- Angela Asirvatham, B.V.Sc.. Ph.D.
- Grace Chen, Ph.D
- Larry Corpus, Ph.D.
- Frank DiPino Jr., Ph.D.
- Barbara McCraith, Ph.D.
- Anthony Serino, Ph.D.
- Cosima Wiese, Ph.D.
- Colby Tanner, Ph.D.
Angela Asirvatham, B.V.Sc.. Ph.D.
Chairperson of the Biology Department & Associate Professor of Biology
Phone: (570) 674-8002
Grace Chen, Ph.D.
Larry Corpus, Ph.D.
Frank DiPino Jr., Ph.D.
Professor of Biology
Phone: (570) 674-6457
Barbara McCraith, Ph.D.
Associate Professor of Biology
Phone: Phone: (570) 674-6359
Anthony Serino, Ph.D.
Associate Professor of Biology
Cosima Wiese, Ph.D.
Associate Professor of Biology
Colby Tanner, Ph.D.
Assistant Professor of Biology
Ph.D. - Kent State University, Kent, OH
M.S. - University of Wyoming, Laramie, WY
B.V.Sc - Madras Veterinary College, Tamilnadu, India
Research Focus: Cell Signal Transduction
Research interest and goals: My research interests are primarily focused on A-kinase anchoring proteins (AKAPs) that play an important role in anchoring protein kinase A in various organelles of the cell. Protein kinase A is a broad spectrum kinase that binds cyclic AMP, the universal second messenger in the cell. I am currently interested in the role of A-kinase anchoring protein in Schwann cell proliferation. Schwann cells myelinate the peripheral neurons and myelin is important for rapid conduction of nerve impulses. Treatment of neonatal rat Schwann cells with heregulin (a growth factor secreted by neurons) and forskolin (a pharmacological agent that stimulates the cAMP pathway) results in a synergistic proliferative response. I have found that AKAPs are involved in this synergistic response. Investigation of signaling pathways that stimulate Schwann cell proliferation has important applications for demyelinating disorders such as multiple sclerosis and nerve injuries in the peripheral nervous system.
Current research in progress: Preliminary studies on heregulin/cAMP-mediated Schwann cell proliferation reveal that growth is inhibited when A-kinase anchoring proteins (AKAPs) of the cAMP signaling pathway are selectively knocked out using SiRNA (small interfering RNA) technology. Protein analysis of Schwann cells transfected with AKAP-SiRNA also revealed a reduction in Akt/Protein kinase B, a serine/threonine kinase that promotes cell survival. These studies indicate a crucial role for AKAPs and Akt in heregulin/cAMP-mediated Schwann cell growth. To determine if there was an association between the expression of AKAPs and phosphorylation of Akt, Schwann cells were stimulated with heregulin and forskolin and assayed for the expression of phosphorylated-Akt vs Akt. Mitogen-stimulated Schwann cells exhibited a decrease in the expression of both AKAPs, but an increase in phosphorylation of Akt. These preliminary observations suggest that a relationship between expression of AKAP proteins and phosphorylation of Akt may be necessary to mediate Schwann cell proliferation when stimulated with heregulin and forskolin.
Long-term goals of the project are to examine the role of the various AKAPs, their interacting partners and the role of phosphodiesterases in regulating Schwann cell proliferation. As AKAPs are known to interact with phosphodiesterases, this will provide key information regarding the regulation of various substrates in the cAMP-PKA-AKAP signaling pathway.
Ph.D. - Plant Biology and Ecology, Evolutionary Biology, and Behavior, Michigan State University
M.S. - Biology, University of Missouri-St. Louis
B.S. - Biology, National Cheng Kung University
Research Focus: Evolutionary Ecology
My research interests are in the field of evolutionary ecology and more specifically in local adaptation, speciation, plant-animal interactions, and biodiversity. My research focuses on how ecological factors result in the diversification of traits which lead to adaptation and speciation. I have been studying a group of understory herbaceous plants, Costus, in the Neotropical rainforest in Panama. I examined how these plants locally adapt to their abiotic (e.g., soil moisture and light availability) and biotic (e.g., pollination and herbivory) environmental factors and how the adaptations cause reproductive isolation between closely related species.
