What is SRSF1 (or Serine/Arginine-Rich Splicing Factor 1)?

Table of Contents

• In a Nutshell
• What is SRSF1?
• What is RNA splicing?
• How does SRSF1 work?
• What else does SRSF1 do?
• Why does the amount of SRSF1 matter?
• What is SRSF1’s role in cancer?
• What does SRSF1 do in healthy tissues?
• What does SRSF1 have to do with aging?
• Does SRSF1 reverse aging?
• Could SRSF1 become a treatment?
• What we still don’t know
• Frequently Asked Questions
• Sources

In a Nutshell

• SRSF1 is an RNA-binding protein. Its main job is helping cells edit RNA before they use it to make proteins.
• It is a major regulator of RNA splicing. SRSF1 helps decide which sections of an RNA message are kept and which are removed.
• One gene can make several protein versions. SRSF1 helps control this process, called alternative splicing.
• SRSF1 does more than splice RNA. It also affects how RNA moves through the cell, how proteins are made, how some folded RNA structures are opened, and how cells protect their DNA.
• Cells need the right amount. Too little SRSF1 can damage normal tissues. Too much can help drive cancer in some settings. [5] [7]
• A 2026 study added aging to the picture. Raising SRSF1 made old human cells look younger by several molecular measures and was linked to slower frailty and longer life in a small mouse study. This has not been shown in people. [14]

What is SRSF1?

SRSF1 is the name of both a human gene and the protein that gene makes.

The official gene name is serine and arginine rich splicing factor 1. The gene sits on chromosome 17, in a region called 17q22. Older research papers may use other names, including SF2, ASF, SF2/ASF, SFRS1, or SRp30a. NCBI lists the current human gene as SRSF1, Gene ID 6426. [1]

The human SRSF1 protein is 248 amino acids long. It belongs to a family called the SR proteins. The name comes from two amino acids that appear many times in part of the protein: serine, written as S, and arginine, written as R. [2]

SRSF1 is not limited to one organ. Cells throughout the body use it because almost every cell must process RNA correctly before it can make the proteins it needs.

What is RNA splicing?

To understand SRSF1, it helps to think of a gene as a set of instructions that first gets copied into a rough draft.

That first RNA copy often contains useful sections mixed with sections that must be removed. The useful sections are called exons. The sections between them are called introns.

Before the cell can use the RNA, a large molecular machine called the spliceosome cuts out the introns and joins the exons together. The finished message is called messenger RNA, or mRNA. The cell can then read that mRNA to make a protein.

But cells do not always join the exons in the same way.

A cell may keep one exon in the brain but leave it out in the liver. It may choose one ending in a young cell and another ending in an older cell. This process is called alternative splicing.

Alternative splicing allows one gene to make several different RNA messages and, in many cases, several different forms of a protein. Those protein forms can have different jobs and can sometimes even work against one another.

SRSF1 helps the cell make these choices. Research has found that it can affect the processing of more than 1,500 messenger RNAs, although the exact targets vary from one type of cell to another. [4]

How does SRSF1 work?

SRSF1 works mainly by binding to RNA and helping other splicing proteins gather in the right place.

The protein has two regions called RNA-recognition motifs. These act like gripping surfaces that can recognize and attach to RNA. SRSF1 also has a region rich in serine and arginine, known as the RS domain. That part helps SRSF1 interact with other proteins involved in splicing. [2] [4]

The cell can also change SRSF1 by adding small phosphate groups to it. This process, called phosphorylation, can affect where SRSF1 goes inside the cell and which proteins it works with.

SRSF1 does not do the actual cutting and joining of RNA by itself. Instead, it helps the spliceosome find the right places to work and helps guide the machinery through several steps.

A 2024 study showed how central that role may be. Researchers mapped proteins that came close to SRSF1 inside living cells. They found many known splicing proteins and confirmed that SRSF1 directly interacts with DDX23, an enzyme that helps the spliceosome change shape before it becomes active. The work was published in the Proceedings of the National Academy of Sciences. [3]

What else does SRSF1 do?

SRSF1 was discovered through its role in splicing, but it has turned out to have several other jobs.

It can move between the cell nucleus, where DNA is stored and most splicing takes place, and the cytoplasm, where many proteins are made. This lets SRSF1 take part in several stages of a messenger RNA’s life.

