The effects of heat-shock and differentiation on nuclear structure/functions in mammalian cellular systems.

Abstract

The work delineated in this research thesis aims to achieve advances in understanding nuclear structure-function interrelationships. Two natural physiological processes---heat-shock and differentiation---have been used in order to provide a clearer understanding of the "big picture" that links structure and functions together. I have performed experiments using mild or severe heat-shock on HeLa S3 cells and I differentiated L6E9 myoblasts into skeletal muscle fibers. Microscopic and biochemical analysis were used in order to assess the effects of heat-shock and differentiation on nuclear morphology. A series of antibodies specific to the nuclear periphery such as: lam in-associated-polypeptides, emerin, lamins A/C and lamin B were used to analyze structural changes that occurs at the nuclear periphery. Similarly, nuclear matrix antigens such as the proliferating cell nuclear antigen or PCNA, the nucleocytoplasmic shuttling protein 2A7, 2H12 and fibrillarin, two nucleolar proteins, were used as tools to assess structural changes that occur in the nuclear morphology. (Abstract shortened by UMI.)