BIOS 222 Lecture 13: BIOS 222 Lecture 13
Document Summary
Cells assemble and disassemble microtubules (mt"s) accord to their needs. Intermediate filaments don"t typically disassemble once they"ve been formed. Relatives in prokaryotes but not the same proteins. Cells make microtic spindle from them and flagella and cilia from them. Can detect mt"s by fluorescent antibodies-using gfp subunits to see where they are in the cell. Staining of mt"s red stain-actin, blue stain-dna, green stain- mt"s. Indication of mt"s s spread in center of cell towards periphery. And if you chill portion of brain to icy temperature, mt"s not visible before undergoing electron microscopy (em). Chill brains to make a homogenate, then begin trying to purify protein that makes up mt"s, lay bile struct up. Hunk of brain with buffer, centrifuge it, can take liquid fraction add mg2, gtp and egta, microtubules reform. Possible to see polypeptide subunits to make up microtub structures. Also, drug based affinity chromatography that produced same result. Structures form spontaneously and reversibly from brain extract.
