The Replication Problem (telomere problem)

[Transformers]

I was wondering...does the replication problem (in replicating DNA at the ends) apply to only the daughter strand of the lagging strand or BOTH the leading strand and lagging strand. My Mcat book focuses only on the lagging strand and I would guess it applies to both in the sense that at the 3' ends of the template (lagging and leading) strands, you'll always that primer, that if removed, would produce an abridged strand.

To draw it out:
Leading: 3'-----------------------5'
Daughter: 5'primer----------------->3'

Lagging: 5'-------------------3'
Daughter: 3'<---<----<--primer5' (okazaki)

I understand the telomerase mechanism but I want to be sure that both the 5'-->3' and 3'--->5' template strands (leading and lagging) will have this problem BECAUSE at the VERY ends (at the 3' of the templates), the daughter strand will have still have that primer.

Thanks

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[RogueUnicorn]

only the lagging strand, but remember that both daughter strands is the lagging strand in one side of the replication bubble.

 

[Transformers]

yeah, but think of it this way....so each replication bubble should have 2 replication forks...however at the ENDs of the DNA, you can only have 1 fork at each end...shouldn't that evidently lead to those problematic primers being formed complementary tot he 3' ends of both the parental strands? Thus the replication problem exists for both strands...that is to say if given a double stranded piece of dna that is being replicated, both daughter strands willl be shorter than the parental DNA and its not just one daughter strand that is normal and the other that isnt.

 

[RogueUnicorn]

yeah, but think of it this way....so each replication bubble should have 2 replication forks...however at the ENDs of the DNA, you can only have 1 fork at each end...shouldn't that evidently lead to those problematic primers being formed complementary tot he 3' ends of both the parental strands? Thus the replication problem exists for both strands...that is to say if given a double stranded piece of dna that is being replicated, both daughter strands willl be shorter than the parental DNA and its not just one daughter strand that is normal and the other that isnt.

yes you have that correct.