Monkeymaniac

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Each of sister chromatids of a chromosme, when they separate during Anaphase, seems to be taking half of the centromere along with it. If this process is repeated, there wouldn't be any centomere left to be divided. So when exactly is this centromere resynthesized to its original size? is it done during G1 or S or G2? Thanks in advance.
 

RogueUnicorn

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the centromere is just chromatin like the rest of the chromosome
 

TFS

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it is just a sequence of DNA (as stated above!)
 

Monkeymaniac

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Ah, yes I see. Since we are on the topic, then is Kinetochore protein synthesizes during G1 phase and splitted evently during anaphase?
 

StIGMA

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The centromere is an incredibly specialized area of chromatin. It has a distinct and unique complement of proteins. Without looking it up, I believe the actual kinetochore (used during M phase) is added during G2 and is not present during G1/S (when the typical centromere proteins are present that simply associate with its unique DNA regions). The kinetochore is present bilaterally on each chromatid and is split evenly.

See this EM: http://www.wadsworth.org/rvbc/kinetochore_1.jpg which in the upper left figure shows the kinetochore being pulled by microtubules. The puffy stuff on each side of the kinetochore is the adjacent condensed chromatin. This is one chromatid, with the other one off the figure.