Methyle missmatch repaire:

 Methyle missmatch repaire:


Methyle missmatch repaire Is specially designed to excised abnormal bases from DNA strand.If urasil incorporated in DNA due to the deamination of cytosine, it will bind with adenine.Where instead of G-C base pair A-U base pairing occurs. Now the unwanted basr has to be remove this unwanted base has to be remove from DNA. The cell repairing mechinary will removed this unwanted base so that the replication process will worked smoothly. For methyle miss match repaire mature gene conducts protaine will worked. Mute gene syntheses mute S,mute L and mute H.



After replication there is one daughter strand &parent strand& one parent strand. In the parent DNA strand there is a methyle grup in a specific site ie. GATE.The methyle grup attach to adenine by DAM enzyme (deoxyadenine methylase). Marking of adenine in methyle grup is helpfull to recognised the parent of DNA by cell.


Step 1. The mute s recognised the site with urasil but it canot recognised which one is the parent DNA strand & which one is the daughter strand.


Step2. Mute L come & recognised the parent strand & bind with the sequence with methyle grup.


step3. Mute L formes a loop like structure to brings all the regions closer so that it would be easier to cut off that region.


step4. Mute h will be recruit at the loop structure & a cleaves urasil from the DNA.



step5. after cleaving it and gap generated. Then helicase in corporated in DNA spread & seperate the DNA strand & taking the portion away creatine.This gap is field by DNA polymerase 1 & the nicks is shield by DNA ligase.


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