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Station Science 101: Epigenetics Research in Space


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A growing body of research suggests a link between epigenetic mechanisms and a wide variety of illnesses and behaviors, including cancer, cardiovascular and autoimmune illnesses, and cognitive dysfunction. Epigenetics also plays a role in the changes humans and other living things experience in space.

This phenomenon has become part of studies in a wide variety of fields, including microgravity research conducted aboard the International Space Station.

So just what is epigenetics? According to a paper from the National Institute of Environmental Health Sciences, it includes any process that alters gene activity without changing the actual DNA sequence and that leads to modifications that can pass to offspring. Essentially, it involves information added to the DNA sequence of four bases: adenine (A), guanine (G), cytosine (C), and thymine (T).

The sequence of these bases forms the genetic code for development and functioning – essentially the blueprint for every living thing. Epigenetics changes an organism by changing which genes are expressed – essentially turned on or off – without changing that basic blueprint. In other words, epigenetics results in a change through modification of gene expression rather than alteration of the genetic code itself.

Epigenetic changes can be caused by many outside stimuli, from chemicals to trauma to exercise. And unlike a genetic change or mutation, an epigenetic change can reverse if the stimulus is removed. Many epigenetic changes are positive, or even essential, but some cause serious adverse health and behavioral effects.

Years of analysis have shown that the spaceflight environment changes gene expression in every organism and cell type. Epigenetics could help scientists figure out how that happens and why. Studying epigenetics could reveal the pathway that cells use to adapt and survive in microgravity and reveal ways to control positive changes or prevent negative ones.

The Epigenetics investigation from JAXA (Japan Aerospace Exploration Agency) looked at whether the round worm C. elegans experienced epigenetic changes and if those changes transmitted from one generation to another. Researchers did observe epigenetic changes and concluded that the expression of certain genes, including negative regulators of growth and development, is epigenetically fine-tuned to adapt to microgravity.1

ESA astronaut Samantha Cristoforetti prepares samples for the Epigenetics experiment. Credits: NASA Alt text: Cristoforetti wears a red short-sleeved shirt, olive green pants, and light blue gloves. She is holding a plastic pouch connected by a tube to a panel on the wall of the space station that has multiple cords and displays. The walls around her other devices, cords, and screens.
ESA astronaut Samantha Cristoforetti prepares samples for the Epigenetics experiment.

JAXA’s Mouse Epigenetics studied altered gene expression patterns in mice and DNA changes in their offspring. The investigation identified genetic alterations that happen after exposure to the microgravity environment of space.

An Italian Space Agency study of the bone loss experienced by astronauts on extended missions is associated with epigenetic alterations. Role of the Endocannabinoid System in Pluripotent Human Stem Cell Reprogramming under Microgravity Conditions (SERISM) evaluated the formation of bone cells in microgravity using human blood-derived stem cells as a model. Researchers reported specific epigenetic changes that occurred in the cells in space.2

APEX-03 plates containing Arabidopsis thaliana plants. Credits: NASA Alt text: Plants with green leaves amid a tangle of white roots are visible inside a clear plastic box with an orange clip on each side. White labels can be seen through the box.
APEX-03 plates containing Arabidopsis thaliana plants.

One epigenetic process that researchers can detect is methylation, the addition or removal of a methyl group (CH3) into DNA bases, predominantly where cytosine or C bases occur consecutively. The APEX-03-1 and APEX-03-2 experiments examined DNA methylation and gene expression in Arabidopsis thaliana plants grown from seeds aboard the space station and found widespread changes in patterns of gene expression.3 They also observed epigenetic changes, indicating that they play a role in a plant’s physiological adaptation to spaceflight.4

APEX-04 confirmed this finding. When investigators disrupted the ability of a plant to make those epigenetic changes, that plant struggled more in space.5 Plant Habitat-03 then examined whether these epigenetic changes pass to subsequent generations.

In general, this work showed that plants change gene expression patterns when they experience strange environments and use epigenetic processes to mark genes that help prepare the next generation for the same environment. Those markers show which genes are important for the plant to live in space. Researchers can use that information to breed plants better adapted to space and to harsh environments on Earth.

