- , . : , (, ) , : .
~2:1; , ( , S) , , : [ ]S., , 16 16S .
, , : , , ~3106 70S, 70S 50S 30S:
70S 50S + 30S
, ~1/2 2/3 , , 70S 50S 23S ( ~3000 ) 30S 16S ( ~1500 ); (5S 50S 5S 5.8S ).
(, , )
( . translatio ) () (, ), .
. . , 2 : . () , , , . , , .
, (). , , (), , , , . - --, -. , , --, (, GGU , CCA, ).
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, , , , .
.
.
(-) .
, ( , ), . , , . AUG- .
AUG-, . . -. ( ). 5'- 5'-. , AUG , AUG-.
(. initiation factors, IF; eIF, . eukaryotes).
- : AUG , .
(30S) , , IF1, IF3, , , IF2. :
IF3, 30S-, (50S) , . , IF2.
IF2 , .
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IF1 , -, ( ) IF2 IF3
30S , (. RBS, ribosome-binding site). , -, AUG, , -, 16S . , AUG , . , 30S- - IF2, . 50S-, . .
AUG: - () - ( ).
(, ) 5'- , , AUG. 5'- , 7-, 5'- .
, IRES- , , IRES (. Internal Ribosomal Entry Site, ) , , AUG. IRES- , .
, ()- (, ) . e IF3 eIF4F, 5'- , .. - " ". , .
, , 3' 5' . .. , - - .
-
, , , 5'- [m7G(5')ppp(5')N] 3' ()-, , , 13 (eIF), 31 . , , - . :
;
- (Met-tRNAiMet);
5'-, (), ;
-;
-