NOV 18, 2021 6:28 AM PST

Some Gene Isoforms are Exclusively Expressed in the Brain

WRITTEN BY: Carmen Leitch

For simplicity's sake, it's easy to think of the genome as a set of instructions that cells use to create the proteins that they need. There are around 20,000 protein-coding genes in the human genome, and the expression of these genes is carefully controlled to give cells their unique identities. But the reality is of course far more complex. There are non-coding portions of the genome and various other features of DNA like the epigenome that influence gene activity, as well as all the little sequence variations that arise in individuals. There are also different versions of genes themselves. When a gene sequence is transcribed from DNA into RNA, it can be processed in different ways, or alternatively spliced, to create variations of the same protein. Alternate isoforms have been implicated in some diseases.

Image credit: Pixabay

New research has identified many gene isoforms are expressed only in the brain, and they may have different biological functions. In the central nervous system, alternative splicing is known to be common. This study used long-read sequencing to characterize full-length genes and their isoforms, outlining the various transcripts that are found in human and mouse brains at various periods in development. About half of these isoforms have not been identified before, and many have the potential to be translated into a protein. The work has been published in Cell Reports.

Thousands of new isoforms that are only expressed in the brain were identified in this study, which also confirmed "the importance of alternative splicing in the cortex, dramatically increasing transcriptional diversity and representing an important mechanism underpinning gene regulation in the brain," said lead study author Szi Kay Leung.

Human brains had a different level of isoform diversity than mouse brains, and in the cortex, the fetal brain was very different from the adult brain isoforms. Some disease-related isoforms were also found.

"We're excited to find that genes associated with three brain diseases, Alzheimer's disease, autism, and schizophrenia, are characterized by lots of new isoforms not previously described. We are now in the process of exploring how these isoforms might play a role in the onset of disease," said research leader Professor Jonathan Mill of the University of Exeter.

The research team noted that the isoform annotation data has been made publicly available here.

Sources: University of Exeter, Cell Reports

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
NOV 07, 2021
Cell & Molecular Biology
How Cells Use Messengers to Signal to One Another
NOV 07, 2021
How Cells Use Messengers to Signal to One Another
In recent years, researchers have discovered the importance of a kind of antenna that is found on most cells, a structur ...
NOV 09, 2021
Plants & Animals
It Seems a Single Molecule Can Govern Ant Behavior
NOV 09, 2021
It Seems a Single Molecule Can Govern Ant Behavior
Some people change careers, and it seems that the Harpegnathos saltator ant can do the same; worker ants can switch to q ...
DEC 01, 2021
Genetics & Genomics
Disordered Protein Interactions are Crucial Transcription Regulators
DEC 01, 2021
Disordered Protein Interactions are Crucial Transcription Regulators
Even if the genome of an organism is free of any damaging mutations, the activity of genes has to be controlled very car ...
DEC 15, 2021
Genetics & Genomics
A Method to Detect CRISPR Gene Editing in Organisms with UV Light
DEC 15, 2021
A Method to Detect CRISPR Gene Editing in Organisms with UV Light
CRISPR gene editing tools have become common in biomedical research, and scientists have been able to apply this technol ...
DEC 26, 2021
Microbiology
To Understand the Gut Microbiome, Researchers Create New Method to ID Strains
DEC 26, 2021
To Understand the Gut Microbiome, Researchers Create New Method to ID Strains
We've long known that there are bacteria in the human gut; some can be dangerous if they are ingested. But genetic and c ...
DEC 31, 2021
Genetics & Genomics
Alzheimer's Risk Gene May Impair Neuroprotective Mechanism
DEC 31, 2021
Alzheimer's Risk Gene May Impair Neuroprotective Mechanism
Our bodies have some healing and regenerative capabilities. For most of us, cuts will mend, we'll recover from mild infe ...
Loading Comments...