Space, Biology, and Agriculture: Breakthroughs from Aditya-L1, IISc, and Bt Maize Resistance Study

A historic first: Aditya-L1 captures intense solar flare in unprecedented detail

SOLAR flares occur when the powerful magnetic fields in and around the sun reconnect. They are usually associated with active regions, often seen as sunspots, where the magnetic fields are the strongest. Flares release huge bursts of radiation and energetic particles by a sudden release of the magnetic energy stored in the complex solar magnetic field. Such events can have a serious impact on space weather and geo-space, including disrupting radio communications, affecting satellite operations, interfering with power grids, and even posing risks to astronauts and airline passengers flying near the poles through exposure to small radiation doses.

On February 22, 2024, the Solar Ultraviolet Imaging Telescope (SUIT) on board Aditya-L1—India’s first dedicated solar space mission, which was launched on September 2, 2023—captured in unprecedented detail the “kernel” of a solar flare in the lower solar atmosphere, namely the photosphere and the chromospheres. This significant observation, in the near-ultraviolet band, marks a leap in the understanding of explosive activities in the solar atmosphere.

It was an X6.3-class solar flare on that day, one of the most intense categories of solar eruptions, and it was the strongest flare in six years. This eruption is the largest so far in the current solar cycle. (Flares are classified according to their strength, the smallest ones being B-class, followed by C, M, and X, the largest. Each letter represents a tenfold increase in energy output over the previous. Within each, there is a finer scale from 1 to 9. There are flares more than 10 times the power of an X1. The most powerful flare on record was in 2003, whose strength was estimated to be X45.)

The uniqueness of the Aditya-L1 discovery is that SUIT detected brightening in the near-UV wavelength range (200-400 nanometres). The properties of solar flares have never been studied in this band primarily due to a lack of dedicated space telescopes in this wavelength band. Space telescopes are necessary for that as UV radiation gets absorbed by the earth’s atmosphere.

According to the release from the Inter-University Centre for Astronomy and Astrophysics, Pune, one of the participating institutions in the Aditya-L1 mission, the full disk of the sun has never been imaged in this entire wavelength range in such detail. “These observations provide new insights into these huge eruptions in the solar atmosphere and highlight the complex physical processes involved in the transfer of mass and energy through different layers of the solar atmosphere,” the release said.

A significant insight from the detection of kernel of this flare in the photosphere is that the layers below the chromospheres were also affected. Another exciting revelation is that SUIT’s detection of localised brightening directly corresponds with the increase in temperature of the plasma in the solar corona at the top of the atmosphere. This observation of direct link between the heating of the plasma and flare energy deposition has validated long-standing theoretical predictions. The findings of Aditya-L1 were published in a recent issue of The Astrophysical Journal Letters.

Unlocking the hidden power of ‘transactivation domains’ in yeast

RESEARCHERS at the Department of Biochemistry, Indian Institute of Science (IISc), Bengaluru, have discovered that tiny segments of a transcription factor (TF)—a protein that controls how genes are turned on and off—containing just nine amino acids can independently activate genes in Komagataella phaffii (formerly Pichia pastoris), a yeast widely used in biotechnology and pharmaceutical industries to produce proteins for food and medicines. Their work, which was recently published in Journal of Biological Chemistry, challenges the belief that large, complex protein segments or structures are needed for gene activation.

The researchers focussed on Mxr1, a zinc finger TF (ZTF), which binds to zinc ions and thereby recognises and binds to specific DNA sites. ZTF controls key metabolic genes in the yeast. The team engineered 21 synthetic TFs, each with Mxr1’s DNA-binding domain and 3 copies of putative 9-amino acid transactivation domains, which are regions of TFs that contain binding sites for proteins and activate gene transcription. Significantly, 11 of these factors successfully restored gene expression in yeast lacking Mxr1 as efficiently as the wild type protein. This discovery has major implications for biotechnology, particularly for optimising K. phaffii as a host for producing recombinant proteins.

According to the release from the IISc, Mxr1 regulates the enzyme aldehyde oxidase 1, which plays an important role in methanol metabolism; its promoter is widely used for high-level protein expression. Harnessing these minimal yet powerful activation domains could lead to the development of novel yeast strains for commercial production of vaccines, therapeutic proteins, food additives, and industrial enzymes, says the release. This advancement paves the way for next-generation approaches in synthetic biology and genetic engineering, proving that small molecular tools can drive efficient, scalable biological systems.

Consequences of overplanting rootworm resistant Bt maize in the US Corn Belt

GENETICALLY engineered crops, particularly those incorporating insecticidal proteins from Bacillus thuringiensis (Bt), have significantly boosted global food production by reducing pest damage. However, as the use of Bt crops increases, pests inevitably develop resistance, diminishing the effectiveness of the technology over time. In this case, resistance began emerging in 2009, according to the authors.

The widespread use of Bt maize, designed to combat rootworm pests, has led to overplanting and pest resistance, jeopardising the crop’s long-term effectiveness, according to a new US-China collaborative study based on data from 10 US “Corn Belt” States.

Using data relating to 12 years of field trials and farmers’ seed usage across these 10 States, Ziwei Ye and colleagues evaluated the economic consequences of diverging from optimal rootworm Bt maize planting levels. The researchers found that while pest pressure decreased as a result of pest suppression by Bt maize, increased planting of this crop has undermined its anti-rootworm effectiveness.

Moreover, a cost-benefit analysis from 2014 to 2016 showed that Bt maize was often planted excessively, particularly in the eastern Corn Belt States, where pest pressure was low. This overuse led to minimal pest suppression benefits, higher costs for the transgenic seed, and a significant depletion of the pest susceptibility pool, resulting in an estimated $1.6 billion in lifetime economic losses for growers in these regions. These findings emphasise the need for improved seed diversity, transparency, and farmer decision-making to sustain transgenic crop benefits.

“If current and future related innovations are managed as Bt maize hybrids have been,” say the authors, “we risk entering a cycle of rapid obsolescence among transgenic technologies.”

The study results were published in the latest issue of Science.