Cell Biology and Genetics :: Research Interests

Faculty Research Interests

John Aschenbrenner , Ph.D.
Associate Professor

Dr.Aschenbrenner's primary research interest involves collaborating on clinical research projects. He has contributed his expertise as an anatomist to projects in orthopedics, gynecology/obstetrics, emergency medicine and advanced concepts in manipulative medicine

Patrick Cammarata , Ph.D.
Professor

Mechanism(s) of ocular diabetic complications, including sugar cataract development. Inositol lipid metabolism, myo-inositol uptake and efflux, molecular cloning, fine structure analysis of the sodium/myo-inositol cotransporter gene, promotes characterization and transcriptional regulation of the sodium/myo-inositol cotransporter gene. (Category III)

Abbott Clark , Ph.D.
Professor and Director of Visual Sciences Program

Dr. Clark’s research interests are focused on understanding the biochemical, cellular and molecular mechanisms involved in the pathobiology of glaucoma. Dr. Clark and his collaborators have discovered glaucoma associated genes and glaucomatous pathogenic pathways using molecular genetics, differential gene expression, proteomics, ocular cell culture, ex vivo organ culture, and rodent models of glaucoma.

Ignacy Gryczynski , Ph.D.
Professor and Director of the Microscopy Core Facility, Cell Biology and Genetics & Molecular Biology and Immunology

Fluorescence spectroscopy and its applications in biochemistry and biology. Dr. Gryczynski's research focuses on fluorescence enhancements near metallic surfaces and particles. The enhanced fluorescence is being applied to sensing devices and bioassays.

Yi Wei Jiang , Ph.D.
Associate Professor

Dr. Jaing's main research interest is in the functions and mechanisms of over-production of non-translatable mRNA

Non-translatable mRNA has been regarded as neutral or inconsequential in terms of intracellular signal transduction. Using the budding yeast S. cerevisiae as a model organism, we have discovered that over-production of non-translatable mRNA hyper-stimulates the highly conserved TOR pathway to regulate global cellular activities such as cell cycle and transcription. We are using a variety of experimental tools (genetic, genomic, molecular and biochemical) to study the biological functions of over-production of non-translatable mRNA and the underlying mechanisms.

Research Area 2: Slowed DNA synthesis-induced filamentous
differentiation of S. cerevisiae

A key question in eukaryotic differentiation is whether there are common regulators or biochemical events that are required for diverse types of differentiation or whether there is a core mechanism for differentiation. The unicellular model organism S. cerevisiae undergoes filamentous differentiation in response to environmental cues. Since conserved cell cycle regulators, the mitotic cyclin-dependent kinase Clb2/Cdc28 and its inhibitor Swe1, were found to be involved in both nitrogen starvation- and short chain alcohol-induced filamentous differentiation, they were identified as components of the core mechanism for filamentous differentiation. We have discovered that slowed DNA synthesis also induces yeast filamentous differentiation through conserved checkpoint proteins Mec1 and Rad53. The mechanism for Rad53 activation in filamentation is distinct from the classic phosphorylation by Mec1 in response to DNA damage or replication block. Swe1 and Clb2 are also involved in this form of differentiation, and the core status of Swe1/Clb2/Cdc28 in the mechanism of filamentous differentiation has therefore been confirmed. Slowed DNA synthesis also induces differentiation in mammalian cancer cells, and such stimulus conservation may indicate that the core mechanism for yeast filamentous differentiation is conserved in mammalian differentiation. Therefore, yeast filamentous differentiation may be an excellent model for cancer development and therapeutics. The human homologues of MEC1 and RAD53 (ATM/ATR and CHK2 respectively) are indeed known tumor suppressor genes. Our studies of yeast differentiation may help shed light on human cancer development and the discovery of novel anticancer drugs.