Current research in progress:
- I examine the strength of ecogeographic isolation across the genus Costus phylogenetically by using georeferenced locality data of herbarium specimens and spatial data on climatic variables in Geographic Information System (GIS). This study will enhance our understanding of how important ecogeographic isolation is in the diversification of Costus and how spatial variation of environmental factors contributes to adaptation and speciation of these plants.
- My previous research showed that Costus allenii and C. villosissimus have significant differences in the timing of seed germination and seedling survival when reciprocally transplanted in their distinct natural habitats. A new growth chamber experiment will be conducted to determine the environmental cues used by the seeds to determine their germination timing. This project will involve field trips to Panama for seed collection (and for FUN). Contact me if you are interested or stay tuned for more updates.
- I am developing a new project that will be carried out right here in Pennsylvania! There are three species of Allium that are native to Pennsylvania and they differ in the number of flower: 1-10 flowers for a typical A. canadense var. canadense inflorescence, 8-35 flowers for an A. cernuum inflorescence, and 6-50 flowers for an A. tricoccum inflorescence. With such a great the variation in flower numbers within species and among species, I will develop field and growth chamber projects to examine the effects of flower number on 1) pollinator visitation rate, 2) selfing rate, 3) the degrees of self-compatibility and 4) the degree of inbreeding depression.
- I have recently proposed a new approach to unify the existing methods of calculating reproductive isolation (Sobel and Chen 2014). This approach enables researchers to compare the relative contribution of barriers within and across study systems and to study patterns of speciation in a comparative context. I am now reevaluating the existing plant speciation literatures and quantifying the importance of temporal isolation (isolation due to differences in flowering time) in different latitudinal regions. I am inviting students who are interested in flowering time, literature search, and/or mathematics to participate in this project.
Ph.D. Entomology ~ Kansas State University
M.S. Entomology ~ Washington State University
M.A. Biology ~ CSU Sacramento
B.A. Biology ~ CSU Sacramento
Invertebrate Taxonomy and Biology
Research interests: All arthropods, especially insects found in streams, ponds, vernal pools, and seepages; parasitic arthropods, especially flies and other disease vectors.
Title of current research project (s):
1. The Dolichopodidae of NEPA.
2. Aquatic macroinvertebrates of Trout Brook, Luzerne Co., PA
1. Dolichopodids, commonly known as long-legged flies, are an essential component of most semi-aquatic ecosystems. No research has been done in NEPA to elucidate their presence, distribution, and role in the ecosystem. Adults are being collected and preserved periodically in order to determine what species are present in NEPA.
2. To establish a reference database of the aquatic macroinvertebrates present in Trout Brook, collections were made once per month from four sites over a 12-month period. All collected organisms were hand-sorted in the laboratory and preserved. Physiochemical data were taken twice monthly and included water temperature, conductivity, pH, alkalinity, oxygen, flow velocity, phosphates, and ammonia.
Ph.D. - Molecular Biology, Marquette University
BA - Zoology, State University of New York at Oswego
Molecular and cellular interactions of peripheral neurons and Schwann Cells.
Ph.D. - University of South Carolina
M.S. - Winthrop College
M.S. Ed. - State University of New York at Oneonta
B.S. - LeMoyne College
Bioturbation, salt marsh and esutarine biogeochemistry
Ph.D. - Physiology, Penn State University
M.S. - Biochemistry, University of Scranton
B.S. - Biology, University of Scranton
Physiology and Histology
Director, Clinical Laboratory Science Program
Research Interests: Neuro-muscular physiology, Physiology (human and animal), Cadaver correlation studies, and Aging.
Correlation Data Using Human Cadavers
Human cadavers are used each year in anatomy labs. These specimens contain a wealth of biomedical data that could be collected without interfering with the cadaver's primary purpose in teaching. Most of this data could be used in correlation studies linking these parameters to disease processes, risk factors, surgical interventions, age effects, and genetics. It is suggested that a concerted effort be attempted to utilize this resource to create this data base.
