Sponsored Research

We study two proteins, hERG and KvLQT1, found in heart muscle cells. These two proteins form ion channels, tunnels through the cell membrane that allow ions to move into or out of the cell in a selective and controlled way. The movement and balance of ions set the pace of a normal human heartbeat. When the pace is disrupted, people can experience irregular heartbeats, heart damage, or sudden cardiac death. We think that hERG and KvLQT1 function less well when they are connected or bound to each other. This could increase the chance of irregular heartbeats. Thus we are interested in what cellular signals tell hERG and KvLQT1 to bind or to release. We have shown that the final signal step in the "fight or flight" response of organisms chemically alters hERG and KvLQT1 proteins. This chemical change seems to cause the two proteins to release each other. In this proposal we will study the multiple places where this chemical change can happen in both hERG and KvLQT1. We think we will see different levels of binding depending on the extent and location each protein is altered. We will also study whether these chemical changes cause more or less hERG and KvLQT1 to be present in the cell membrane. An increase in protein amount in the cell membrane would allow more ions to flow, helping maintain a normal heartbeat. Overall our work may connect protein-protein interactions to the rhythmic functioning or malfunctioning of human hearts.

Brain structure and function are sensitive and responsive to environmental conditions and individual experiences such as nutrition, gut microbiome, household environment and levels of stress. The main goals of this multi-scale, and multi-modal study is to comprehensively characterize the development of executive functions over the first 1000 days of life in two African cohorts (South Africa and Malawi) to identify developmental patterns, windows for intervention, and inform on therapeutic agents. Here at Wellesley, we will characterize the gut microbiome collected over the first two years of life and link the acquisition of the microbiome to executive functions.

Despite affecting nearly 20% of infants in the United States, there is no cure for atopic dermatitis/eczema. Some parents feed their infants human milk in an effort to protect the infant from developing this disease, but the efficacy of this intervention is unclear. This project will determine if the presence of specific bacterial genes or bacterial metabolic products in the intestinal tract during early life in two different infant cohorts, while the immune system is still fully developing, can protect the infant from atopic dermatitis/eczema. Much of this work will be carried out by students at Wellesley College and undergraduate students at Michigan State University. Performing this research in two different regions of the US will be especially advantageous, since subtle differences in medical or cultural practices, or simply geographic differences in microbial exposure, may alter HMO metabolizing gene repertoires independent of breastfeeding behavior. This research will dramatically improve our understanding of microbial HMO metabolism in human infants in the United States and determine whether a specific pattern of HMO metabolizing genes protects infants from atopic dermatitis and eczema.

Phenotypic plasticity refers to the ability of an organism to generate distinct morphological, behavioral or metabolic changes in response to environmental changes. Laboratory and theoretical research has shown that phenotypic plasticity may play an important role in shaping the evolutionary trajectory of species, although the underlying mechanism remains poorly understood. Research in our lab investigates the molecular and physiological basis of phenotypic plasticity in artificially selected insects that exhibit distinct amounts of plasticity and aims to identify key regulators of hormonal systems. Much of the work is carried out by students at Wellesley College. Determining the molecular mechanism by which phenotypic plasticity evolves has implications for our understanding of evolution and may also help identify novel regulators that may serve as potential targets for pest management.

Developmental plasticity has dramatic effects on the survival and reproductive fitness of organisms. In many organisms, including humans, changes in developmental physiology initiate dramatic alterations in growth and morphology. Attainment of particular body size thresholds triggers these changes in developmental physiology; however, we do not yet know how an organism senses its body size. Research in the Suzuki lab aims to answer this issue by studying the transcriptional regulation of developmental hormones in arthropods (insects and crustaceans) and experimentally manipulating conditions that alter the body size thresholds. Our current work focuses on genes that regulate the production of ecdysteroids and juvenile hormone. In particular, we focus on the endocrine roles of the POU transcription factor, ventral veins lacking, which has been demonstrated to play a key role in regulating hormone biosynthesis. Given the current trend towards precocious puberty onset among youth, understanding the regulation of developmental transitions will have important medical and public health implications.

