1. Computer Information Processing Input Output Unorganized Data Organized Data Computing www.gls.gov.uk/ Computer Programming

2. Cellular Information Processing Biological scienceprofonline.googlepages.com Input Unorganized Signals Output Cell Function Biological Programming

3. Role of Cell Function in Biology The cell is the fundamental unit of living things Everything that that happens in the organism happens at the level of the cell Biological molecules dictate cell function To understand cells (biological information processing) must understand biological molecules

4. Cell Function Understand Cell Function in Molecular Terms Begin with a question: Are your skin cells different from your heart cells? If so, how? Skin Cells Heart Cells

5. Central Dogma of Biology DNARNAPROTEIN InfoInfo CarrierFunctional Product

6. What kind of cells are these?

7. Making Skin into Heart Alter gene expression of skin cells to make them pluripotent stem cells Pluripotent – capable of becoming different kinds of cells Like embryonic stem cells Grow under conditions that induce differentiation into heart cells (new gene expression) Accomplished by two groups in 2007 One in Japan and one in U.S.

8. Making Stem Cells Expression of four genes change skin cells into pluripotent embryonic stem cells Oct3/4, Sox2, Klf4, Myc Holm Zaehres and Hans R. Schöler, Cell, Vol 131, 834-835, 30 November 2007

9. Once Skin and Now Heart

10. First Observation of Cells Occurred 150 yrs before cell theory (1670) Antonie van Leeuwenhoek (animalcules) Robert Hooke (cells in cork)

11. Remarkable Variety of Cells  200 different types in the human body  All cells can be categorized into 2 basic plans  Prokaryotic (before kernel, before nucleus)  Eukaryotic (true kernel, true nucleus)

12. Eukaryotic Cell (animal)

13. Nucleus Command center for gene expression Contains 95% of the cell’s DNA (genes) Genes are selected for expression Site of RNA synthesis (transcription) Produces mRNA DNA is in a complex called chromatin

14. Nucleus Structure

15. Chromatin DNA-Protein complex (1:1 mass ratio) Proteins are histones (basic amino acids) Histones help to pack DNA (146 bp +linker)

16. ER and Golgi 10.11

17. Cytosol (Cytoplasm) Everything that is not an organelle Much of cellular metabolism occurs in the cytosol Protein synthesis occurs in the cytosol Cytosol is highly compartmentalized Compartments and trafficking is controlled by the cytoskeleton