Steven J. Pittler, Ph.D.

Department of Vision Sciences

Pittler

Steven Jay Pittler, Ph.D.
Professor, Vision Sciences

Contact Information:
Office - (205) 934-6744

Physical Address:
Volker Hall 375B
1670 University Blvd.

Mailing Address:
VH 375B 
1720 Second Avenue South 
Birmingham, AL 35924

Education

B.S. – Michigan State University

Ph.D. – Michigan State University

Postdoctoral – Baylor College of Medicine

 

Administrative Responsibilities:

Director, Vision Science Research Center

Co-Director, Vision Science Research Center, Molecular and Cellular Analysis Core Module

Chair, Vision Sciences Graduate Program Curriculum Committee

PI, P30 Core Grant

 

Secondary Appointments:

Professor, Ophthalmology

Professor, Biochemistry and Molecular Genetics

Senior Scientist, Vision Science Research Center

Senior Scientist, Arthritis and Musculoskeletal Disease Center

Senior Scientist, Center for Biophysical Sciences and Engineering

Member, Medical Scientist Training Program

Scholarly Activity:

Teaching –

VIS 745 - Biology and pathology of the Posterior Segment.  This course provides a solid background and understanding of the structure and function of the posterior segment from optic nerve to ora serrata.  Dr. Pittler is the Course Director.

VS 111 - Biochemistry of the Eye. This course covers the Biochemistry and Molecular Biology of the Eye geared towards the needs of the professional Optometry student. Dr. Pittler is co-Course Director with Dr. Alecia Gross.

OPVS 111 - Basic Science and Clinical Optometry.  This course emphasizes the importance of the basic science courses by showing connections between clinical optometric conditions and the underlying basic sciences. Dr. Pittler particiates in two lectures on retinitis pigmentosa with Dr. Rod Nowakowski in this course.

OBHS 111 - Fundamentals of Dentistry and Optometry I.  This is a composite course that primarily deals with the biochemical and genetic principles of human biology. Dr. Pittler gives 5 lectures in Genetics in this course.

Research –

Research in Dr. Pittler’s laboratory focuses on the biochemistry and molecular biology of photoreceptor cells. Within these cells the initial events mediating vision occur. Light is absorbed in the photoreceptors by the receptor molecule, rhodopsin which then activates another protein, transducin. Transducin activates a third protein, cGMP phosphodiesterase (PDE) that leads to the hydrolysis of cyclic guanosine monophosphate (cGMP). The drop in cGMP levels closes a cGMP-gated cation channel in the plasma membrane triggering the formation of an electrical impulse that is transmitted to the brain. Guanylate cyclase mediates the return to the dark state by replenishing the cGMP levels. Other ancillary proteins regulate the system to allow a response over 8 orders of magnitude of light intensity. 

Pittler Mouse RetinaThe retina is comprised of several tightly arranged layers of cells; the ganglion cell layer (GCL) is oriented towards the center of the eye. These cells have long axons that traverse the retina and extend to the brain. The inner plexiform layer (IPL) consists of synaptic connections between ganglion cells and inner retinal neurons and the outer plexiform layer (OPL) consists of synaptic connectionsbetween bipolar and photoreceptor cells. The inner nuclear layer (INL) consists of the nuclei of the inner retinal cells. The photoreceptor inner segments (RIS) contain all of the housekeeping machineryof the photoreceptors The phototransduction process that initiates vision is active exclusively in the photoreceptor outer segments (ROS). 

The primary focus in my laboratory is on the biochemistry, cell biology and molecular biology of the cGMP-gated cation channel of the rod photoreceptor. This channel consists of two related subunits (alpha and beta) in a tetrameric complex consisting of 1 beta and 3 alpha subunits. The beta subunit appears to be a modulatory subunit of the activity that is observed with the alpha subunit alone. We are focusing on the beta subunit gene which is very complex encoding multiple transcripts that are likely to be initiated by multiple promoters. We have generated a knockout of the gene in mice and have found that the beta subunit is required for normal functional expression of the channel and that both the beta subunit and a related GARP protein expressed from the same gene are required for normal disk morphogenesis and outer segment structural integrity. We are currently working on further characterization of the structural roles of the beta subunit and GARP proteins. 

Publications:

 

 

Additional Information:

Previous Positions:

Baylor College of Medicine - Research Instructor 1991-1992

University of South Alabama - Assistant, Associate Professor of Biochemistry & Molecular Biology 1992-1999

University of South Alabama - Director, Center for Eye Research 1995-1999