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Flashcards in Mitosis Deck (77):
0

cell cycle phase: cells grow in size

G1

1

cell cycle phase: DNA replication

S phase

2

cell cycle phase: cell prepares for mitosis

G2

3

cell cycle phase: mitosis

M phase

4

7 phases of mitosis from first to last

interphase, prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis

5

number of times centrosomes duplicate during cell cycle

once

6

this increases dramatically when two centrosomes move apart

gamma - TURC

7

an increase in gamma-TURC when centrosomes move apart causes:

centrosome maturation

8

these link sister chromatids

cohesins

9

At the end of S phase, pair of identical sister chromatids are glued together along entire length by:

cohesion complex

10

coiled coil cohesion subunits with ATPase domain at one end

Smc1 and Smc3

11

cohesin subunits connect ATPase head domains that form circle enclosing sister chromatids

Scc1 and Scc3

12

cohesion complex disrupted at this part of mitosis phase

metaphase-anaphase transition

13

protein complex laid down in S-phase to keep sister chromatids together

Cohesins

14

MT based machine dedicated to separating the sister chromatids

mitotic spindle

15

3 classes of mitotic spindle MTs

astral, kinetochore, polar

16

mitotic spindle class extends from the spindle pole to cell cortex

astral

17

mitotic spindle class exdends from spindle pole to chromosome

kinetochore

18

mitotic spindle class extends from one pole toward metaphase plate and interacts with MTs from other pole in anti-parallel fashion

polar

19

mitotic spindle class responsible for pushing duplicated centrosomes during prophase (maintaining spindle structure) and pushing spindle poles apart in Anaphase B

polar

20

necessary components for mitosis

tubulin, ATP, cytoplasmic proteins (from egg), centrosomes, DNA, nuclear proteins (from sperm)

21

phase with low numbers of catastrophies

interphase

22

phase with high numbers of catasrophies

mitosis

23

these factors regulate stability of mitotic MTs

Kinesin-13 and MAP

24

activity of this protein is stable during mitosis

Kinesin-13

25

activity of this protein decreases during mitosis

XMAP215

26

catasrophy factor during mitosis

Kinesin-13

27

specialized protein complex associated with the centromere

kinetochore

28

kinetochore proteins act to capture:

ends of spindle MTs

29

orientation kinetochores constructed to prevent same pole attaching

back-to-back

30

two layers of kinetochore

outer kinetochore and inner kinethochore

A image thumb
31

binds to DNA and activates Ran in the nucleus

Ran-GEF

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32

cycles in and out of nucleus as part of nuclear-import-export machinery

Ran

33

Ran type distributed evenly throughout cytoplasm

Ran-GAP

34

concentration of Ran-GTP near chromosome

high Ran-GTP concentration

35

Ran-GTP activates proteins that induce release of:

MT stabilizing factors

36

MT attachment at chromosomes remains weak until:

bi-orientation occurs

37

Bi-orientation of MT attachment to kinetochore creates:

tension

38

kinetochores assemble at chromosome region marked by:

H3 Histone variant, CENP-A

39

long and flexible complex links + end of MT to Inner kinetochore

Ndc-80

40

Ndc function controlled by proteins in:

Chromosomal Passenger Complex (CPC)

41

location of CPC during early mitosis

inner centromeric region of chromosomes

42

CPC contains this kinase

Aurora-B

43

kinetochore component in centromeric region phosphorylated by Aurora-B

Ndc-80

44

component of kinetochore has weak association to MT

Ndc-80

45

outer kinetochore part continuously removes phosphates from Ndc-80

PP1 (protein phosphatase 1)

46

bi-orientation pulls both kinetochore away from:

CPC

47

unphosphorylated Ndc-80 has strong attachment to:

+ end of MT

48

chromosome arm moves away from pole due to protein

Kinesin-4

49

during mitosis kinesin-4 interacts with this MT type

astral MT

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50

orientation that first kinetochore binds to astral microtubule

laterally

51

if first attachment laterall to kinetichore, chromosome slides toward spindle pole using this motor protein

dynamin

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52

name for when chromosomes at midpoint b/w two poles

chromosome congression

53

provides strongest force pulling chromosomes toward pole

Dynein/dynactin

54

Kinesin-13 facilitates force pulling chromosomes toward pole by:

depolymerizing + end of microtubule

55

protein located on chromosome arms with head oriented away from chromosome binds

Kinesin-4

56

Kinesin-4 on chromosome arms binds this and pulls arms toward center of spindle

polar MTs

57

after congression this complex released from kinetochore and moves to pole

dynein/dynactin

58

FL kinetochore MT dimers treadmill by moving toward this end

- end

59

anaphase beins when cohesins rings around sister chromatids are removed by:

separase

60

phase where separation of chromatids occurs without separation of spindle poles

Anaphase A

61

during Anaphase A Kinesin-13 depolymerizes:

both + and - MT ends

62

this remains at midzone as chromosomes pulled apart during anaphase

CPC

63

this associates with polar MTs during anaphase

CPC

64

this complex joins CPC and contains a + end directed kinesin motor protein

centralspindlin

65

recruited by centralspindin during anaphase B

Cyk4

66

Cyk4 is an exchange factor for:

RhoA

67

RhoA-GTP activates:

formin

68

nucleates assembly of actin filaments in contractile ring

formin

69

Anaphase B: polar MTs slide in opposite directions catalyzed by:

Kinesin-5

70

Anaphase B: this anchored to plasma membrane and walks to - end of aster MTs, pulling spindles to cortex

Dynein/dynactin

71

cleavage furrow model: astral MTs carry factor to future site that promotes actin-myosin contractility

Astral Stimulation Model

72

cleavage furrow model: polar MTs generate signal that induces cleavage planes

central spindle stimulation model

73

cleavage furrow model: astral MTs carry factor that inhibits actin-myosin contractility at cortex and furrow forms at site of least inhibition

astral relaxation model

74

cleavage furrow model: evidence shows that cleavage can form between centrosomes not linked by mitotic spindles

astral stimulation model

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75

cleavage furrow model: evidence shows that blocking astral MTs results in actin-myosin contractility throughout cell cortex

astral relaxation model

76

cleavage furrow model: rhoA forms ring in cell cortex and cyk4 is localized to equatorial plane of cell

central spindle stimulation model