The MinION DNA sequencer in use on the space station. Credits: NASA Alt text: A blue-gloved hand holds a rectangular palm-sized device. The lid of the device is open revealing a small yellow cell and some labels. There is a USB  cord coming out of the end of the device.
The MinION DNA sequencer in use on the space station.

Expect to see more research on epigenetics on orbit now that more tools are available to provide the ability to immediately sequence DNA at the level that reveals epigenetic changes such as methylation. Traditional DNA sequencers do not provide that level of information without prior processing of the sample, but the space station’s MinION can. Scientists can use these tools to get real-time snapshots of changes as they are happening and potentially how they are passed to subsequent generations.

Melissa Gaskill

International Space Station Program Science Office
Johnson Space Center

Search this database of scientific experiments to learn more about those mentioned above.


1 Higashitani A, Hashizume T, Takiura M, Higashitani N, Teranishi M, Oshima R, Yano S, Kuriyama K, Higashibata A. Histone deacetylase HDA-4-mediated epigenetic regulation in space-flown C. elegans. npj Microgravity. 2021 September 1; 7(1): 33. DOI: 10.1038/s41526-021-00163-7.PMID: 34471121.

2 Gambacurta A, Merlini G, Ruggiero C, Diedenhofen G, Battista N, Bari M, Balsamo M, Piccirillo S, Valentini G, Mascetti G, Maccarrone M. Human osteogenic differentiation in Space: proteomic and epigenetic clues to better understand osteoporosis. Scientific Reports. 2019 June 6; 9(1): 8343. DOI: 10.1038/s41598-019-44593-6.PMID: 31171801.

3 Nakashima J, Pattathil S, Avci U, Chin S, Sparks JA, Hahn MG, Gilroy S, Blancaflor EB. Glycome profiling and immunohistochemistry uncover changes in cell walls of Arabidopsis thaliana roots during spaceflight. npj Microgravity. 2023 August 22; 9(1): 1-13. DOI: 10.1038/s41526-023-00312-0.

4 Zhou M, Sng NJ, LeFrois CE, Paul AL, Ferl RJ. Epigenomics in an extraterrestrial environment: Organ-specific alteration of DNA methylation and gene expression elicited by spaceflight in Arabidopsis thaliana. BMC Genomics. 2019 March 12; 20(1): 205. DOI: 10.1186/s12864-019-5554-z.

5 Paul AL, Haveman NJ, Califar B, Ferl RJ. Epigenomic regulators elongator complex subunit 2 and methyltransferase 1 differentially condition the spaceflight response in Arabidopsis. Frontiers in Plant Science. 2021 September 13; 12691790. DOI: 10.3389/fpls.2021.691790.