Possible correlation study data to be collected:
i. Cadaver Log (Suggested Measurements)
1. Thickness of fat pads at substernal, hip (iliac), pubic sites
2. Thickness of coronary fat
3. Finger prints
4. Length of femur, humerus, tibia, etc.
5. Diameter of femur head, humeral head
6. Thickness of calvaria at frontal bone
7. Hip width, chest size
8. Number and size of plaques in key vessels (coronary, aorta, carotids)
9. Number of Senile Plaques
10. Number of polyps in colon
11. Outer Ear shape and structure
ii. Vital Stats: age, COD, race, Ht, Wt., etc.
iii. Surgical intervention inventory
iv. Pathology inventory (including histological studies)
v. Analyze DNA for genetic markers
Ph.D. - Pennsylvania State University
M.Sc. - Pennsylvania State University
B.A. - Biology & German, Bucknell University
Effects of atmospheric pollution on plant physiology and biochemisty; Investigation of mechanisms of plant
The focus of my research is on the effects of environmental stresses on plants and how plants respond to stress conditions, particularly to those stressors derived from human activities. The current project seeks to evaluate the impacts of acidic conditions on the aquatic plant duckweed (Lemna spp.).
Duckweed grows ubiquitously in freshwater ponds and lakes and is a food source for a variety of organisms in those communities. Even though duckweed has been used extensively as a model organism to investigate effects of water pollution on aquatic ecosystems, there is very little in the scientific literature that evaluates the effects of acidification on metabolic processes in duckweed. Some of the lakes in NE Pennsylvania are very acidic due to acid mine drainage and acidic precipitation, and I want to investigate whether acidic conditions impact growth and reproduction of this plant.
The goals for the work are as follows:
1. Impacts on growth and reproduction: characterize changes in quantity and activity of enzymes and metabolites associated with photosynthesis; characterize changes in gene expression in genes associated with photosynthesis
2. Impacts on plant stress and defense responses: characterize changes in quantity and activity of enzymes and metabolites associated with plant response to stress; characterize changes in gene expression in genes associated with plant response to stress
Duckweed can easily be grown in culture, and we have established protocols for maintaining duckweed cultures in aerated nutrient solution. To address our experimental questions, duckweed plants are grown in acidified nutrient solution in an environmental chamber with a 16 hr photoperiod for 14 days.
Data from initial experiments show that duckweed growth and asexual reproduction are negatively impacted by exposure to acidic conditions. As plants use the process of photosynthesis to acquire the energy necessary for growth and reproduction, any decreases in photosynthesis as a result of environmental stress would be directly correlated with reduced growth and reproduction. Additional experiments are currently being conducted to better understand the impacts of acidic conditions on photosynthesis, and we have already developed the protocols necessary to carry out these experiments:
Impacts on Photosynthesis:
1. Results from initial experiments showed that duckweed fronds grown in acidic conditions were a lighter color green than the control fronds. Current experiments are underway in which duckweed tissue samples are being extracted for quantification of chlorophyll a and b and total chlorophyll.
2. Impacts on chlorophyll synthesis will be measured by determining the abundance of mRNA abundance of the chlorophyll synthase gene. Chlorophyll synthase catalyzes the last step in the synthesis of both chlorophyll a and b; any changes in transcript abundance could be related to
changes in chlorophyll quantity. These findings would demonstrate whether changes in chlorophyll quantity result from either differential synthesis or breakdown of the chlorophyll pigment.
3. Impacts on Rubisco will be measured by quantifying Rubisco protein as part of total soluble leaf protein. Rubisco (Ribulose-1,5-bisphosphate carboxylase oxygenase) fixes atmospheric CO2 as the first step in synthesizing carbohydrates in photosynthesis and comprises 50-70% of total soluble leaf protein. Any changes in Rubisco quantity would have significant impacts on carbon metabolism as part of photosynthesis in plants.
Impacts on Plants Stress Responses:
1. Many types of stresses can generate oxygen radicals in plants, and plants respond to these stressors by up-regulating their antioxidant responses. Experiments are underway to determine whether exposure to acidic conditions increases the quantities of antioxidant metabolites in duckweed using the DPPH total antioxidant assay.
2. If the results of the total antioxidant assay reveal changes in total antioxidants in response to acidic pH conditions, duckweed tissue will be further analyzed to determine whether ascorbate, an abundant antioxidant metabolite in plants, plays a role in defending duckweed from oxidative stress generated by acidic conditions.
Education: B.A. University of Montana
Ph.D. University of Utah
Teaches: Structure and Function and Anatomy and Physiology
Research/Specialty: Animal Behavior, Urban Ecology and Biostatistics