The retinal rod photoreceptor is a
highly polarized postmitotic cell type responsible for the initial
events in phototransduction. The outer segment portion of the
rod cell encloses densely packed, closed, flattened membranous
sacs referred to as disks which are stacked along the length of
the outer segment. The continuous processes of disk membrane formation
and shedding maintains the ROS at a constant length. The primary
focus of the work in this laboratory involves the characterization
of a fundamental cellular process, membrane fusion in maintaining
the structural integrity of the rod cell. To this end both promoters
of membrane fusion such as phospholipase induced membrane destablilizations
(as measured by 31P NMR) and fusion inhibitors such as cytoskeletal
proteins are being studied. It is essential that in order to maintain
its structural integrity, thereby function effectively, the ROS
must not undergo indiscriminate membrane fusion. At the same time,
membrane fusion events are necessary in the formation of new disks
from the plasma membrane and the phagocytosis of old disks by
the pigment epithelium. Thus by focusing on both the promoters
and inhibitors of ROS membrane fusion we can begin to determine
the regulatory elements in this process.
Recent Grant Support
Zeigler Foundation - E. Matilda Zeigler Award 2000-2003
National Eye Institute - P.I.
"Membrane Fusion in Retinal Rod Outer Segments" 1994 - 2003
K. Boesze-Battaglia, F. P. Stefano, M. Fenner, A. A. Napoli, Jr., A peptide analogue to a fusion domain within photoreceptor peripherin/rds promotes membrane adhesion and depolarization. Biochimica et Biophysica Acta 1463 343-354. 2000.
Boesze-Battaglia, K. , and Schimmel, R. Collagen-Stimulated Unidirectional Translocation of Cholesterol in Human Platelet Membranes. J. Exp. Biology, 202, 453-460. 1999.
Boesze-Battaglia, K., Lamba, O.P., Napoli, A., Sinha, S & Guo, Y. Fusion between Retinal Rod Outer Segment Membranes and Model Membranes: A Role for Photoreceptor Peripherin/rds. Biochemistry 37, 26 9477-9487. (1998)
Boesze-Battaglia, K. and Allen, C. Differential Rhodopsin Regeneration In Photoreceptor Membranes is Correlated with Variations in Membrane Properties. Bioscience Reports, Vol. 18, No. 1 (1998)
K. Boesze-Battaglia, and R. J. Schimmel. Cell Membrane Lipid Composition and Distribution: Implications for Cell Function and Lessons Learned from Photoreceptors and Platelets. Review - Journal of Experimental Biology, 200, 2927-2936. 1997.
R. Schimmel, P. Shah, M. Fenner, K. Boesze-Battaglia. Cholesterol Enhances the Adhesion of Human Platelets to Fibrinogen: Studies Using a Novel Fluorescence Based Assay. Platelets (1997) 8, 261-267.
K. Boesze-Battaglia, F. Kong, O.P. Lamba, F.P. Stefano and David S. Williams. Purification and Light Dependent Phosphorylation of a Candidate Fusion Protein, Photoreceptor Peripherin/rds. Biochemistry, Vol. 36: 22, 6835-6846. 1997
K. Boesze-Battaglia. Spontaneous Fusion of Intracellular Rod Outer Segment Disk Membranes with the Surrounding Plasma Membrane. 1997, Invest. Ophtholmol. Vis. Sci. 38, 18-24
K. Boesze-Battaglia, S.T.Clayton and R.J. Schimmel. Cholesterol Redistribution Within Human Platelet Plasma Membrane: Evidence for a Stimulus Dependent Event. Biochemistry, 35, 6664-6673. 1996.
K. Boesze-Battaglia, A.D. Albert and P.L. Yeagle. Fusion Between Disk Membranes and Plasma Membrane of Bovine Photoreceptor Cells is Calcium Dependent. Biochemistry 31, 3733-3738. 1992.
K. Boesze-Battaglia, and A.D. Albert. Cholesterol Modulation of Phtotreceptor Function in Bovine Retinal Rod Outer Segments. J. Biol. Chem., 265, 20727-20730. 1990.
K.Boesze-Battaglia , S.J. Fliesler and A. Albert. Relationship of Cholesterol Content to Spatial Distribution and Age of Disk Membranes in Retinal Rod Outer Segments. J. Biol. Chem., 265, 18867-18870. 1990.
Boesze-Battaglia, K., T. Hennesey and A.D. Albert. Cholesterol Heterogeneity in Bovine Rod Outer Segment Disk Membranes. J. Biol. Chem. 264, 8151-8155. 1989.