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      Jan Pisek [University of Tartu/Tartu Observatory, Estonia] reported on the verification of the previously modeled link between the directional area scattering factor (DASF) from the EPIC VESDR product and foliage clumping with empirical data. The results suggest that DASF can be accurately derived from satellite observations and provide new evidence that the photon recollision probability theory concepts can be successfully applied even at a fairly coarse spatial resolution.
      Sun Glint
      Tamás Várnai [UMBC] discussed the EPIC Glint Product as well as impacts of sun glint off ice clouds on other EPIC data products – see Figure 3. The cloud glints come mostly from horizontally oriented ice crystals and have strong impact in EPIC cloud retrievals. Glints increase retrieved cloud fraction, the retrieved cloud optical depth, and cloud height. Várnai also reported that the EPIC glint product is now available at the ASDC. It is expected that glints yield additional new insights about the microphysical and radiative properties of ice clouds.
      Figure 3. EPIC image taken over Mexico on July 4, 2018. The red, white and blue spot over central Mexico is the result of Sun glint reflecting off high clouds containing ice crystals. EPIC is particularly well suited for studies of ice clouds that cause Sun glint, because unlike most other instruments, it uses a filter wheel to take images at multiple wavelengths, which means the image for each wavelength is obtained at a slightly different time. For example, it takes four minutes to cycle from red to blue. During that time, Earth moves by ~100 km (~62 mi) meaning each image will capture a slightly different scene. Brightness contrasts between images can be used to identify glint signals. Image credit: Tamas Vanai Alexander Kostinski [Michigan Technology University] reported on long-term changes and semi-permanent features, e.g., ocean glitter. They introduced pixel-pinned temporally and conditionally averaged reflectance images, uniquely suited to the EPIC observational circumstances. The preliminary resulting images (maps), averaged over months and conditioned on cover type (land, ocean, or clouds), show seasonal dependence at a glance (e.g., by an apparent extent of polar caps).
      More EPIC Science Results
      Guoyong Wen [Morgan State University] discussed spectral properties of the EPIC observations near backscattering, including four cases when the scattering angle reaches about 178° (only 2° from perfect backscattering). The enhancement addresses changes in scattering angle observed in 2020. (Scattering angle is a function of wavelength, because according to Mie scattering theory, the cloud scattering phase function in the glory region is wavelength dependent.) Radiative transfer calculations showed that the change in scattering angles has the largest impact on reflectance in the red and NIR channels at 680 nm and 780 nm and the smallest influence on reflectance in the UV channel at 388 nm – consistent with EPIC observations. The change of global average cloud amount also plays an important role in the reflectance enhancement.
      Nick Gorkavyi [SSAI] talked about future plans to deploy a wide-angle camera and a multislit spectrometer on the Moon’s surface for whole-Earth observations to complement EPIC observations. Gorkavyi explained that the apparent vibrational movement of Earth in the Moon’s sky complicates observations of Earth. This causes the center of Earth to move in the Moon’s sky in a rectangle, measuring 13.4° × 15.8° with a period of 6 years. 
      Jay Herman [UMBC] reported on EPIC O3 and trends from combining Nimbus 7/Solar Backscatter Ultraviolet (SBUV), the SBUV-2 series, and OMPS–Nadir Mapper (NM) data. (OMPS is made up of three instruments: a Nadir Mapper (NM), Nadir Profiler, and Limb Profiler. OMPS NM is a total ozone sensor). Herman compared EPIC O3 data to OMPS NM data, which showed good agreement (especially summer values) for moderate solar zenith angle (SZA). Comparison with long-term O3 time series (1978–2021) revealed that there were trends and latitude dependent O3 turn-around dates (1994–1998). Herman emphasized that global O3 models do not show this effect but rather have only a single turn-around date around 2000.
      Alexander Radkevich [LaRC] presented a poster that showed a comparative analysis of air quality monitoring by orbital and suborbital NASA missions using the DSCOVR EPIC O3 product as well as Pandora total O3 column retrievals. Comparison of the June 2023 total column O3 from EPIC data to the same periods in previous years revealed a significant – around 50 DU – increase of total O3 column in the areas impacted by the plume from 2023 Canadian wildfires.
      At the end of the meeting Alexander Marshak, Jay Herman, and Adam Szabo discussed how to make the EPIC and NISTAR instruments more visible in the community. The EPIC website now allows visitors to observe daily fluctuations of aerosol index, cloud fraction, and the ocean surface – as observed from the “L1” point,  nearly one million miles away from Earth! More daily products, (e.g., cloud and aerosol height, total leaf area index, and sunlit leaf area index) will be added soon.
      The 2023 DSCOVR EPIC and NISTAR Science Team Meeting provided an opportunity to learn the status of DSCOVR’s Earth-observing instruments, EPIC and NISTAR, the status of recently released L2 data products, and the science results being achieved from the “L1” point. As more people use DSCOVR data worldwide, the ST hopes to hear from users and team members at its next meeting. The latest updates from the mission are found on the EPIC website. (UPDATE: The next DSCOVR EPIC and NISTAR STM will be held on October 16–18, 2024. Check the website for more details as the date approaches.)
      Alexander Marshak
      NASA’s Goddard Space Flight Center

