To Investigate the Biochemical Properties of Various Isoforms of Tropomyosin Expressed in E-coli

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Acknowledgement

I would take this opportunity to thank my research supervisor, family and friends for their support and guidance without which this research would not have been possible.

DECLARATION

I, (Your name), would like to declare that all contents included in this thesis/dissertation stand for my individual work without any aid, & this thesis/dissertation has not been submitted for any examination at academic as well as professional level previously. It is also representing my very own views & not essentially which are associated with university.

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ABSTRACT

Actin filaments play an important role in a number of biological cal functions such as muscle contraction, cytoskeleton organization summer, transport of organelles. Network of short actin filaments supports the cell membranes, sewn in bundles of filaments are sound receptors in the stereocilia. Actin filaments are polar, blunt (fast growing) and acute (Slow growing) ends are different both in structure and in dynamic properties. In the muscles rapidly growing ends of assets new filaments are turned to Zlinii. NATs have been the most extensively studied in yeast. Here, three NAT complexes, Nata / B / C, have been found for most N-terminal acetylation of alpha. Have sequence specificity of their substrates, and are believed to be associated with the ribosome, which acetylate nascent polypeptide chain. Some proteins form supramolecular complexes, whose stability is governed by the same principles that govern the stability of secondary structures, tertiary and quaternary. For example, in muscle there is a supra-molecular complex of multiple copies of a limited number of proteins. Actin is a polymer that is formed by the association of globular protein monomers (G actin) in a helical structure (F-actin) to form thin filaments. F actin is a fibrous protein consisting of two rows of helically coiled monomers and has no catalytic activity.

TABLE OF CONTENTS

ACKNOWLEDGEMENTII

DECLARATIONIII

ABSTRACTIV

CHAPTER 1: INTRODUCTION1

CHAPTER 2: MATERIAL AND METHODOLOGY9

Protein expression and purification9

Initial characterization10

Results12

CHAPTER 3: DISCUSSION14

CHAPTER 4: CONCLUSION16

REFERENCES19

CHAPTER 3: DISCUSSION

The length of the actin filaments is constant in the striated muscle sarcomere, the framework that underlies the membrane of red blood cells in the stereocilia the inner ear and the microvilli of intestinal epithelial cells. Tropomyosin is a long protein that associates with actin, a highly conserved thin filament protein found in organisms from yeast to humans. Actin, a major part of the cell's cytoskeleton, drives shape changes and cellular locomotion in many types of cells, and is part of the contractile apparatus in muscle cells. (Mak 2007, 208) Tropomyosin binds to actin ad acts as a molecular barrier, essentially covering up active sites that are required for actin to interact with other proteins. In turn cellular signals can trigger additional regulatory proteins to move tropomyosin, dislodging the barrier in order to allow actin to associate with remodeling and motor proteins. (Martins 2008, 84)

"Previous studies examining tropomyosin in isolation suggested that it is a coiled coil that matches the shape of actin filaments and is arranged along their surface. However, a complete elucidation of tropomyosin-based regulatory mechanisms requires ...