Meet the newest member of the biomolecular family

A new type of biomolecule is discovered by a group of scientists from Boston’s Children Hospital that might be present in all living things on Earth and could pave the way in discovering biochemical pathways still unknown to this day.

For biochemistry, there are four known main building blocks that make up every life on Earth: carbohydrates, lipids fats, nucleic acids (RNA and DNA), and proteins. These biomolecules could then interact with each other forming subtypes such as combining sugar and lipids to form blood cells.

Glycan is a chain of sugar molecules which could then attach to proteins and fats in a process called glycosylation. These glycolipids and glycoproteins are involved in fundamental biological processes such as reproduction to immune responses.

Published from scientific journal Cell in May 2021, the research entitled “Small RNAs are modified with N-glycans and displayed on the surface of living cells” found out how glycans can also attach to non-coding RNA. The team of researchers led by biochemist Ryan Flynn worked this through by tagging glycol molecules with sialic acid then extracting the RNA, resulting in purified RNA with a sialic acid-labeled sugar coating.

Conventionally, RNA is only found within the cell’s fluids or nucleus meanwhile glycans are found outside the cell beside its membrane, so interactions between the two came off as a novel discovery.

"This is exciting because it means that glycoRNAs can participate directly in cell-to-cell communication. That was previously thought to be off-limits for RNAs, which had not been thought to play a role on the cell surface," Flynn said.

This glycoRNA is found to be present in humans, mice, hamsters, and zebrafish, suggesting vital biological functions that are preserved by life and evolution.

Stanford biochemist Carolyn Bertozzi lauded the group for the stunning discovery of an entirely new class of biomolecules.

"It's really a bombshell because the discovery suggests that there are biomolecular pathways in the cell that are completely unknown to us," she added.