bio361week9

Week 9

Major concept goals

-At equilibrium actin microfilaments have equal rates of assembly and disassembly from each end leading to tread milling behavior

-The 4 steps of cell crawling

-How actin polymerization is the "motor" that leads to membrane protrusion during cell crawling

-The stages of the nuclear cycle

-MPF is sufficient for promoting M-phase

Overview of content

I. Cell crawling   

    A. Actin assembly into microfilaments

        1. Nucleation by Arp2/3

        2. Treadmilling of microfilaments at equilibrium

    B. The 4 steps of cell crawling

    C. Extending the cell membrane forward

        1. Lamellipodium

        2. Structure and function of actin in the lamellipodium

    D. Extracellular matrix adhesion during cell crawling

II. Analyses of myc(-) mouse phenotypes

    A. Cell size and cell number determine organism size

    B. What controls cell number in an organism?

        1. Rate of cell division

        2. Rate of cell death

III. Cell division

    A. What happens during cell division

    B. What needs to happen for a successful cell division

       1. Duplication

       2. Segregation

    C. The nuclear cycle (often called the cell cycle)

        1. DNA content during the nuclear cycle

IV. Regulation of the nuclear cycle    

    A. What needs to be regulated?

    B. Identification of MPF using cell-cell fusion experiments

    C. How to find MPF?