Term paper - getting started and finishing it: hints - tubulin folding pathway: complexity at its best 6-1 Term paper/ tubulin/ etc.: Lecture 6

Patiently wait until the end of next week You will have a better idea as to what you find interesting Pick out a topic that is broad (biogenesis, degradation or related topic) then narrow down a subject by reading a review or two (I will suggest some reviews) Narrow down subject even further, e.g., to a protein or a process Search and read the latest literature on that topic Think of interesting questions that need to be addressed Write 5-page Term paper according to guidelines 6-2 Term paper

6-3 Tubulin assembly α tubulinβ tubulin αβ-heterodimer assembled microtubule

6-4 - archaeal FtsZ is the homologue of eukaryotic tubulin - first tubulin to be crystallized; shows the power of crystallizing proteins from different sources - structure of alpha-beta-tubulin heterodimer is now also known (TREMENDOUSLY difficult to obtain; used electron diffraction) Lowe and Amos (1998) Crystal structure of the bacterial cell-division protein FtsZ. Nature 391, same group also published structure of MreB, a bacterial protein that forms filaments and has a structure that resembles actin van den Ent et al. (2001) Prokaryotic origin of the actin cytoskeleton. Nature 413, FtsZ crystal structure

6-5 Tubulin folding pathway Tian et al. (1997) J. Cell Biol. 138,

- Rbl2p is the yeast homologue of cofactor A - binds monomeric  -tubulin - suppresses deleterious effects of excess  -tubulin in vivo - competes with  -tubulin in the  - tubulin heterodimer (therefore binds near native state?) - surface mostly hydrophilic; dimer interface has hydrophobic residues - may act as a dimer Crystal structure of Rbl2p, the cofactor A for  -tubulin folding 6-6