Why does 28S rRNA appear at around 4000 nt on the bioanalyzer graphic even if the 28S/18S ratio is 2,7? The size of 28S is supposed to be 5034 nt. The gel itself is not denaturing but doesn’t the 28S denature if you heat it shortly before running the analysis? Or does it de-denature quickly afterwards? (It’s rRNA from HeLa cells, and I found an example on the internet showing Raji cells with a 28S/18S ratio of 2,7 and a 28S band size of 3900/4000 nt, so I figured the 28S rRNA would still be intact.)
I can’t find any explanation for this on the internet, so I hope someone here can help me out with this one.
Thanks a lot in advance.