When most people thinking of harvesting material from apis mellifera, they think about honey. Apis mellifera is, after all, the scientific name of the honeybee. That's not the case for Sarah Bertino '09 (Natick, Mass.), working under the advisement of Associate Professor of Biology and Director of the Neuroscience Program Herman Lehman. When Bertino sets out to harvest from bees, she's after their brains. She has about 30 seconds to extract the brain from the bee on the dry ice beside her and isolate it in a small test tube before the brain liquefies. That's just the beginning of a bizarre and captivating trail leading to an intimate connection with the human brain that holds the promise of yielding answers to the mechanisms of Parkinson's disease, schizophrenia and attention deficit hyperactivity disorder (ADHD).
Bertino skillfully pins her bee and extracts the brain with several seconds to spare. She performs the act calmly; she's done this hundreds of times. Nevertheless, she takes all the care of a cardiologist during an open-heart surgery. "Every brain is precious," she explains. "I don't want to waste any." Bertino points out that not all bees are the same. "The bee I just finished with was a forager. A bee starts as a nurse, working around the hive, and then gradually becomes a soldier, working the edges. Finally, it becomes a forager and flies out to find food for the community." As the bees progress from being nurses to foragers, the levels of a key enzyme, called octopamine, increase. One of the main objects of Bertino's project is to attempt to discover a correlation between the increase of octopamine in the bee brains and an increase in another enzyme or enzymes within the bees over the progression of the life cycle. It's more difficult than it might seem.
"Originally," says Bertino, "people thought that tyramine beta-hydroxylase (TBH) was the enzyme in charge, since TBH is the enzyme that is closest to octopamine in the progression along the pathway by which octopamine is formed from tyrosine, but the levels of TBH don't increase in foragers." Using a complex system of gels (which separate proteins by size), Western blots (modified gels), polymerase chain reactions (PCR) and various enzymes that cut, replicate or alter DNA, Bertino is now trying to discover if levels of another major player in the bee's brain, juvenile hormone (JH), significantly rise or lower in the transition from nurse to forager and whether that change could be linked to, or causing, the rise in octopamine levels. "JH is suspected because it's found in the same cells, the same areas, as octopamine," says Bertino. "It's one of a number of options, but certainly one of the most promising."
While many biological systems differ sharply from, or have no counterpart in, systems in humans, Bertino points out that the transformation from tyrosine to octopamine strongly resembles the human process responsible for making dopamine and norepinephrine. "Dopamine and norepinephrine are not just any two hormones," enthuses Bertino, "they're critical." Indeed, both are key neurotransmitters in the human nervous system. Dopamine alone is responsible for aspects of movement, frontal lobe cognition and creative drive. In addition, dopamine is known as "nature's drug" for its role in transmitting pleasure impulses to the brain. Many drugs have their effects because they are structurally similar to dopamine. People with imbalances in their levels of dopamine and norepinephrine suffer from Parkinson's disease, schizophrenia, bipolar disorder, ADHD and various forms of dementia.
It's obvious Bertino is deeply invested in her research. She says she hopes to continue working with Lehman this coming year and plans on going to graduate school to study neuroscience. She explains that part of her expertise in the processes used for this project came from her extensive background; she has already taken a 300-level Cell Neurobiology course with Lehman that she says familiarized her with much of the equipment and techniques. Bertino's command of material and lab technique reveals an ability to execute detail, an essential element she brings to her role as Hamilton's sailing team captain. In addition, Bertino is proud to be a member of the BioMatters Club, a group of students who coordinate speakers, trips and on-campus events to expose Hamilton students to the field of biology.
-- by Elijah Lachance '10
Bertino skillfully pins her bee and extracts the brain with several seconds to spare. She performs the act calmly; she's done this hundreds of times. Nevertheless, she takes all the care of a cardiologist during an open-heart surgery. "Every brain is precious," she explains. "I don't want to waste any." Bertino points out that not all bees are the same. "The bee I just finished with was a forager. A bee starts as a nurse, working around the hive, and then gradually becomes a soldier, working the edges. Finally, it becomes a forager and flies out to find food for the community." As the bees progress from being nurses to foragers, the levels of a key enzyme, called octopamine, increase. One of the main objects of Bertino's project is to attempt to discover a correlation between the increase of octopamine in the bee brains and an increase in another enzyme or enzymes within the bees over the progression of the life cycle. It's more difficult than it might seem.
"Originally," says Bertino, "people thought that tyramine beta-hydroxylase (TBH) was the enzyme in charge, since TBH is the enzyme that is closest to octopamine in the progression along the pathway by which octopamine is formed from tyrosine, but the levels of TBH don't increase in foragers." Using a complex system of gels (which separate proteins by size), Western blots (modified gels), polymerase chain reactions (PCR) and various enzymes that cut, replicate or alter DNA, Bertino is now trying to discover if levels of another major player in the bee's brain, juvenile hormone (JH), significantly rise or lower in the transition from nurse to forager and whether that change could be linked to, or causing, the rise in octopamine levels. "JH is suspected because it's found in the same cells, the same areas, as octopamine," says Bertino. "It's one of a number of options, but certainly one of the most promising."
While many biological systems differ sharply from, or have no counterpart in, systems in humans, Bertino points out that the transformation from tyrosine to octopamine strongly resembles the human process responsible for making dopamine and norepinephrine. "Dopamine and norepinephrine are not just any two hormones," enthuses Bertino, "they're critical." Indeed, both are key neurotransmitters in the human nervous system. Dopamine alone is responsible for aspects of movement, frontal lobe cognition and creative drive. In addition, dopamine is known as "nature's drug" for its role in transmitting pleasure impulses to the brain. Many drugs have their effects because they are structurally similar to dopamine. People with imbalances in their levels of dopamine and norepinephrine suffer from Parkinson's disease, schizophrenia, bipolar disorder, ADHD and various forms of dementia.
It's obvious Bertino is deeply invested in her research. She says she hopes to continue working with Lehman this coming year and plans on going to graduate school to study neuroscience. She explains that part of her expertise in the processes used for this project came from her extensive background; she has already taken a 300-level Cell Neurobiology course with Lehman that she says familiarized her with much of the equipment and techniques. Bertino's command of material and lab technique reveals an ability to execute detail, an essential element she brings to her role as Hamilton's sailing team captain. In addition, Bertino is proud to be a member of the BioMatters Club, a group of students who coordinate speakers, trips and on-campus events to expose Hamilton students to the field of biology.
-- by Elijah Lachance '10
