New research from Wellesley College has found that two types of weevils, common yet invasive beetles in many parts of the world, have been using epigenetic changes to adapt and respond to different toxins in the plants they eat. The findings, published in PLOS ONE under the title “Host-Specific Gene Expression as a Tool for Introduction Success in Naupactus Parthenogenetic Weevils,” have implications for how we consider asexual invaders and how successful they can be because of gene regulation.

The researchers, led by Andrea Sequeira, Wellesley College Gordon and Althea Lang ’26 Professor of Biological Sciences, collected samples of parthenogenetic, invasive, and polyphagous weevils, Naupactus cervinus and N. leucoloma, from Florida, California, and Argentina over the course of five years, starting in 2015. Despite being from different locations within the United States where they have been introduced, often through commerce, the weevils are asexual and genetically identical. Yet the team found that they have uniquely adapted to produce different proteins that allow them to eat and digest a variety of plants, even those that produce toxins.

Sequeira worked with a talented team: Ava Mackay-Smith, Mary Kate Dornon, Rosalind Lucier, Anna Okimoto, and Flavia Mendonca de Sousa from Wellesley College, and Marcela Rodriguero, Viviana Confalonieri, Analia Lanteri from the University of Buenos Aires and the Museo de Ciencias Naturales in La Plata, Argentina. Together, they analyzed patterns of gene expression in three gene categories that can mediate weevil-host plant interactions through identification of suitable host plants, short-term acclimation to host plant defenses, and long-term adaptation to host plant defenses and their pathogens.

“We found that some host plant groups, such as legumes, appear to be more taxing for weevils and elicit a complex gene expression response,” Sequeira said. “However, the weevil response to taxing host plants shares many differentially expressed genes with other stressful situations, such as organic cultivation conditions and transition to novel hosts, suggesting that there is an evolutionarily favorable shared gene expression regime for responding to different types of stressful situations.”

“We also found that mothers are able to ‘prime’ their young with these epigenetic changes,” lead author and 2020 Wellesley College alumna Ava Mackay-Smith said. “Originally, we thought that these changes would only be seen in a single generation. When we studied larvae, who do not yet have mouths or eat plants, we found evidence of the same proteins and adaptations from their mothers.”

Sequeira noted this finding is especially important because classic understanding has been that in both sexual and asexual reproduction, all epigenetic marks are erased between generations and each generation starts over.

Mackay-Smith believes that having a better understanding of epigenetic changes in invasive, asexual species may eventually help regulate or mitigate their potential negative impact on an environment, native plants, or crops, for example. “Knowing what is in this insect’s repertoire, you could imagine that since we’ve now identified the proteins that are regulated differently, you could target a specific protein and design a targeted pesticide that removes only that species of weevil, without harming other native insects or fauna.”

Both Mackay-Smith and Sequeira are excited to see that perhaps genetic variation is not the only form of heritable variation for natural selection to act upon and that epigenetic processes may increase the evolutionary potential of organisms in response to stress and other environmental challenges — adaptations that could be relevant in the context of climate change.

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These alien worlds, called super-Jupiters, weigh up to 13 times Jupiter’s mass. Astronomers have analyzed the composition of some of these monsters, but it has been difficult to study their atmospheres in detail because these gas giants get lost in the glare of their parent stars.

Researchers, however, have a substitute: the atmospheres of brown dwarfs, so-called failed stars that are up to 80 times Jupiter’s mass. These hefty objects form out of a collapsing cloud of gas, as stars do, but lack the mass to become hot enough to sustain nuclear fusion in their cores, which powers stars.

Instead, brown dwarfs share a kinship with super-Jupiters. Both types of objects have similar temperatures and are extremely massive. They also have complex, varied atmospheres. The only difference, astronomers think, is their pedigree. Super-Jupiters form around stars; brown dwarfs often form in isolation.

A team of astronomers, led by Elena Manjavacas of the Space Telescope Science Institute in Baltimore, Maryland, has tested a new way to peer through the cloud layers of these nomadic objects. The researchers used an instrument at W. M. Keck Observatory on Maunakea in Hawaii to study in near-infrared light the colors and brightness variations of the layer-cake cloud structure in the nearby, free-floating brown dwarf known as 2MASS J22081363+2921215.

The Keck Observatory instrument, called the Multi-Object Spectrograph for Infrared Exploration (MOSFIRE), also analyzed the spectral fingerprints of various chemical elements contained in the clouds and how they change with time. This is the first time astronomers have used MOSFIRE in this type of study.

These measurements offered Manjavacas a holistic view of the brown dwarf’s atmospheric clouds, providing more detail than previous observations of this object. Pioneered by Hubble observations, this technique is difficult for ground-based telescopes to do because of contamination from Earth’s atmosphere, which absorbs certain infrared wavelengths. This absorption rate changes due to the weather.

