1. Molecular motors
At the organism – population level, motors are needed to transfer materials.
At the organelle – organ level, motors are needed to transfer material and information.
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2. Slides borrowed from: http://mc11.mcri.ac.uk/motorhome.html
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3. Motors
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4. Kinesin - Dynein
Kinesin: Most members of the kinesin family of motor proteins walk along microtubules away from the centrosome. Dynein: The dyneins walk along microtubules toward the centrosome).
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5. The Tubulin Autobahn
In the cell itself, microtubules are formed in an area near the nucleus called the "aster". This is also called the Microtubule Organizing Center (MTOC). Microtubules are polar with a plus end (fast growing) and a minus end (slow growing). Usually the minus end is the anchor point in the MTOC. In this figure, the plus end is shown to the left by the numerous tubulin dimers. This is the end that carries the GTP molecules which may be hydrolyzed to GDP.
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6. Actin - Myosin
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7. Perpetual motion - A/GTP
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8. G proteins do it with GTP
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9. Cholesterol transport
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10. Information flows through our body in many different ways.
Information transfer
Information flows through our body in many different ways.
One method is to send out messengers (hormones) that can be recognized by other cells or organs.
GPCRs and nuclear receptors are examples of receptors for this type of information.
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11. First rule of sequence analysis:
If a residue is conserved, it is important.
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12. Second rule of sequence analysis:
If a residue is very conserved, it is very important.
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13. Different levels/types of variability

14. 20 Ei = S pi ln(pi) i=1 Sequence Entropy
Sequence variability is the number of residues that is present in more than 0.5% of all sequences.
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15. Variability is result of evolution.
Entropy - Variability
Variability is result of evolution.
Entropy is the protein’s break on evolutionary speed.
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16. GPCR Location
11 Red
12 Orange
22 Yellow
23 Green
33 Blue
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17. Enzyme active site
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