Some aspects of biochemistry of fibrous proteins in brain

Abstract

Recent investigations in a variety of laboratories have shown that the fibrous proteins actin and tubulin are involved in a wide spectrum of cellular activities, including motility and the transfer of materials across cell membranes. The investigation that forms the subject of this thesis used the wealth of background information on events following section of the XIIth cranial (hypoglossal) nerve in the rat, to see what part actin and tubulin play in the withdrawal and re-establishment of synaptic boutons: to investigate synapse modelling. Quantitative protein changes were measured by polyacrylamide gel electrophoresis. Cellular location of the changes was shown by immunofluorescence microscopy. This work was extended to include an investigation of a small amount of human material. Using the same analytical techniques as were employed in the experimental work on rats, a tentative identification is made of the material that forms the neurofibrillary tangles in presenile and senile dementia. Suggestions are made about the nature and origin of these diseases. Some observations are also made about the protein skeletin, but because isolation and characterization methods currently available give conflicting results about the true nature of this important cellular component, it was excluded from an in depth study pending more detailed information about it.