Studies have linked SRSF1 to moving mRNA out of the nucleus, controlling how efficiently some RNAs are turned into proteins, and helping cells remove faulty RNA messages. [13]

Researchers have also found that SRSF1 can deal with unusually folded RNA.

Some RNA sequences rich in the chemical base guanine can fold into strong four-sided structures called G-quadruplexes. These folds can act like roadblocks. If one sits in the wrong place, the cell’s protein-making machinery may have trouble reading the RNA.

In 2024, researchers reported that SRSF1 can bind to these RNA G-quadruplexes and help unfold them. In one experiment, SRSF1 opened a G-quadruplex in an RNA called ARPC2, making it easier for the cell to use that message. The findings appeared in Nucleic Acids Research. [4]

SRSF1 also appears to help protect DNA.

As a cell copies DNA into RNA, the new RNA can sometimes stick back onto the DNA that made it. This creates a structure called an R-loop. Some R-loops are normal and useful. Too many, however, can leave DNA exposed and raise the risk of damage.

Experiments in mouse liver cells showed that removing SRSF1 caused R-loops to build up. DNA damage increased, normal gene activity fell, and the cells became sick and died. [7]

Why does the amount of SRSF1 matter?

Cells seem to need SRSF1 within a fairly narrow range.

Too little can be harmful because cells lose an important part of their RNA-processing system. In animal studies, removing SRSF1 from particular tissues can damage the liver, heart, reproductive system, and other organs.

Too much can also be harmful. If SRSF1 becomes unusually abundant, it can change the splicing of many genes at once. Some of those genes control cell growth, survival, and metabolism. A shift in the wrong direction can help a cell become cancerous. [5]

This is why SRSF1 is better understood as a regulator that must be kept in balance. It is not simply a “good” protein or a “bad” protein.

What is SRSF1’s role in cancer?

SRSF1 became especially important in cancer research after scientists discovered that raising its level could help turn normal cells into cancer-like cells.

In 2007, researchers led by Adrian Krainer reported that the gene then widely called SF2/ASF was present at unusually high levels in several human tumors. Raising SRSF1 in laboratory-grown cells caused those cells to change in ways associated with cancer, and the altered cells formed tumors in mice. The researchers described SRSF1 as a proto-oncogene, a normal gene that can help drive cancer when its activity becomes too high. The study appeared in Nature Structural & Molecular Biology. [5]

Since then, high or poorly controlled SRSF1 activity has been linked to cancers of the breast, lung, prostate, colon, brain, pancreas, and blood, among others. [13]

One reason is that cancer cells depend heavily on RNA processing. A change in splicing can make a growth-promoting protein instead of a growth-limiting one. It can make a cell harder to kill. It can change how the cell uses energy or responds to treatment.

Pancreatic cancer offers a clear example. In a 2023 study, researchers found increased SRSF1 in inflamed pancreatic tissue, early precancerous growths, and pancreatic cancer. Raising SRSF1 in experimental models made inflammation worse and helped mutant KRAS, one of the main drivers of pancreatic cancer, push cells toward cancer. Part of the effect came from changes in an RNA message called IL1R1. [8]

Yet SRSF1 can also trigger a defense against cancer.

Researchers reported in 2013 that excess SRSF1 can help stabilize p53, one of the body’s most important tumor-suppressing proteins. Higher p53 can push a threatened cell into senescence, a state in which the cell remains alive but stops dividing. [6]

That may sound contradictory, but it makes biological sense. A protein that drives abnormal growth can also set off the cell’s emergency brakes. Cancer can develop when later changes disable those brakes.

What does SRSF1 do in healthy tissues?

Because SRSF1 controls so many RNA messages, its effects show up in many parts of the body.

