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RNR polimerazės III promotoriai

Jungiasi TFIIIA

Jungiasi TFIIIC

Jungiasi TFIIIC

Jungiasi TFIIIC

TFIIIA ir TFIIIC padeda prisjungti TFIIIB transkripcijos faktoriui

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RNR polimerazės II promotoriai

Šis promotorius dažniausiai naudojamas embrioninio

vystymosi metu

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Kompleksą gali sudaryti virš 85

polipeptidų

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• 1. Covalent modification of histones– Amino terminals of histones are modified in various ways

• Acetylation; phosphorylation; methylation

Adds acetyl groups, thereby loosening the interaction

between histones and DNA

Removes acetyl groups, thereby restoring a tighter interaction

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• 2. ATP-dependent chromatin remodeling– The energy of ATP is used to alter the structure of

nucleosomes and thus make the DNA more accessible

Proteins are members of the SWI/SNF family

Acronyms refer to the effects on yeast when these enzyme are

defectiveMutants in SWI are defective in

mating type switching

Mutants in SNF are sucrose non-fermenters

These effects may significantly alter gene expression

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Skirtingų organizmų SWI/SNF kompleksai

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Chromatino surinkimo ir transkripcinės aktyvacijos, dalyvaujant SWI–SNF, modelis