1. Lesson 1: Foundations to Set the Stage:
2. Focusing on Cellular Structure and Function:
3. The Normal Cell Cycle: -The cell cycle refers to the ordered seres of
processes of DNA replication and mitosis, or cell division
-Cell nucleus regulates these processes by gathering and processing complexes
molecular information
4. Interphase and Mitotic Phase: Cell division produces two identical cells
through these two major phases
5. During interphase:: Cell grows and DNA is replicated through the following
three steps:
1: First growth phase (G1 or first gap)
2: Synthesis phase (S phase)
3:Mitotic Phse (M phase)
6. First Growth Phase (G1 or first gap): -cells increase in size
-reproduce RNA
-"quality assurance" test that the cell will be ready to synthesis DNA
-Length of time is variable, can be from hours to days
7. Synthesis Phase (S phase): -DNA replicates
-Results in the formation of identical pairs of DNA (chromatids)
-which are attached a t the centromere
-lasts 2-10 hours
8. Mitotic Phase (M phase): -Replicated chromosomes are aligned, separated,
and move into 2 new, identical daughter cells
-takes about 30-60 minutes
, ONS/ONCC Chemotherapy Immunotherapy Certificate
9. Major points of cell regulation are entry and exit from: -G1 checkpoint -S
Phase
-G2 checkpoint
-M phase
10. Restriction Point: -The transition from the resting phase into an actively
dividing phase (G0-G1) is a point where cellular transformation can occur
-During this time, cells pass through a transition phase known as a restriction point
-Extracellular growth factors trigger reentry into G1, and GF are required to send
the cells past the restriction point, or the point of no return
11. G0 Phase (resting phase): -After mitosis, cells may enter back into the G1
phase or go into a resting phase, known as G0
-Most cells in the human body reside in G0
12. -Exceptions to this are those that are (Resting in G0 phase): -Exceptions
to this are those that are metabollically active, such as
-granulocytes
-and the epithelium of the GI tract
13. Cell Cycling Time: Amount of time from mitosis to mitosis 14. Cell cycle
video and image:
http://highered.mheducation.com/sites/0072495855/student_view0/chapter2/anim
ation__how_the_cell_cycle_works.html
15. Check points in the Cell Cycle: Keeping it All Under Control: -The cell
cycle is carefully controlled through a series of checkpoints
-Variation in duplication or distribution of chromosomes during cell division can alter
the genetic information passed on to daughter cells, leading to cellular dysfunction
and disease, such as cancer
-These checkpoints monitor for DNA integrity and control progression through
mitosis
, ONS/ONCC Chemotherapy Immunotherapy Certificate
16. Progression through the cell cycle is controlled through two proteins::
1. cyclines (D, E, A, B)
2. Cyclin-dependent kinases (CDKs)
-Cyclin-CDK complex allows the cell to progress through each phase of the cell
cycle
17. Locations of proteins Cyclins (D, E, A, B) and CDKs: -(G0-G1) : Cyclin D
and CDK 4/6
-Early S: Cyclin E and CDK 1/2
-Late S: Cyclin A and CDK 1/2
-G2: CDK 1/2 and cyclin A
-Before M: CDK 1 and Cyclin B
18. Inhibitory proteins: -prevent progression of the cycle when DNA damage is
detected
-An example of an inhibitory protein is p53 (AKA TP53)
19. DNA Damage Checkpoints: -If DNA damage is present, cells are
programmed to stop dividing or undergo apoptosis (programmed cell death)
-The retinoblastoma protein (Rb), p53, and p21 are some of the most well-
understood inhibitory proteins (IP)
20. Inhibitory proteins p53: -Levels of this IP regulate several important target
genes
-Will increase when DNA damage is present
-Protects against inappropriate signal proliferation
-sometimes called the "suicide gene"