Question

Actin Microtubules Intermediate Filaments Intracellular Preference Location Treadmilling in in Test ube Treadmilling in living cell Any unique characteristics

Answer 1

	Intracellular location	Treadmilling in test tubes	Treadmilling in living cell	Unique characterstics
Actin	Mostly present in cytoplasm and cell nucleus, these are attached to the plasma membrane barbed end and pointed towards the interior Mostly seen in all muscles,which provides support, cell motility	By polymerising the monomeric acrin into a gelsolin actin complex, in the presence of KCl and MgCl2 at 37Degress the rate constant of dissociation of subunits determines the about 2 micron/hr	Subunits of the actin molecules binds to the plus end of the tubulin protein which grows into chain of tubulin molecules which needs nucelotide Triphosphate	Muscle contraction it plays a vital role. Directional sliding behaviour is unique feature of actin filaments
Microtubules	These are component of the cytoskeleton, present all the cytoplasm These are very important for cellular process maintaininf of the cell together Cilia,flagella,spindle fibres are made up of microtubules they provide platform for intracellular cellular transport,movement of secretory vesicles,organelles,intra molecular assemblies.	By using confocal microscope the flourescent speckled microtubules were bound to the covered glass surface by the use of kinesin motors and plus end rapidly grows.	In living cells these are anchored by the centrosomes at minus ends these occurs depolymerisation adn repolymerisation at the plus ends,	Spindle apapratus are very essential for cell division which are made up of micro tubulins
Intermediate filaments	nucelar lamins are made of intermdediate filaments. these are principle components of the cytoskeleton They provide mechanical strength to the cell and tissues keratins are examples of the intermediate filaments these are expressed majorily in epithelial cells,horns,hairs,nails	in invitro they lack polarity irrespective of actin and microtubules treadmilling is rather different they do not undergo treadmilling like other cytoskeleton organelles	Intermediatory filaments forms stable filamentous structures which incorporates continously to grow as non polar fashion	they are mostly involves in neuronal synapses called neurofilaments which upon radial growth of axons and determine axon diameter.