How do Molecules form Living, Moving, Reproducing Cells?

1683, Leeuwenhoek: “An unbelievably great company of living animalcules, a-swimming more nimbly than any I had ever seen up to this time. The biggest sort bent their body into curves in going forwards."

1988, Francis Crick: “Every living cell and every biological macromolecule is the end result of natural selection, which had acted over billions of generations to produce complexity from ordinary physics and chemistry”

Molecular Hierarchy of the Cell

DNA Proteins(Enzymes and Motors)

Protein Assemblies (Cytoskeletal Filaments)

→ →

Moving Parts: Motor Proteins on Polymer Tracks

The CiliumThe Mitotic Spindle

Cellular Machines based on MTs and motors

“The Cell as a Collection of Protein Machines: Preparing the Next Generation of Molecular Biologists”.

(Alberts, B (1998) Cell 92: 291).

Protein Machine MotorReplication Machinery Helicase

Transcription Machinery RNA polymerase

Mitochondrial ATP synthase F1F0 ATPase

Bacterial Flagellum Flagellar rotary motor

Muscle Sarcomere Myosin-2

Lamellipodium Dendritic Actin Network

Cilium MT motors

Mitotic Spindle MTs and mitotic motors

Assembly and Function? Biochemistry, Genetics, Microscopy, Quantitative Modeling.

Bacterial (prokaryotic) Cells.

Locomoting Eukaryotic Cells.

Mechanism of Eukaryotic Cell Locomotion.

Scanning E.M. of the leading edge.

E.M. of Actin Filaments in the Leading Edge.

Ribbon Diagram of Atomic Structure of Actin.

Structure of Actin Filaments – helical symmetry.

Actin Filament Assembly and Force Production.

Actin filament polymerization drives Listeria Motility.

Listeria Motility

Julie TheriotStanford University Medical School

Eukaryotic Cell Reproduction; Mitosis and Cell Division.

Mitosis studied in the Drosophila melanogaster Syncytial Embryo

Sullivan Lab

GFP-tubulin; histone-RFP;480 seconds total time(Ingrid Brust-Mascher)

Mitosis in Drosophila Embryos.

MOTOR PROTEINS AND MICROTUBULE-BASED MACHINES.

Mechanism of Mitosis.

Metaphase

Anaphase A

Anaphase B

Cytokinesis in Animal Cells.