Brain and development. The SRSF1 gene lies inside a section of chromosome 17 that can be missing in people with a rare condition called 17q22 deletion syndrome. A 2026 study reviewed people with overlapping deletions and found strong evidence that losing one copy of SRSF1 contributes to developmental problems. Among 15 reported people whose deletion included SRSF1, 13 had intellectual disability or broad developmental delay. Many also had differences in facial development. Because these chromosome deletions can remove several genes at once, SRSF1 may not explain every feature by itself. [12]

Liver. SRSF1 also helps liver cells protect their DNA. When researchers removed SRSF1 from liver cells in mice, harmful R-loops built up and DNA damage rose. The animals developed inflammation, scarring, abnormal fat metabolism, and liver disease that resembled metabolic dysfunction-associated steatohepatitis. [7]

Male fertility. Making sperm requires pairs of chromosomes to find one another and line up with great precision. In a 2023 mouse study, removing SRSF1 from germ cells disrupted this process. The mice could not make sperm normally. Researchers traced part of the problem to faulty splicing of several genes needed to pair and organize chromosomes during meiosis. [9]

Lung scarring. SRSF1 has also been studied in pulmonary fibrosis, a disease in which scar tissue builds up in the lungs. Experiments in mice and human cells suggest that a long RNA molecule called DACH1 can bind SRSF1 and reduce a chain of signals that promotes scarring. Raising SRSF1 weakened that protective effect. This remains experimental research, not a proven treatment in people. [10]

Blood-vessel repair. SRSF1 may help the body grow new blood vessels after a loss of blood flow. In a 2025 study, SRSF1 increased in the cells lining blood vessels after oxygen levels fell. Mice that lacked SRSF1 in these cells recovered blood flow less well after an artery was blocked. Raising SRSF1 had the opposite effect and improved new vessel growth. [11]

The lesson is not that SRSF1 has one master function that explains all these conditions. Its basic job is controlling RNA. Different cells use different sets of genes, so changing SRSF1 can produce very different results in the liver, brain, blood vessels, reproductive organs, or a tumor.

What does SRSF1 have to do with aging?

A major new finding in 2026 pushed SRSF1 into aging research.

Scientists wanted to find genes that could make old cells behave more like young cells without wiping away the cells’ identity. That is important because some powerful forms of cellular reprogramming can make cells younger but also push them toward a stem-cell-like state, which could be dangerous inside the body.

In a study published in Nature Aging on October 14, 2026, researchers built a system that estimated the age of human skin cells from patterns of gene activity. They then tested genes to see whether increasing any of them could shift old cells toward a younger pattern. [14]

SRSF1 stood out.

When the researchers raised SRSF1 in older human fibroblasts, the cells’ patterns of gene activity looked younger. The cells still behaved like fibroblasts, the connective-tissue cells from which they started. They did not appear to turn into stem cells. [14]

In one experiment, researchers raised SRSF1 for five days and then switched it off for two days. Even after it was switched off, the treated cells had gene-activity patterns that the team’s model rated about 11 years younger than those of untreated cells. [14]

The researchers also looked beyond the age score.

Cells with more SRSF1 showed fewer signs of senescence. They showed less activity in an inflammatory pathway called NF-kappaB. They also showed changes suggesting that their systems for maintaining and recycling proteins were under less stress. Some tests based on chemical marks on DNA also moved in a younger direction, although the results were not the same in every cell line. [14]

The team then tested SRSF1 in animals.

In aged mice, they used a modified virus to deliver extra Srsf1. Most of the added gene activity ended up in the liver rather than throughout the body.

The treated mice had a median lifespan of 886 days, compared with 778 days for the control mice. That was an increase of about 14%. The researchers also estimated that frailty built up about 44% more slowly in the SRSF1 group. [14]

Those results are notable, but they come with major limits.

The mouse experiment was small, with only nine or ten animals in each group. Most of the added SRSF1 reached the liver. The result had not yet been independently repeated when the paper appeared. Some of the researchers are also inventors on a patent application involving SRSF1 and aging, and two reported an ownership interest in a company developing treatments for age-related disease. Independent testing will therefore be especially important. [14]

Does SRSF1 reverse aging?

There is no evidence that SRSF1 reverses aging in people.

The 2026 study goes further than simply showing that SRSF1 levels change with age. The researchers deliberately raised SRSF1 and then saw changes in old cells and aged animals. That suggests SRSF1 may play a real role in some parts of the aging process. [14]

But “aging” is not one measurement.

A cell can score younger on a gene-expression test without becoming young in every biological sense. A mouse can live longer without proving that the same treatment will help people. And a treatment that helps one tissue may harm another.

