Nucleus Pt. II Flashcards
What’s the difference between an GTP-ase and an Exchange Factor
Ase— suffix means it hydrolyzes and GTP to GDP or ATP to ADP
Exchange Factor — Not a hydrolysis reaction but an exchange — it switches them out.
Quickly draw an image with all the following features:
Cytosol
Nuclear Envelope
Nucleus
Chromatin
Nuclear Pore
Nuclear Lamina

What is Chromatin?
Size and number of folds of DNA?

Definition of Chromatin

What are the histone Proteins?

Features of DNA

Chromatin Fiber
Derived from an extended array of nucleosomes
Chromatin Higher Order Structure

Chromatin



Euchromatin Vs. Heterochromatin

Reading the Histone Code

Epigenetics

Genetics vs. Epigenetics
Genetics — DNA Sequence
Epigenetic’s — Histone Modifications — Actually be inherited — Tells you what histones to acetylate/Methylate and therefore what genes to activate and deactivate.
Function and Overview of the Cell Cycle

Steps in the Mitotic Cell Cycle

Cell Cycle Check Points

Regulation of Cell Cycle Progression

Cyclin/CDK Regulation

G1 - S Transition Regulation
Without RB you lose G1 to S checkpoint so it goes from G1 to S freely and a lot of genetic mistakes/mutations can occur.

Lose RB means you lose the suppression of tumor formation.
If you have a mutation of NES means too much Cyclin D in the nucleus then phosphorylates proteins too early in G1 and sometimes in s-phase and drives the cycle forward prematurely.
CDK/Cyclin regulation of S-Phase

Cyclin/CDK regulation of G2 to M to G1
Mitotic CDK/Cyclin — Cyclin B
Cyclin B levels rise then complexes with CDK
CDK phosphorylates 100’s of proteins.
Lamina Proteins depolymerize

Interphase

Prophase