Rustin Reeves , Ph.D.
Associate Professor

Current interests include introduction of multimedia into new medical and graduate curricula, with an emphasis on web-supported educational materials. These activities include the development of digital images of anatomical and histological structures for use as study, testing and instructional materials in the medical, graduate and physician assistant programs. Additional interests include the development of web-based courses in the anatomical science for use by graduate and medical (or premedical) students interested in these subject areas. (Category II)

Rouel Roque , M.D.
Adjunct Associate Professor

The research program focuses on the cellular and molecular events during apoptotic cell death and the role of adult stem cells in regeneration or repair of degenerative retinal diseases and of cardiovascular disorders. Specific interests are on the cellular and molecular mechanisms modulating neuronal and retinal photoreceptor development and survival, specifically the role of supporting cells (microglia, retinal pigment epithelium, and Muller glia) and of neurotrophic factors/receptors (proneurotrophins and the p75 neurotrophin receptor). In the heart, ongoing studies include isolation and characterization, and establishment of in vitro models of adult cardiac stem cells to study differentiation, apoptosis, and repair mechanisms during ischemia or oxidative damage to the heart. Cell signaling pathways involving oxidative stress, MAP-Kinases, protein phosphatases, and heat shock proteins in the differentiation of neuronal and cardiac stem cells are major interests in the laboratory. Interests in cancer research are directed towards development of DNA vaccines and anti-cancer drugs, and identification of cancer stem cell markers.

Armando Rosales , M.D.
Assistant Professor

Medical Education

Harold Sheedlo , Ph.D.
Assistant Professor

The main focus of my research is to develop and characterize photoreceptor cell lines stimulated by factors secreted retinal pigment epithelial (RPE) cells. Following characterization and identification, these cells will be transplanted into diseased rodent retinas. RPE cells have several functions including secretion of growth factors, neurotrophins and cytokines and phagocytosis of shed outer segments of photoreceptor cells. Progenitor cells have been isolated from neonatal rat retinal explants grown in the presence of proteins secreted by RPE cells. Populations of these progenitor cells have been virally transformed and are currently being characterized by in vitroassays, electrophoresis, immunocytochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). The transformed progeitor cells will be grown in the presence of neurotrophins and known growth factors to direct these cells to a photoreceptor cell fate. Populations of progenitor cells from embryonic, neonatal and adult retinas will be cultured, passaged and frozen in liquid nitrogen for future studies of cellular differentiation. The photoreceptor cells derived from transformed progenitor cell populations will be transplanted into diseased rodent eyes and their functional capacity will be assessed by microscopic and visual tests. The results of these studies will provide evidence for the feasibility of similarly-developed human photoreceptor cell lines and subsequent transplantation in diseased eyes of patients suffering from age-related macular degeneration (ARMD) and retinitis pigmentosa (RP). Human retinal explants grown in proteins of RPE cells have been stimulated to generate progenitor cells; thus, the first step toward developing a transformed human progenitor cell and extended in vivo and in vitro investigations has been accomplished. (Category III)

Wolfram Siede , Ph.D.
Associate Professor

Current projects are aimed at understanding cellular regulation responses following DNA damage, using yeast as a model. It is known that genetic stability is preserved by cell cycle arrest accompanied by regulation of DNA repair enzymes. We are studying the molecular mechanisms of DNA damage recognition that activate these responses. We are also involved in elucidating the regulation of damage-bypass polymerases that result in DNA damage tolerance. Such research is important for understanding the mutator phenotype of cancer cells. The conservation of basic mechanisms makes yeast an attractive model and we are also exploring ways of using yeast for screening and characterization of novel anti-cancer drugs

Joseph Warren , PhD
Assistant Professor and Assistant Director, DNA Identity Laboratory; Assistant Professor, Cell Biology and Genetics

DNA Repair Mechanisms and their use in Forensic Biology non- human DNA typing application of Whole genome Amplification on Forensic Biology mutation rates of mitochondrial DNA SNPs in Forenisc Biology Legal Aspects of Forensic Biology

Robert Wordinger , Ph.D.
Professor and Chairman

Glaucoma is a leading cause of blindness worldwide and is characterized by a defect in the ability of aqueous humor to drain efficiently through the trabecular meshwork. This abnormality results in elevated intraocular pressure resulting in death of retinal ganglion cells and subsequent blindness. Our laboratory studies gene and protein expression of growth factors and neurotrophins by human trabecular meshwork cells and cells of the human optic nerve head. We wish to understand the role these factors play normally and in the pathophysiology of glaucoma. Modern cell and molecular biology techniques are utilized by graduate students and research associates. Ultimately we wish to discover new and innovative methodoligies for the diagnosis, management and treatment of glaucoma (Catagory III)