      Adam Szabo
      NASA’s Goddard Space Flight Center
      View the full article
    • By NASA
      2 min read
      Voyager 1 Returning Science Data From All Four Instruments
      An artist’s concept of the Voyager spacecraft. NASA/JPL-Caltech The spacecraft has resumed gathering information about interstellar space.
      NASA’s Voyager 1 spacecraft is conducting normal science operations for the first time following a technical issue that arose in November 2023.
      The team partially resolved the issue in April when they prompted the spacecraft to begin returning engineering data, which includes information about the health and status of the spacecraft. On May 19, the mission team executed the second step of that repair process and beamed a command to the spacecraft to begin returning science data. Two of the four science instruments returned to their normal operating modes immediately. Two other instruments required some additional work, but now, all four are returning usable science data.  
      The four instruments study plasma waves, magnetic fields, and particles. Voyager 1 and Voyager 2 are the only spacecraft to directly sample interstellar space, which is the region outside the heliosphere — the protective bubble of magnetic fields and solar wind created by the Sun.
      While Voyager 1 is back to conducting science, additional minor work is needed to clean up the effects of the issue. Among other tasks, engineers will resynchronize timekeeping software in the spacecraft’s three onboard computers so they can execute commands at the right time. The team will also perform maintenance on the digital tape recorder, which records some data for the plasma wave instrument that is sent to Earth twice per year. (Most of the Voyagers’ science data is sent directly to Earth and not recorded.)
      Voyager 1 is more than 15 billion miles (24 billion kilometers) from Earth, and Voyager 2 is more than 12 billion miles (20 billion kilometers) from the planet. The probes will mark 47 years of operations later this year. They are NASA’s longest-running and most-distant spacecraft. Both spacecraft flew past Jupiter and Saturn, while Voyager 2 also flew past Uranus and Neptune.
      News Media Contact
      Calla Cofield
      Jet Propulsion Laboratory, Pasadena, Calif.

