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Faculty

Contact info and brief biography of our Biological Sciences faculty. 

See what degrees you can earn when you learn from these professors >

David Lindsey

Chair, Professor of Biology, Rosario Beach Marine Laboratory Director

(509) 527-2602
David.Lindsey@wallawalla.edu

 

Education

  • PhD University of Texas, 1992

Teaching Areas

General biology, journal club: cancer biology, cell biology III: genomics and regulation, molecular biological techniques and advanced microbiology

Research/Interests

Professor Lindsey explains his interests as quoted: "The transformation of a fertilized egg to a complex multicellular organism depends on a variety of mechanisms that control cell-cell communication and changes in gene expression. The selective destruction of specific proteins is one of the important mechanisms that control this developmental process. Many proteins are selectively degraded by the ubiquitin-dependent proteolytic pathway. In this pathway, linkage of a protein to ubiquitin targets the protein for degradation by the proteasome. Defects in this pathway have been implicated in a wide range of human disorders including tumor formation and neurodegenerative diseases.

We are interested in understanding the role of ubiquitin-dependent proteolytic pathways in multicellular development. We use the social amoebae Dictyostelium discoideum as a model system. It is a simple and elegant system to study fundamental developmental processes that are used by higher systems including growth-to-differentiation transitions, directed cell movement, cell-type determination, and formation of structures with specific size and shape. 

Dictyostelium normally exists as solitary cells that proliferate by cell division while feeding on bacteria in soil and decaying leaves. When stressed by starvation, these amoebae stop dividing and enter a developmental program that results in the formation of a multicellular fruiting body. The cells first aggregate into a mound which then elongates to form a slug that can migrate to a suitable location for fruiting body formation. Cells specified to become stalk cells, the prestalk cells, occupy the tip of the slug; the posterior region of the slug contains mostly prespore cells. Eventually, coordinated cell movements and additional differentiation events result in a fruiting body consisting of a mass of spore cells supported on a column of stalk cells. 
We have identified two enzymes that appear to function in ubiquitin-dependent proteolytic pathways and are required for Dictyostelium development: UbpA and RbrA. UbpA is a functional homolog of the yeast Ubp14 and human isopeptidase T, enzymes which appear to function in the disassembly of free ubiquitin chains following their use as tags for protein degradation. It is likely that these enzymes facilitate ubiquitin dependent proteolysis by preventing free ubiquitin chains from competing for substrate binding sites on the proteasome. Control of cellular ubiquitin chain levels by UbpA may provide a mechanism for modulating the rates of protein degradation by the proteasome during changing developmental conditions. We are currently investigating the role of UbpA at the growth-development transition by analyzing defects found in ubpA-deficient cells. Results from this work may elucidate molecular mechanisms that underlie the conversion of stem cells to differentiating cells. 

RbrA is a putative ubiquitin ligase that is required for cell-type proportioning and pattern formation. rbrA-deficient cells form slugs that are unable to phototax or develop into fruiting bodies. RbrA is highly similar to ariadne-like ubiquitin ligases, which are members of the RBR family. RBR family members are widespread in eukaryotes and include parkin, a gene implicated in Parkinson's disease. To delineate RbrA-dependent pathways, we are using genetic, molecular, and biochemical approaches to identify proteins that interact with RbrA."

Cecilia Brothers

Assistant Professor of Biology

(509) 527-2068
Cecilia.Brothers@wallawalla.edu

Education 

  • PhD University of Alabama at Birmingham, 2016

Teaching Areas

Anatomy and physiology, biostatistics and advanced microbiology 

Research/Interests 

Professor Brothers writes, "Research in my lab focuses on the physiology and ecology of marine invertebrates from coastal ecosystems, and the ability of these organisms to respond to climate change and other anthropogenic stressors."

Dr. Brothers' website >


David Cowles

Professor of Biology

(509) 527-2264
David.Cowles@wallawalla.edu

Education

  • PhD University of California, Santa Barbara, 1987; Aquatic and Population Biology 

Teaching Areas

General biology, plant biology, limnology, ecological physiology, marine biology, marine ecology and marine invertebrates

Research/Interests

Professor Cowles is interested in questions that involve animals' survival in the sea. Some projects he is currently involved in include:

  • What is causing algal blooms in Lake Crescent, a beautiful hyper-ologitrophic lake in Washington State
  • How Hemisquilla californiensis, an active burrow-dwelling stomatopod, survives under low oxygen conditions in its burrow 
  • The eyes and vision of H. californiensis, and colors it responds to 
  • Effects of pollution on the gene pools of marine invertebrate species
  • How closely related are individuals of the same deep-sea species which are separated by thousands of miles of ocean?
  • Swimming energetics and metabolism of a number of deep-sea midwater crustaceans
  • Vertical migration

Other research interests include ecological physiology, marine biology, physiology of marine species, both deep-sea and nearshore.

Dr. Cowles' website >

Jonathan Cowles

Adjunct Professor of Biology

(509) 527-2483
Jonathan.Cowles@wallawalla.edu

Teaching Areas

Contemporary biology, general ecology and anatomy and physiology


Janice McKenzie

Associate Professor of Biology

(509) 527-2424
Janice.McKenzie@wallawalla.edu

Education

  • PhD Purdue University, 2006; Biomedical Engineering

Teaching Areas

Anatomy and physiology and biological research

Research/Interests

  • Biotechnology: Upstream processing - DNA methods and analysis, Bioreactor technology; Downstream processing - Protein purification and characterization, Scale-up

  • Biomedical engineering: Biomaterials, Nanotechnology, Tissue engineering, Regenerative medicine 

Jim Nestler

Professor of Biology

(509) 527-2551
Jim.Nestler@wallawalla.edu

Education

  • PhD University of Colorado, Boulder, 1990; Environmental, Population, Organismic Biology 

Courses

General biology, biostatistics, scientific diving and natural history of vertebrates 

Research/Interests

Professor Nestler's research primarily focuses on the study of sea cucumbers. He is specifically interested in answering the following questions through research:

  • "Are sea cucumbers really important? Do they provide any particular function(s) in the marine environment? Who cares if they all get eaten and disappear?"
  • "Why do some sea cucumbers lose all of their internal organs in the winter, only to regrow them a month or two later?"

Dr. Nestler’s website >


Kirt Onthank

Associate Professor of Biology

(509) 527-2642
Kirt.Onthank@wallawalla.edu

Education

  • PhD Washington State University, 2013

Courses

Biological research, cell biology I: structure and bioenergetics, biocomputing and bioinformatics and animal physiology

Research/Interests

  • Research interests include ecological physiology and behavioral ecology of marine invertebrates, especially cephalopods. 
  • His current research is focused around the idea that all living things must bring to bear specific physiological adaptations to survive and thrive in the environments in which they find themselves.  He is particularly interested in how cephalopods' physiology, which is similar to that of slugs, snails and clams, has enabled this group of marine invertebrates to be active, mobile predators that compete with vertebrates.  He is also interested in adaptations, behavioral and physiological to dynamic, changing environments, such as hydrothermal vents.

Dr. Onthank's website >

Joan Redd

Professor of Biology, Biology Graduate Program

(509) 527-2482
Joan.Redd@wallawalla.edu

Education

  • PhD University of Denver, 1989

Teaching Areas

Microbiology, genetics and molecular biology, genetics, immunology and ethics issues in science

Research/Interests

Professor Reed's research interests include tumor immunology, hybridoma production, and dietary supplements of immune function.

Last update on November 14, 2018