My current research project addresses the anatomical transformation of the shoulder girdle that occurred during the evolutionary transition from synapsid reptiles to mammals. The sternum integrates the head, neck, chest, and limbs, and plays a key role in establishing patterning along the anterior-posterior axis of the body. Specifically, my students and I ask whether the sternum of living mammals is a single element, or the fusion product of multiple ancestral elements, each with a unique developmental history and peripheral articulation. We use CT scans of fetal whales to document sternal structure along the timeline of an individual’s development, and fossil ground sloths and armadillos to document changes over evolutionary history.

Forest insects and pathogens are global agents of ecosystem disturbance. In the United States, tree stress and mortality from insects and pathogens creates billions of dollars in costs for U.S. municipalities and individual property owners. The interactions between insects and pathogens and other disturbances, such as climate change, are highly uncertain, but in many cases climate change is expected to increase insect and pathogen activity. This project will develop a framework to simulate and forecast the impacts of forest insects and pathogens through a generalized method that accurately captures the large diversity of their impacts. This framework will be used to simulate the potential impacts of insect and pathogen outbreaks in forests across the continental U.S. and to investigate the specific impacts of three invasive insects –Lymantria dispar, Agrilus planipennis, and Adelges tsugae – in the northeastern U.S. A key benefit of this research is that it will improve the ability to simulate future impacts of insects and pathogens on forests in combination with other disturbances like drought, heat waves, and extreme rainfall events. This research will also increase the diversity of the U.S. STEM workforce by training undergraduate women in cutting-edge quantitative methods.

The trillions of microbes inhabiting our bodies are essential for extracting nutrients from our food to maintaining the health of our immune systems. There is a growing recognition that the microbiome is directly linked to the health and development of infants and children. Research in our lab and in collaboration with several universities and research centers across the country brings together the gut microbiome, human genetics, nutrition, and cognitive development to improve our understanding of environmental influences on health outcomes in children. The longitudinal study follows over 1000 children between the ages of 0 to 12 years. As such, the study provides an ideal system for investigating the relationships among microbes, their resilience and stability, and their interactions with the human body.

As a part of the Hubbard Brook Ecosystem Study (hubbardbrook.org), I am investigating how climate, weather and the abundance of insects and nest predators affect the distribution, demography and population dynamics of songbirds in a northern hardwood forest, Hubbard Brook Experimental Forest, New Hampshire.

The overarching research theme of the Hubbard Brook Ecosystem Study (HBES) is the response of ecosystem structure, composition and function to disturbance. Disturbances, both natural and anthropogenic, are the most important factors driving change at the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire and throughout the Northern Forest region. Predicting the future of these forested landscapes requires a comprehensive understanding of multiple disturbances and their interactions. Some of these disturbances are chronic and long-term, such as gradual changes in average temperature and precipitation or the steady progression of beech bark disease. Others are intense and episodic, such as ice storms, wind storms, and insect outbreaks. Moreover, these disturbances may leave legacies that affect the forest, and its response to future disturbances, for decades or centuries. In this project, Matthes and her students work to understand the long-term feedbacks between soil processes, plant physiology, and tree community composition, structure, and function.

The plant vascular system is of critical importance for normal plant growth, development and function, yet the mechanisms that govern development of the intricate and beautiful vascular patterns we observe in nature, are largely unknown. The vascular patterns of leaves and cotyledons provide a convenient system for addressing this complex problem. The process begins when narrow files of cells are recruited in a pattern that predicts the final venation pattern. These cells subsequently become committed to a vascular fate and differentiate into the procambium, a stem cell population that will ultimately produce the conducting tissues of the veins – xylem and phloem.  Research in the Peterman lab is exploring the cellular and molecular mechanisms required for establishment of this critical stem cell population in the flowering plant model organism, Arabidopsis thaliana. Specifically, this project aims to define the role of the Sec14-related proteins, PATELLIN-1 and -2, in membrane trafficking events critical to the formation of the procambium. The enhanced understanding of how the plant vascular systems develops that will result from this project may prove useful in designing genetic modifications of plants of agronomic importance. This is particularly relevant for plants used for biofuels since xylem, makes up the bulk of plant biomass, an increasingly valuable source of renewable energy.

Locomotion and feeding are essential behaviors for the survival and reproductive fitness of most animals. However, little is understood about why some individuals within a population outperform others and are better suited to their habitat. Populations of bluegill sunfish often diverge into two different body forms based on their habitat: a deeper-bodied shallow water form or a streamlined deep water form. This variation creates an ideal system for investigating the relationships between form, function and adaptation to habitat.