      Last Updated Jun 13, 2024 Related Terms
      Heliophysics Jet Propulsion Laboratory Voyager 1 Explore More
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      A collaboration between the MSFC Lightning Team, NOAA NESDIS, and the NASA ARSET (Applied Remote Sensing Training) team completed on 4/2/24 with the final installment of a three-part series focused on Lightning Observations and Applications. On 3/26/24, Part 1 was presented to an audience of people from around the globe focused on the background and history of lightning measurements. This presentation was given by Steven Goodman of Thunderbolt Technologies. Part 2 was titled” Overview of Current Lightning Data Products from Remote Sensing” and was given by MSFC Lightning lead Timothy Lang (ST11). This presentation focused a lot on NASA lightning missions, field campaigns, and data access and was given on 3/28/24. The final installment of the ARSET lightning series was given on 4/2/24 by Scott Rudlosky of NOAA NESDIS and Christopher Schultz (ST11) of MSFC. This third part focused specifically on the Geostationary Lightning Mapper and applications of the data for science, identify lightning hazards, and safety. The average total attendance was around 225 people per session. Schultz took a lead role in working with the ARSET team to identify the speakers, topics, and review materials for presentation. Each of the 6 sessions (2 per day per topic, 1.5 hours each session) were followed up with 10-15 questions from the audience. The ARSET team indicates that there is potential for additional lightning-based trainings going forward given the response to this first series.
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    • By NASA
      5 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      Perseverance captured this mosaic looking downstream of the dune-filled Neretva Vallis river channel on May 17. The channel fed Jezero Crater with fresh water billions of years ago.NASA/JPL-Caltech/ASU/MSSS Originally thought of as little more than a route clear of rover-slowing boulders, Neretva Vallis has provided a bounty of geologic options for the science team.   
      After detouring through a dune field to avoid wheel-rattling boulders, NASA’s Perseverance Mars rover reached its latest area of scientific interest on June 9. The route change not only shortened the estimated drive time to reach that area — nicknamed “Bright Angel” — by several weeks, but also gave the science team an opportunity to find exciting geologic features in an ancient river channel.
      Perseverance is in the later stages of its fourth science campaign, looking for evidence of carbonate and olivine deposits in the “Margin Unit,” an area along the inside of Jezero Crater’s rim. Located at the base of the northern channel wall, Bright Angel features rocky light-toned outcrops that may represent either ancient rock exposed by river erosion or sediments that filled the channel. The team hopes to find rocks different from those in the carbonate-and-olivine-rich Margin Unit and gather more clues about Jezero’s history.
      Stitched together from 18 images taken by NASA’s Perseverance rover, this mosaic shows a boulder field on “Mount Washburn” on May 27. Intrigued by the diversity of textures and chemical composition in the light-toned boulder at center, the rover’s science team nicknamed the rock “Atoko Point.”NASA/JPL-Caltech/ASU/MSSS To get to Bright Angel, the rover drove on a ridge along the Neretva Vallis river channel, which billions of years ago carried a large amount of the water that flowed into Jezero Crater. “We started paralleling the channel in late January and were making pretty good progress, but then the boulders became bigger and more numerous,” said Evan Graser, Perseverance’s deputy strategic route planner lead at NASA’s Jet Propulsion Laboratory in Southern California. “What had been drives averaging over a hundred meters per Martian day went down to only tens of meters. It was frustrating.”
      Channel Surfing
      In rough terrain, Evan and his team use rover imagery to plan drives of about 100 feet (30 meters) at a time. To go farther on any given Martian day, or sol, planners rely on Perseverance’s auto-navigation, or AutoNav, system to take over. But as the rocks became more plentiful, AutoNav would, more times than not, determine the going was not to its liking and stop, dimming the prospects of a timely arrival at Bright Angel. The team held out hope, however, knowing they might find success cutting across a quarter-mile (400-meter) dune field in the river channel.
      NASA’s Perseverance rover was traveling in the ancient Neretva Vallis river channel when it captured this view of an area of scientific interest named “Bright Angel” — the light-toned area in the distance at right — with one of its navigation cameras on June 6.NASA/JPL-Caltech “We had been eyeing the river channel just to the north as we went, hoping to find a section where the dunes were small and far enough apart for a rover to pass between — because dunes have been known to eat Mars rovers,” said Graser. “Perseverance also needed an entrance ramp we could safely travel down. When the imagery showed both, we made a beeline for it.”
      The Perseverance science team was also eager to travel through the ancient river channel because they wanted to investigate ancient Martian river processes.
      Rock Star
      With AutoNav helping guide the way on the channel floor, Perseverance covered the 656 feet (200 meters) to the first science stop in one sol. The target: “Mount Washburn,” a hill covered with intriguing boulders, some of a type never observed before on Mars.
      Superimposed on an image from NASA’s Mars Odyssey orbiter, this map shows Perseverance’s path between Jan. 21 and June 11. White dots indicate where the rover stopped after completing a traverse beside Neretva Vallis river channel. The pale blue line indicates the rover’s route inside the channel.NASA/JPL-Caltech/University of Arizona “The diversity of textures and compositions at Mount Washburn was an exciting discovery for the team, as these rocks represent a grab bag of geologic gifts brought down from the crater rim and potentially beyond,” said Brad Garczynski of Western Washington University in Bellingham, the co-lead of the current science campaign.“But among all these different rocks, there was one that really caught our attention.” They nicknamed it “Atoko Point.”
      Some 18 inches (45 centimeters) wide and 14 inches (35 centimeters) tall, the speckled, light-toned boulder stands out in a field of darker ones. Analysis by Perseverance’s SuperCam and Mastcam-Z instruments indicates that the rock is composed of the minerals pyroxene and feldspar. In terms of the size, shape, and arrangement of its mineral grains and crystals — and potentially its chemical composition — Atoko Point it is in a league of its own.
      Some Perseverance scientists speculate the minerals that make up Atoko Point were produced in a subsurface body of magma that is possibly exposed now on the crater rim. Others on the team wonder if the boulder had been created far beyond the walls of Jezero and transported there by the swift Martian waters eons ago. Either way, the team believes that while Atoko is the first of its kind they’ve seen, it won’t be the last.
      After leaving Mount Washburn, the rover headed 433 feet (132 meters) north to investigate the geology of “Tuff Cliff” before making the four-sol, 1,985-foot (605-meter) journey to Bright Angel. Perseverance is currently analyzing a rocky outcrop to assess whether a rock core sample should be collected.
      More About the Mission
      A key objective for Perseverance’s mission on Mars is astrobiology, including caching samples that may contain signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith.
      Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
      The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.
      NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech, built and manages operations of the Perseverance rover.
      For more about Perseverance:
      News Media Contacts
      DC Agle
      Jet Propulsion Laboratory, Pasadena, Calif.
      Karen Fox / Charles Blue
      NASA Headquarters, Washington
      301-286-6284 / 202-802-5345
      karen.c.fox@nasa.gov / charles.e.blue@nasa.gov
      Last Updated Jun 13, 2024 Related Terms
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