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Faculty Research Interests John Aschenbrenner , Ph.D. Associate Professor Dr.Aschenbrenner's primary research interest involves collaborating on clinical research projects. He has contributed his expertise as an anatomist to projects in orthopedics, gynecology/obstetrics, emergency medicine and advanced concepts in manipulative medicine Patrick Cammarata , Ph.D. Professor Mechanism(s) of ocular diabetic complications, including sugar cataract development. Inositol lipid metabolism, myo-inositol uptake and efflux, molecular cloning, fine structure analysis of the sodium/myo-inositol cotransporter gene, promotes characterization and transcriptional regulation of the sodium/myo-inositol cotransporter gene. (Category III) Abbott Clark , Ph.D. Professor and Director of Visual Sciences Program Dr. Clark’s research interests are focused on understanding the biochemical, cellular and molecular mechanisms involved in the pathobiology of glaucoma. Dr. Clark and his collaborators have discovered glaucoma associated genes and glaucomatous pathogenic pathways using molecular genetics, differential gene expression, proteomics, ocular cell culture, ex vivo organ culture, and rodent models of glaucoma. Ignacy Gryczynski , Ph.D. Professor and Director of the Microscopy Core Facility, Cell Biology and Genetics & Molecular Biology and Immunology Fluorescence spectroscopy and its applications in biochemistry and biology. Dr. Gryczynski's research focuses on fluorescence enhancements near metallic surfaces and particles. The enhanced fluorescence is being applied to sensing devices and bioassays. Yi Wei Jiang , Ph.D. Associate Professor Dr. Jaing's main research interest is in the functions and mechanisms of over-production of non-translatable mRNA Non-translatable mRNA has been regarded as neutral or inconsequential in terms of intracellular signal transduction. Using the budding yeast S. cerevisiae as a model organism, we have discovered that over-production of non-translatable mRNA hyper-stimulates the highly conserved TOR pathway to regulate global cellular activities such as cell cycle and transcription. We are using a variety of experimental tools (genetic, genomic, molecular and biochemical) to study the biological functions of over-production of non-translatable mRNA and the underlying mechanisms. Research Area 2: Slowed DNA synthesis-induced filamentous differentiation of S. cerevisiae A key question in eukaryotic differentiation is whether there are common regulators or biochemical events that are required for diverse types of differentiation or whether there is a core mechanism for differentiation. The unicellular model organism S. cerevisiae undergoes filamentous differentiation in response to environmental cues. Since conserved cell cycle regulators, the mitotic cyclin-dependent kinase Clb2/Cdc28 and its inhibitor Swe1, were found to be involved in both nitrogen starvation- and short chain alcohol-induced filamentous differentiation, they were identified as components of the core mechanism for filamentous differentiation. We have discovered that slowed DNA synthesis also induces yeast filamentous differentiation through conserved checkpoint proteins Mec1 and Rad53. The mechanism for Rad53 activation in filamentation is distinct from the classic phosphorylation by Mec1 in response to DNA damage or replication block. Swe1 and Clb2 are also involved in this form of differentiation, and the core status of Swe1/Clb2/Cdc28 in the mechanism of filamentous differentiation has therefore been confirmed. Slowed DNA synthesis also induces differentiation in mammalian cancer cells, and such stimulus conservation may indicate that the core mechanism for yeast filamentous differentiation is conserved in mammalian differentiation. Therefore, yeast filamentous differentiation may be an excellent model for cancer development and therapeutics. The human homologues of MEC1 and RAD53 (ATM/ATR and CHK2 respectively) are indeed known tumor suppressor genes. Our studies of yeast differentiation may help shed light on human cancer development and the discovery of novel anticancer drugs. Rustin Reeves , Ph.D. Associate Professor Current interests include introduction of multimedia into new medical and graduate curricula, with an emphasis on web-supported educational materials. These activities include the development of digital images of anatomical and histological structures for use as study, testing and instructional materials in the medical, graduate and physician assistant programs. Additional interests include the development of web-based courses in the anatomical science for use by graduate and medical (or premedical) students interested in these subject areas. (Category II) Rouel Roque , M.D. Adjunct Associate Professor The research program focuses on the cellular and molecular events during apoptotic cell death and the role of adult stem cells in regeneration or