roughly 18-23 nucleotides in length.  The pre-miRNAs are processed in the cytoplasm by an enzyme called dicer.  The miRNAs base pair to complementary sequences of mRNA and this interaction silences gene expression through various mechanisms.  The human genome probably encodes around 1,000 miRNAs that regulate roughly 60% of the genome.
 
miRNAs effectively silence gene expression.

According to study author Howard Weiner, “since gut microbes play an important role in host metabolism and immunity as well as in disease, it is important to understand the mechanisms by which the microbiota is regulated by the host and to identify ways in which to manipulate the microbiome … our findings reveal a host defense mechanism and highlight microRNAs as a strategy for manipulation of the microbiome for the health of the host”.

The group found that mice with dicer-deficient intestinal epithelial cells had trouble controlling the growth of their gut microbes and developed colitis more frequently.  This was reversed, however, when the mice were treated with wild type miRNAs.  Finally, they showed that the mouse miRNAs were capable of entering bacteria.  They added fluorescent miRNAs to fluorescent E. coli cells and observed the miRNAs entering the bacteria and interacting with their DNA.  

“Our study suggests that the ability of the host to control gut microbes likely provided organisms with an evolutionary advantage, that is, the prevention of diseases such as colitis and colorectal cancer … we are optimistic that it will one day be possible to harness this natural host defense mechanism by administering microRNAs as therapeutic compounds to improve health and treat disease", says Weiner.

Sources: Cell, Science Daily, Wikipedia
About the Author
Kerry received a doctorate in microbiology from the University of Arkansas for Medical Sciences.
You May Also Like
JUN 22, 2022
Plants & Animals
Beer Could Help Diversify Gut Microbiomes
JUN 22, 2022
Beer Could Help Diversify Gut Microbiomes
No need to cut beer out of your diet just yet if you’re looking to improve your health. According to a recent stud ...
JUN 28, 2022
Cell & Molecular Biology
Scientists Discover Viruses That Infect Archaea
JUN 28, 2022
Scientists Discover Viruses That Infect Archaea
Recent research has suggested that all eukaryotic life is descended from an Asgard archaea
JUL 01, 2022
Immunology
This Day in Science History - Edward Jenner & The Smallpox Vaccine
JUL 01, 2022
This Day in Science History - Edward Jenner & The Smallpox Vaccine
Smallpox is caused by the variola virus, which can be spread though infectious droplets that are exhaled as people talk, ...
JUL 04, 2022
Genetics & Genomics
Scientists Urge Study of Bacteria in Melting Glaciers
JUL 04, 2022
Scientists Urge Study of Bacteria in Melting Glaciers
Globally, temperatures are on the rise. Between the years of 2009 and 2019, glaciers around the world lost an average of ...
AUG 01, 2022
Cell & Molecular Biology
Representation in STEM Matters
AUG 01, 2022
Representation in STEM Matters
Amid the increasing conversation regarding diversity and inclusion, it is important to understand the role they both pla ...
SEP 19, 2022
Microbiology
Labroots 2022 Microbiology Virtual Week Poster Winner: Dr. Emmanuel Ogbonna
SEP 19, 2022
Labroots 2022 Microbiology Virtual Week Poster Winner: Dr. Emmanuel Ogbonna
Labroots’ virtual events are a fantastic way to network and learn about the work of other researchers in your fiel ...
Loading Comments...