function of LiCl in ChIP wash buffer - (Apr/19/2006 )

What is the purpose of the LiCl buffer during the wash steps in ChIP assay? As far as I know LiCl precipitates RNA - so how would it help in ChIP if RNA is precipitated and not soluble to be washed away? java script:emoticon(':unsure:',%20'smid_13')

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I was wondering about this too..According to the FAQ on the upstate website -

5. What is the purpose/chemistry behind the use of LiCl and NaCl in the wash buffers. Why do we alternate between these? The use of different types of salts improves the effective removal of non-specific chromatin interactions with the agarose beads. Lithium is also soluble in buffers containing high amounts of SDS.

(Although buffer III doesn't contain SDS!)

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