lo2 How do chromatin remodelers shape chromatin?

What class of proteins controls the spatial positioning of nucleosomes?

Chromatin 'remodelers'.

How do chromatin remodelers function to move or change nucleosomes?

They use ATPase domains to shuffle, evict, or remodel nucleosomes.

What are the different outcomes of ATP-dependent chromatin remodeling?

Remodeling can drive nucleosome sliding, make nucleosomal DNA more accessible, disrupt the octamer structure (often by evicting H2A/H2B dimers), mediate the exchange between histone variants, or result in the complete eviction of the histone octamer.

What are the four major Snf2 ATPase subfamilies of chromatin remodelers?

SWI/SNF, CHD, ISWI, and INOSO.

What is the function of ISWI-containing complexes?

They are responsible for sliding nucleosomes to arrange their regular spacing along chromatin.

What is the function of the SWI/SNF (BAF) complex?

It controls accessibility and is involved in gene activation.

How did scientists demonstrate that the SWI/SNF complex can shuffle nucleosomes?

A 1999 study used a 'sliding' assay, which showed that in the presence of ATP, SWI/SNF could shuffle nucleosomes along a DNA template.

What is the structure of the BAF complex in relation to the nucleosome?

The huge (>2MDA) BAF complex wraps entirely around the nucleosome to facilitate its sliding/remodeling activi