“The only way to do this from the ground is by using Keck’s high-resolution MOSFIRE instrument because it allows us to observe multiple stars simultaneously with our brown dwarf,” said Manjavacas, a former staff astronomer at Keck Observatory and the lead author of the study. “This allows us to correct for the contamination introduced by the Earth’s atmosphere and measure the true signal from the brown dwarf with good precision. So, these observations are a proof-of-concept that MOSFIRE can do these types of studies of brown dwarf atmospheres.”

She decided to study this particular brown dwarf because it is very young and therefore extremely bright. It has not cooled off yet. Its mass and temperature are similar to those of the nearby giant exoplanet Beta Pictoris b, discovered in 2008 near-infrared images taken by the European Southern Observatory’s Very Large Telescope in northern Chile.

“We don’t have the ability yet with current technology to analyze in detail the atmosphere of Beta Pictoris b,” Manjavacas said. “So, we’re using our study of this brown dwarf’s atmosphere as a proxy to get an idea of what the exoplanet’s clouds might look like at different heights of its atmosphere.”

Both the brown dwarf and Beta Pictoris b are young, so they radiate heat strongly in the near-infrared. They are both members of a flock of stars and sub-stellar objects called the Beta Pictoris moving group, which shares the same origin and a common motion through space. The group, which is about 33 million years old, is the closest grouping of young stars to Earth. It is located roughly 115 light-years away.

While they’re cooler than bona fide stars, brown dwarfs are still extremely hot. The brown dwarf in Manjavacas’ study is a sizzling 2,780 degrees Fahrenheit (1,527 degrees Celsius).

The giant object is about 12 times heavier than Jupiter. As a young body, it is spinning incredibly fast, completing a rotation every 3.5 hours, compared to Jupiter’s 10-hour rotation period. So, clouds are whipping around the planet, creating a dynamic, turbulent atmosphere.

Keck Observatory’s MOSFIRE instrument stared at the brown dwarf for 2.5 hours, watching how the light filtering up through the atmosphere from the dwarf’s hot interior brightens and dims over time. Bright spots that appeared on the rotating object indicate regions where researchers can see deeper into the atmosphere, where it is hotter. Infrared wavelengths allow astronomers to peer deeper into the atmosphere. The observations suggest the brown dwarf has a mottled atmosphere with scattered clouds. If viewed close-up, the planet might resemble a carved Halloween pumpkin, with light escaping from the hot interior.

Its spectrum reveals clouds of hot sand grains and other exotic elements. Potassium iodide traces the object’s upper atmosphere, which also includes magnesium silicate clouds. Moving down in the atmosphere is a layer of sodium iodide and magnesium silicate clouds. The final layer consists of aluminum oxide clouds. The atmosphere’s total depth is 446 miles (718 kilometers). The elements detected represent a typical part of the composition of brown dwarf atmospheres, Manjavacas said.

She and her team used computer models of brown dwarf atmospheres to determine the location of the chemical compounds in each cloud layer.

The study will be published in The Astronomical Journal.

Manjavacas’ plan is to use Keck Observatory’s MOSFIRE to study other atmospheres of brown dwarfs and compare them to those of gas giants. Future telescopes such as NASA’s James Webb Space Telescope, an infrared observatory scheduled to launch later this year, will provide even more information about a brown dwarf’s atmosphere.

“JWST will give us the structure of the entire atmosphere, providing more coverage than any other telescope,” Manjavacas said.

She hopes that MOSFIRE can be used in tandem with JWST to sample a wide range of brown dwarfs and gain a better understanding of brown dwarfs and giant planets.

“Exoplanets are so much more diverse than what we see locally in the solar system,” said Keck Observatory Chief Scientist John O’Meara. “It’s work like this, and future work with Keck and JWST, that will give us a fuller picture of the diversity of planets orbiting other stars.”

The islands that make up Japan form a long arc that extends from tropical regions in the south to Palearctic regions in the north. Permafrost has been reported to exist in the Daisetsu Mountains, Mt. Fuji and Mt. Tateyama. The Daisetsu Mountains on the northern island of Hokkaido, which are known to support a variety of alpine plants and animals, are also a valuable natural resource that is visited by numerous climbers every year. However, there is some concern that the thawing of permafrost will have a major impact on this mountain ecosystem. No projections of future permafrost distribution have been undertaken in East Asia, including in Japan, to date.

In this study, by applying the statistical method developed in a previous study for estimating the permafrost distribution to outputs from bias-corrected and downscaled climate model with a 1 km resolution for the area of interest, we investigated the climatic conditions required to sustain permafrost in the Daisetsu Mountains.

