BIO230H1 Lecture Notes - Lecture 2: Nocodazole, Tubulin, Dynamin
BIO230
Lecture 2
!
! "#$%&'()(*+,-!"#$%$&$'"(')*'protofilaments;!!
----------------------------+',-$'."/-0%123'43%((202#&5'2#3$'.-/!0!+12'-#3'/30!+12!
'
! 4!5()(*#1--#3-6!5()(*#1-6'7"#"720%!'.0"&2%#$'&,-&'7-82'-',2&20"3%7209':-!,'
.0"&"(%/-72#&'!"#$%$&$'"('&,2$2',2&20"3%720$9';('<"='/""8'-&'&,2'.0"&"(%/-72#&'(0"7'
&,2'&".'&"'&,2'>"&&"7?'-/.,-+'-#3'>2&-+&=>=/%#'-02'-/&20#-&%#@9''
'
! 7!5()(*#1-.--'.0"&2%#'A,%!,'>%#3$'&"'-/.,-+'-#3'>2&-+&=>=/%#',2&20"3%720$'-&'&,2'4+
5'2#3'"('-'7%!0"&=>=/2'><'("07%#@'-'0%#@B'%&'#=!/2-&2$'&,2'7%!0"&=>=/2'-#3',2/.$')*'
.0"&"(%/-72#&$'&"'-$$27>/2'%#&"'-'&=>2?'A,%!,'A%//'>2'@0"A%#@'-A-<'(0"7'&,2'
#=!/2-&%"#'$%&2'44C5+2#359'
'
! 8+1'%&9&:+-.'-#'"0@-#2//2'&,-&'$20D2$'-$'&,2'7-%#':#$%&'()(*+-&%;<1#=#1;-
$+1'%+'/"5>80'"('&,2'-#%7-/'!2//B'-/$"'$20D2$'-$'-'02@=/-&"0'"('!2//'!<!/29''
''''''''''''''''E2#&0"$"72'!"#$%$&$'"('F'$+1'%#&*+9'$=00"=#323'><'.0"&2%#$'A%&,'γ-Tubulin-
#=!/2-&%"#'$%&2$9'G2!-=$2'H+I=>=/%#'%#'&,2'7%!0"(%/-72#&$'%$'/"!-&23'-&'&,2'4+5'2#3?'
!2#&0"$"72'A%//'-$$27>/2'4+5'2#3$'"('7%!0"(%/-72#&$?'A,%/2'4C5+2#3$'A%//'>2'$&%!8%#@'"=&'
'
! ?@1<:#$-#19'<)#*#'@-.-@0"A%#@'J'$,0%#8%#@'"('7%!0"&=>=/2$'-#3'&,2#'02&=0#%#@'&"'
%&$'"0%@%#-/'$&-&29'K//"A$'7%!0"&=>=/2$'&"'$2-0!,'&,2'(=//'*L'$.-!2'"('&,2'!<&"./-$79''
'
!-8<A-&B-C5D!-)&(12-'()(*#1-.!tubulin!subunits!with!GTP!at!the!(+)$end!of!growing!
microtubules!which!will!later!be!hydrolysed!to!GDP-bound$tubulin$as!the!more!GTP-tubulin!
subunits!are!added.$$
The!cap!should!be!located!at!the!(+)!end!and!protect!the!microtubule!from!disassembly!
(catastrophe).!!
)
"&'&%-A%&'+#19-.'.0"&2%#$'&,-&'&0-#$."0&'-'!-0@"'42MN'D2$%!/25'-/"#@'&,2'7%!0"&=>=/2'
4OA-/8<O'@=<$5''
''''''''?@1+#1-7"D2$'&"'7%!0"&=>=/2'4+5+2#3B'''4&,%$'%$'PQI'dynamin)(0"7'R2!&=02')5''
''''''''E#1+9#1-7"D2$'&"'7%!0"&=>=/2'4C5'2#3B'
F2<A'&%-A%&'+#19-6'.0"&2%#$'&,-&'/%#8'&,2'!-0@"'&"'&,2'7"&"0'.0"&2%#$'4S=$&'-!&'-$'-'
!"##2!&"059''
'
G&$&2<=&*+-6'-#'-@2#&'A,%!,'2M20&$'%&$'2((2!&'%#'!2//$'><'%#&20(20%#@'A%&,'&,2'
."/<720%1-&%"#'"('7%!0"&=>=/2$'4:#$%&'()(*+-#1H#)#'&%59'
'
"+*<1&9&:+-'+'-'D2$%!/2'A,%!,'!"#&-%#$'melanin'4'-'.%@72#&'02$."#$%>/2'("0'3-08'!"/"=059'
42MN'I,2'K(0%!-#'!%!,/%3'(%$,5''
'
'
42
BIO230H1 Full Course Notes
Verified Note
42 documents
Document Summary
Has polarized (different) ends (-)-end and (+)-end. -tubulin and -tubulin monomeric proteins that make a heterodimer. If you look at the protofilament from the top to the bottom, alpha- and beta-tubulin are alternating. -tubulin a protein which binds to alpha- and beta-tubulin heterodimers at the (- ) end of a microtubule by forming a ring; it nucleates the microtubule and helps 13 protofilaments to assemble into a tube, which will be growing away from the nucleation site ((+)-end). Centrosome an organelle that serves as the main microtubule organizing centre (mtoc) of the animal cell; also serves as a regulator of cell cycle. Centrosome consists of 2 centrioles surrounded by proteins with -tubulin nucleation sites. Because -tubulin in the microfilaments is located at the (-) end, centrosome will assemble (-) ends of microfilaments, while (+)-ends will be sticking out. Dynamic instability growing / shrinking of microtubules and then returning to its original state.