SRSF1 presents an especially difficult problem because scientists already know that too much of it can promote cancer-related changes in some cells. [5]

That means any future anti-aging use would have to answer a crucial question: can researchers capture the helpful effects of SRSF1 without increasing the risk of abnormal cell growth?

Could SRSF1 become a treatment?

Possibly, but a treatment would probably need to be much more precise than simply raising or lowering SRSF1 throughout the body.

Blocking SRSF1 everywhere could be dangerous because healthy cells need it. The liver studies show that losing SRSF1 can quickly damage cells and their DNA. [7]

Raising it everywhere could cause a different problem. SRSF1 can change the processing of a large number of RNAs, including some that control cancer-related pathways.

A safer strategy might target one tissue, one disease, or one part of the SRSF1 pathway. A treatment might raise SRSF1 only for a short time. It might change how SRSF1 works with one partner protein. Or it might correct one harmful splicing event without changing SRSF1 itself.

The blood-vessel research shows what that narrower approach could look like. Scientists found that SRSF1 changed the splicing of a gene called ATF3 in endothelial cells after a loss of blood flow. That set off a chain of signals that helped new blood vessels grow. Rather than treating SRSF1 as a universal drug target, researchers could study that pathway specifically in damaged blood vessels. [11]

What we still don’t know

SRSF1 has been studied for more than 30 years, but important questions remain.

Scientists still cannot look at every RNA sequence and reliably predict what SRSF1 will do to it. The result can depend on where SRSF1 binds, how much of it is present, which other proteins are nearby, how the RNA is folded, and what type of cell is involved.

The G-quadruplex discovery also raises a broader question. How much of SRSF1’s effect comes from choosing splice sites, and how much comes from physically changing the shape of RNA? [4]

Researchers also need better human genetic evidence. The findings from 17q22 deletion syndrome strongly suggest that losing one copy of SRSF1 can harm development, but those chromosome deletions often remove neighboring genes too. Finding more people with changes limited mainly to SRSF1 would help scientists define its specific effects. [12]

The aging work creates perhaps the biggest new set of questions. Can other laboratories reproduce the result? Will larger groups of mice show the same lifespan effect? Which tissues matter most? How long does SRSF1 need to be raised? Does long-term treatment increase cancer risk? And can scientists separate the effects that appear helpful in aging from the effects that can help tumors grow? [14]

Frequently Asked Questions

What does SRSF1 stand for?

SRSF1 stands for serine and arginine rich splicing factor 1. The protein belongs to a family rich in the amino acids serine and arginine. Older research may call it SF2, ASF, SF2/ASF, SFRS1, or SRp30a. [1]

Is SRSF1 a gene or a protein?

Both. SRSF1 is the human gene. The gene contains the instructions for making the SRSF1 protein.

Where is the SRSF1 gene?

The human SRSF1 gene is on chromosome 17, in a region called 17q22. [1]

What is SRSF1’s main job?

Its best-known job is helping control RNA splicing. It binds RNA and helps cells decide which parts of a new RNA message should be kept when the final messenger RNA is assembled.

What is alternative splicing?

Alternative splicing lets a cell build different RNA messages from the same gene. By keeping or removing different sections, one gene can sometimes produce several forms of a protein.

Is SRSF1 part of the spliceosome?

SRSF1 works closely with the spliceosome, but it is better described as a splicing regulator than as one of the core parts that performs the RNA-cutting reactions. It helps the machinery recognize the right RNA sites and move through the splicing process. [3]

Is SRSF1 an oncogene?

SRSF1 is often called a proto-oncogene. Normal cells need it, but unusually high SRSF1 can promote cancer-related changes. Its effects are complicated because excess SRSF1 can also turn on p53 and stop some cells from dividing. [5] [6]

Can too little SRSF1 cause problems?

Yes. Animal studies show that cells can become badly damaged when SRSF1 is lost. Human genetic evidence also suggests that losing one copy of the gene can contribute to developmental problems. [7] [12]

Does SRSF1 make cells younger?

A 2026 study found that raising SRSF1 made old human cells look younger by several molecular measures. The same study found slower frailty and longer median life in a small group of aged mice. No study has shown that SRSF1 treatment makes people younger or extends human life. [14]

Can people take SRSF1 as an anti-aging treatment?

