What Is the Difference Between the Trithorax (TrxG) and Polycomb

question 17

Multiple Choice

What is the difference between the trithorax (TrxG) and polycomb (PcG) complexes of proteins?

• A) TrxG proteins methylate lysine 27 on histone H3 while PcG complexes methylate lysine 4 on H3
• B) Methylation of lysine at position 4 on H3 results in silencing of gene expression
• C) TrxG complex proteins activate gene expression by methylating lysine 4 on H3, while PcG complex proteins repress gene expression by methylating lysine 27 on H3.
• D) Methylation of H3 on lysine 27 can result in activation of transcription

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Definitions:

Basal Cell Carcinoma

A type of skin cancer that begins in the basal cells and is often caused by exposure to ultraviolet (UV) light.

Squamous Cell Carcinoma

a type of cancer that begins in the squamous cells, which are flat cells found in the skin and other organs.

Eczema

A medical condition characterized by patches of skin that become inflamed, itchy, red, cracked, and rough.

Scabies

A contagious skin infestation caused by a tiny mite Sarcoptes scabiei, characterized by intense itching and a pimple-like rash.