...Literally, when I hit the 40% pass mark in my exam on Friday - it's going to be because of you... Though, I won't lie, I'm annoyed that a free video on RU-vid helped me more than the £200 worth of books I bought did.
omg you are amazeballlss! everything makes sense now! I was studying for like 2weeks and nothing made sense, and now one day before.. everything is clear. thank you so much xxx
Thank you, your video is very helpful and easy to understand. Books only help to a certain extent. I could not understand it from a book but just a just simple sentence in this vid explained it all :)
From what I learned from Wikipedia, it seems that histone modifications (such as acetylation as described in this video) are considered as epigenetic mechanisms, although it is not clear if histone modifications are inheritable or not. Histone modifications are considered as epigenetic mechanisms since any modification to the histone in the nucleosome invariably has an effect in gene expression or silencing.
Not quite. Chromatin remodeling generally refers to the idea of taking tightly packed DNA and unpacking it so that transcription can occur (since transcriptional machinery cannot act on condensed DNA). Acetylation is involved in the process of unpacking the DNA. So it is involved in chromatin remodeling. Deacetylation, however, is involved in RE-packing the DNA into chromatin. Does that remodel the chromatin? I suppose so, but I think it is convention to consider chromatin remodeling as unpacking the DNA as opposed to re-packing it. In packed DNA, histones carry a positive charge that allows them to bind fairly tightly to the DNA. Acetylation of the lysine residues on the histones gets rid of that positive charge. Thus, DNA is less attracted to the histones, and the DNA separates from the histones -- it gets unpacked. I hope that helps answer your question(s).
and please can you make a video about phosphorylation and acetylation and whar are the different between them,, I mean the action of phosphorylation should be the oppiste of acetylation? in gene expression
Soulaf Kakel Not a problem. If you have questions on a particular video, ask them in the comments section. If I do not get to it or cannot answer it simply in a comment, I'd suggest emailing me. Phosphorylation and acetylation are both post-translational modifications. I'll be making a video on Post-Translational Modifications for sure.