Researchers have studied the climate conditions suitable to maintain permafrost in the Daisetsu Mountains. The region of the climate conditions suitable to maintain permafrost starts to decrease significantly in size from around 2000, and under both the low-carbon scenario consistent with Paris target (RCP2.6) and busines-as-usual scenario (RCP8.5). The steep decline in the region at the end of the 20th century occurs because the surface air temperature increases significantly from around the year 2000 onward. The size of the area in the Daisetsu Mountains where climatic conditions were suitable for permafrost were estimated to be approximately 150 km2 in 2010. Under the RCP8.5 scenario, this area is projected to disappear by around 2070. Under the RCP2.6 scenario, the area is projected to decrease to approximately 20 km² by 2100.

The finding that the climatic conditions of the Daisetsu Mountains are projected to shift towards conditions where permafrost will disappear regardless of the climate scenario used, indicates the importance of impact assessments and developing adaptation measures to climate change. Thawing of permafrost can have a significant impact on the surface vegetation and alpine ecosystems. Previous studies have shown that the thawing of permafrost can have a variety of adverse effects, including lowering groundwater levels and replacement of alpine meadows by steppes, extensive desertification such as that in the eastern and western parts of the Tibetan Plateau, and a decrease in species diversity due to warming. Moreover, thawing of the frozen ground reduces the stability of the ground in mountain regions, potentially increasing the frequency and magnitude of rock falls and landslides, which may affect the safety of trekkers that visit the Daisetsu Mountains annually. In order to deal with these problems, it is very important to monitor the environmental changes in mountainous areas. In addition to accurately monitoring changes in mountain environments, providing local governments with appropriate measures to prepare for major future environmental changes, as shown in this study, is an important issue for the future.

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The study findings appear online in 4Open, a journal published by EDP Sciences.

“HCC accounts for nearly 90% of all liver cancers, and current survival rates are between six and 20 months,” said Boris Pasche, M.D., Ph.D., chair of cancer biology and director of Wake Forest Baptist’s Comprehensive Cancer Center. “Currently, there are limited treatment options for patients with this advanced liver cancer.”

For the study researchers used a device called TheraBionic P1, invented by Pasche and Alexandre Barbault of TheraBionic GmbH in Ettlingen, Germany, that works by delivering cancer-specific, amplitude-modulated radiofrequency electromagnetic fields (AM RF EMF) programmed specifically for HCC.

The frequencies used are specific to the patient’s type of cancer as identified through tumor biopsies or blood work, Pasche said.

Pasche and Barbault discovered radio frequencies for 15 different types of cancer, as previously reported in a study published in 2009 in the Journal of Experimental & Clinical Cancer Research.

TheraBionic P1 is a hand-held device that emits radio frequencies via a spoon-shaped antenna, which is placed on the patient’s tongue during treatment and is administered three times a day for one hour to deliver low levels of radiofrequency electromagnetic fields throughout the patient’s body.

In previous studies, the device, which received breakthrough designation from the FDA in 2019, was shown to block the growth of liver cancer cells in the body without damaging healthy cells.

For the current study, 18 patients with advanced HCC participated and received treatment with the device. Researchers also analyzed previously published data on 41 patients from a phase II study and historical controls from earlier clinical trials.

“Our findings show an improvement in overall survival of more than 30% in patients with well-preserved liver function and also in those with more severe disease,” Pasche said.

Researchers also tracked side effects, and no patients stopped TheraBionic P1 treatment because of adverse reactions.

“We’re encouraged by these initial findings,” Pasche said. “Our study shows a benefit in overall survival, and the treatment isn’t associated with any significant side effects.”

Support for this study was provided by TheraBionic Inc. and funds from Wake Forest Baptist’s Comprehensive Cancer Center.

Pasche noted that the study does have several limitations because of the small sample size and “selection bias inherent in the use of historical control data.”

However, two additional clinical trials are underway and are being led by William Blackstock, M.D., chair of radiation oncology at Wake Forest Baptist’s Comprehensive Cancer Center. One is a single-center study to assess the safety and effectiveness of the TheraBionic device in combination with Regorafenib, a chemotherapy drug, as a second-line treatment. Another multicenter, double-blind, randomized study comparing TheraBionic with placebo will assess the safety and effectiveness of the device as a third-line therapy in the treatment of advanced HCC.

Pasche holds stock in TheraBionic Inc. and TheraBionic GmbH. He is chairman of the board and CEO of TheraBionic Inc. and co-CEO of TheraBionic GmbH. He is also a senior editorial board member of Life Sciences-Medicine of 4Open by EDP Sciences. These relationships are being managed per institutional policy by Wake Forest School of Medicine’s Conflict of Interest Review Committee.