No approved anti-aging treatment based on SRSF1 exists. The research is experimental, and scientists would need to understand safety, dosing, tissue effects, and cancer risk before testing such an approach in people.

Last reviewed: October 15, 2026. This article will be updated if the SRSF1 aging results are independently repeated, larger animal studies clarify the benefits and risks, human genetic studies better define SRSF1-related developmental disorders, or SRSF1-based treatments enter clinical testing.

Sources

1. National Center for Biotechnology Information. SRSF1 serine and arginine rich splicing factor 1 [Homo sapiens]. NCBI Gene, Gene ID 6426.
2. UniProtKB Q07955: Serine/arginine-rich splicing factor 1. UniProt Consortium.
3. Segovia, D., Adams, D. W., Hoffman, N., et al. “SRSF1 interactome determined by proximity labeling reveals direct interaction with spliceosomal RNA helicase DDX23.” Proceedings of the National Academy of Sciences 121, e2322974121 (2024). DOI: 10.1073/pnas.2322974121.
4. De Silva, N. I. U., Lehman, N., Fargason, T., et al. “Unearthing a novel function of SRSF1 in binding and unfolding of RNA G-quadruplexes.” Nucleic Acids Research 52, 4676-4690 (2024). DOI: 10.1093/nar/gkae213.
5. Karni, R., de Stanchina, E., Lowe, S. W., Sinha, R., Mu, D. & Krainer, A. R. “The gene encoding the splicing factor SF2/ASF is a proto-oncogene.” Nature Structural & Molecular Biology 14, 185-193 (2007). DOI: 10.1038/nsmb1209.
6. Fregoso, O. I., Das, S., Akerman, M. & Krainer, A. R. “Splicing-factor oncoprotein SRSF1 stabilizes p53 via RPL5 and induces cellular senescence.” Molecular Cell 50, 56-66 (2013). DOI: 10.1016/j.molcel.2013.02.001.
7. Arif, W., Mathur, B., Saikali, M. F., et al. “Splicing factor SRSF1 deficiency in the liver triggers NASH-like pathology and cell death.” Nature Communications 14, 551 (2023). DOI: 10.1038/s41467-023-35932-3.
8. Wan, L., et al. “Splicing Factor SRSF1 Promotes Pancreatitis and KRASG12D-Mediated Pancreatic Cancer.” Cancer Discovery 13, 1678-1695 (2023). DOI: 10.1158/2159-8290.CD-22-1013.
9. Sun, L., Chen, J., Ye, R., et al. “SRSF1 is crucial for male meiosis through alternative splicing during homologous pairing and synapsis in mice.” Science Bulletin 68, 1100-1104 (2023). DOI: 10.1016/j.scib.2023.04.030.
10. Sun, J., Jin, T., Niu, Z., et al. “LncRNA DACH1 protects against pulmonary fibrosis by binding to SRSF1 to suppress CTNNB1 accumulation.” Acta Pharmaceutica Sinica B 12, 3602-3617 (2022). DOI: 10.1016/j.apsb.2022.04.006.
11. Zhu, W., Xie, N., Li, Z., et al. “Endothelial SRSF1 Promotes Ischemia-Induced Angiogenesis via ATF3-KLF2-S1PR1 Pathway.” Circulation Research 137, 1498-1521 (2025). DOI: 10.1161/CIRCRESAHA.125.326391.
12. Wu, Y., Gao, C., Chen, Z., Liu, F., Yuan, J. & Cheng, W. “SRSF1 haploinsufficiency drives the neurodevelopmental phenotype of the 17q22 deletion syndrome.” Frontiers in Medicine 13, 1750790 (2026). DOI: 10.3389/fmed.2026.1750790.
13. Lo Giudice, A., Asmundo, M. G., Broggi, G., et al. “The Clinical Role of SRSF1 Expression in Cancer: A Review of the Current Literature.” Applied Sciences 12, 2268 (2022). DOI: 10.3390/app12052268.
14. Plesa, A. M., Jung, S., Wang, H. H., et al. “Transcriptomic reprogramming screen identifies SRSF1 as a regulator of aging.” Nature Aging 6, 2057-2073 (2026). Published October 14, 2026. DOI: 10.1038/s43587-026-01234-8.