repair of degenerative retinal diseases and of cardiovascular disorders. Specific interests are on the cellular and molecular mechanisms modulating neuronal and retinal photoreceptor development and survival, specifically the role of supporting cells (microglia, retinal pigment epithelium, and Muller glia) and of neurotrophic factors/receptors (proneurotrophins and the p75 neurotrophin receptor). In the heart, ongoing studies include isolation and characterization, and establishment of in vitro models of adult cardiac stem cells to study differentiation, apoptosis, and repair mechanisms during ischemia or oxidative damage to the heart. Cell signaling pathways involving oxidative stress, MAP-Kinases, protein phosphatases, and heat shock proteins in the differentiation of neuronal and cardiac stem cells are major interests in the laboratory. Interests in cancer research are directed towards development of DNA vaccines and anti-cancer drugs, and identification of cancer stem cell markers. Armando Rosales , M.D. Assistant Professor Medical Education Harold Sheedlo , Ph.D. Assistant Professor The main focus of my research is to develop and characterize photoreceptor cell lines stimulated by factors secreted retinal pigment epithelial (RPE) cells. Following characterization and identification, these cells will be transplanted into diseased rodent retinas. RPE cells have several functions including secretion of growth factors, neurotrophins and cytokines and phagocytosis of shed outer segments of photoreceptor cells. Progenitor cells have been isolated from neonatal rat retinal explants grown in the presence of proteins secreted by RPE cells. Populations of these progenitor cells have been virally transformed and are currently being characterized by in vitroassays, electrophoresis, immunocytochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). The transformed progeitor cells will be grown in the presence of neurotrophins and known growth factors to direct these cells to a photoreceptor cell fate. Populations of progenitor cells from embryonic, neonatal and adult retinas will be cultured, passaged and frozen in liquid nitrogen for future studies of cellular differentiation. The photoreceptor cells derived from transformed progenitor cell populations will be transplanted into diseased rodent eyes and their functional capacity will be assessed by microscopic and visual tests. The results of these studies will provide evidence for the feasibility of similarly-developed human photoreceptor cell lines and subsequent transplantation in diseased eyes of patients suffering from age-related macular degeneration (ARMD) and retinitis pigmentosa (RP). Human retinal explants grown in proteins of RPE cells have been stimulated to generate progenitor cells; thus, the first step toward developing a transformed human progenitor cell and extended in vivo and in vitro investigations has been accomplished. (Category III) Wolfram Siede , Ph.D. Associate Professor Current projects are aimed at understanding cellular regulation responses following DNA damage, using yeast as a model. It is known that genetic stability is preserved by cell cycle arrest accompanied by regulation of DNA repair enzymes. We are studying the molecular mechanisms of DNA damage recognition that activate these responses. We are also involved in elucidating the regulation of damage-bypass polymerases that result in DNA damage tolerance. Such research is important for understanding the mutator phenotype of cancer cells. The conservation of basic mechanisms makes yeast an attractive model and we are also exploring ways of using yeast for screening and characterization of novel anti-cancer drugs Joseph Warren , PhD Assistant Professor and Assistant Director, DNA Identity Laboratory; Assistant Professor, Cell Biology and Genetics DNA Repair Mechanisms and their use in Forensic Biology non- human DNA typing application of Whole genome Amplification on Forensic Biology mutation rates of mitochondrial DNA SNPs in Forenisc Biology Legal Aspects of Forensic Biology Robert Wordinger , Ph.D. Professor and Chairman Glaucoma is a leading cause of blindness worldwide and is characterized by a defect in the ability of aqueous humor to drain efficiently through the trabecular meshwork. This abnormality results in elevated intraocular pressure resulting in death of retinal ganglion cells and subsequent blindness. Our laboratory studies gene and protein expression of growth factors and neurotrophins by human trabecular meshwork cells and cells of the human optic nerve head. We wish to understand the role these factors play normally and in the pathophysiology of glaucoma. Modern cell and molecular biology techniques are utilized by graduate students and research associates. Ultimately we wish to discover new and innovative methodoligies for the diagnosis, management and treatment of glaucoma (Catagory III)
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