Buněčný cyklus - principy regulace buněčného růstu a buněčného dělění

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1 Buněčný cyklus - principy regulace buněčného růstu a buněčného dělění

2 Mitóza Dr. B. Duronio, The University of North Carolina at Chapel Hill

3 Buněčný cyklus

4 Kinázy závislé na cyklinech kontrolují buněčný cyklus

5 Kontrola vstupu do mitózy - výsledek využití různých buněčných modelů

6 Dr. B. Duronio, The University of North Carolina at Chapel Hill Experimental Systems Important for Cell Cycle Studies Saccharomyces cerevisiae Arbacia punctulata Schizosaccharomyces pombe Xenopus laevis

7 Cyclin was Discovered in Sea Urchin Embryos can stimulate to lay lots of eggs Protein Level cyclin A cyclin B M M M Time

8 Frog life cycle OOCYTE GROWS WITHOUT DIVIDING (MONTHS) FERTILIZATION FERTILIZED EGG DIVIDES WITHOUT GROWING (HOURS) 1 mm sperm tadpole feeds, grows and becomes an adult fro

9 The Maturation of Frog Eggs An Assay for Maturation Promoting Factor (MPF) Yoshio Masui, 1971

10 MPF Activity Peaks Before Each Cell Division Moreover, MPF has kinase activity

11 Dr. B. Duronio, The University of North Carolina at Chapel Hill

12 r. B. Duronio, The University of North Carolina at Chapel Hill Purification of MPF: The Birth of Cyclin Dependent Kinases This is cdc2 +!! (Cdc28 in S. cerevisiae) This is cyclin!! Which = cdc13 + in S. pombe

13 Fission yeast: Schizosaccharomyces pombe Dr. B. Duronio, The University of North Carolina at Chapel Hill

14 Budding Yeast Saccharomyces cerevisiae Dr. B. Duronio, The University of North Carolina at Chapel Hill

15 Dr. B. Duronio, The University of North Carolina at Chapel Hill Cdc Mutants Arrest at the Same Cell Cycle Phase Permissive (low) temperature Restrictive (high) temperature

16 Cdc Genes Encode Proteins Needed for the G2-M Transition: Studies in S. pombe cdc2 + encodes a kinase Moreover = cdc28 in S. cerevisiae!

17 Phosphorylation of CDK Targets Changes Their Activity Now performs a cell cycle function

18 Jak jsou CDK regulovány? 1. prostřednictvím syntézy a odbourávání cyklinů 2. fosforylací 3. pomocí CDK inhibitory proteins (CKIs)

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20 Cyclin Destruction is Controlled by Ubiquitination Dr. B. Duronio, The University of North Carolina at Chapel Hill

21 Představují cykliny jediný způsob regulace CDK?

22 Exprese cyklinů v jednotlivých fázích BC Dr. B. Duronio, The University of North Carolina at Chapel Hill

23 CDK jsou regulovány fosforylací

24 Conformational Changes Associated with CDK Phosphorylation Free CDK CDK + Cyclin T161 phosphorylation The T-loop blocks Binding of cyclin Phosporylation move

25 Cyclin Dependent Kinase Inhibitors (CKIs)

26 . B. Duronio, The University of North Carolina at Chapel Hill The p21 Family of CDK inhibitors (p21 CIP1/WAF1, p27 KIP1, p57 KIP2 ) active inactive CDK Cyclin + p21 CDK Cyclin p21 p27 Ki p1 Cyclin CDK A 2 Jeffrey et al. (1995) Nature 376:313 CDK 2 Cyclin A Russo et al. (1996) Nature 382:325

27 . B. Duronio, The University of North Carolina at Chapel Hill The INK4 Family of CDK inhibitors (p16 INK4a, p15 INK4b, p18 INK4c, p19 INK4d ) active CDK4/6 Cyclin D + INK4 inactive CDK4/6 + INK4 Cyclin D Russo et al. (1998) Nature 395:237 Brotherton et al. (1998) Nature 395:244

28 Dr. B. Duronio, The University of North Carolina at Chapel Hill CKIs Regulate the G1-S Transition (p16) (p21, p27)

29 Nature Reviews Cancer 2001, 1:222

30 Dr. B. Duronio, The University of North Carolina at Chapel Hill

31 prb Binds to the E2F Transcription Factor Dr. B. Duronio, The University of North Carolina at Chapel Hill

32 G1 Cyclin CDKs Phosphorylate prb Dr. B. Duronio, The University of North Carolina at Chapel Hill

33 Proliferation Signals p16 Regulates RB Phosphorylation

34 Nature Reviews Cancer 2001, 1:222

35 Kontrola buněčného cyklu úzce souvisí s: kontrolou buněčného růstu; přítomností růstových faktorů a dalších růstových stimulů a živin; působením ostatních buněk populace a mezibuněčné hmoty.

36 The Difference Between Growth and Cell Division Cell Division No Growth Cell Division + Growth = Proliferation! Growth with No Cell Division

37 Growth with No Cell Division: A Differentiated Neuron

38 Dr. B. Duronio, The University of North Carolina at Chapel Hill Cell Division with No Growth: Early Development 1 mm sperm

39 Nature Reviews Cancer 2001, 1:222

40 rowth Factors Induce Cell Cycle Progression Dr. B. Duronio, The University of North Carolina at Chapel Hill Growth Factors act at the Restriction Point

41 Nature Reviews Cancer 2001, 1:222

42 . B. Duronio, The University of North Carolina at Chapel Hill Zetterberg and Larsson, PNAS 82:5365 (1985) pm = post mitotic ps = pre-synthetic

43 Growth Factors Induce Gene Expression Dr. B. Duronio, The University of North Carolina at Chapel Hill

44 Growth Factors Induce Cyclin D1 Expression Sherr and McCormick, Cancer Cell, Vol 2, (2002)

45 Dr. B. Duronio, The University of North Carolina at Chapel Hill Mitogen Induced Cell Cycle Progression in Cell Culture

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47 Cell Cycle Checkpoints

48 Cell Cycle Checkpoints Improve Cell Viability Weinert and Hartwell, Science 246:629 (1989

49 How do Cell Cycle Checkpoints Work?

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51 Dr. B. Duronio, The University of North Carolina at Chapel Hill Signal Sensor Transducer Effector

52 Dr. B. Duronio, The University of North Carolina at Chapel Hill

53 Metaphase in a mammalian cell

54 The Metaphase to Anaphase Transition

55 The Spindle Assembly Checkpoint

56 poškození DNA poruchy buň. cyklu poruchy buň. dělení nedostatek živin a růstových faktorů kontaktní inhibice vliv ECM dostatek živin a růstových faktorů mitogeny zástava buň.cyklu (restriction point, checkpoints) setrvání v G 0 fázi apoptóza proliferace

57 eregulace buněčného cyklu a růst nádorových buněčných populací

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