03/06/2026
New Important Research Update on SLC52A1
A new study in the Journal of Biological Chemistry has uncovered an important discovery about SLC52A1, the gene linked to Riboflavin Transporter Deficiency Type 1 (RTD1).
For years, scientists believed the SLC52 family of genes (SLC52A1, SLC52A2, and SLC52A3) had one job: transporting riboflavin (vitamin B2) through the body. This new research shows one of them does more.
A Transporter with a Double Role
Researchers discovered that SLC52A1 also transports urate, a molecule produced when the body breaks down purines.
Urate normally circulates in the blood and is removed through the kidneys and intestines. High levels can lead to conditions such as gout.
When scientists tested the other riboflavin transporters, SLC52A2 and SLC52A3, neither transported urate. This makes SLC52A1 the first riboflavin transporter ever shown to move a second molecule while still transporting riboflavin.
The study also explains the mystery on why SLC52A1 is highly concentrated in intestinal cells but barely detected in most other tissues.
• Strategic location: SLC52A1 sits on the blood facing side of intestinal cells. From here it can move riboflavin from intestinal cells into the bloodstream and also allow urate from the blood to enter the cells, where it can later be removed through the gut. On the opposite side of these cells, SLC52A3 pulls riboflavin from the gut into the cell, working together with SLC52A1 to move vitamin B2 from food into the blood.
• Bidirectional transporter: SLC52A1 works through facilitated diffusion, meaning molecules move based on concentration. This allows riboflavin to move into the blood while urate moves from the blood into intestinal cells so it can be excreted.
Why This Matters for the RTD Community
This discovery adds an important new piece to the puzzle for understanding RTD and developing future treatments.
First, it shows riboflavin transporters are more complex than previously thought, with SLC52A1 performing more than one biological role. Cure RTD is currently supporting research to determine whether SLC52A2 and SLC52A3 may also have additional functions, which could significantly influence future treatment strategies.
Second, the study highlights a key challenge in RTD research. Unlike humans, most laboratory animals break down urate using an enzyme called uricase, so they never evolved the SLC52A1 transporter. This is one reason Cure RTD focuses heavily on cell lines derived from RTD patients.
This is exactly why Cure RTD invests in research. Breakthroughs like this expand our understanding of RTD biology and bring us one step closer to better treatments and a cure for RTD.
Reference:
Yamamoto et al., 2026. SLC52A1 Is a Neofunctionalized Primate Urate Transporter Enabling Intestinal Urate Secretion. Journal of Biological Chemistry. Link to paper: https://www.sciencedirect.com/science/article/pii/S0021925826001808