Mitosis Flashcards
cell cycle phase: DNA replication
S phase
cell cycle phase: cells grow in size
G1
cell cycle phase: cell prepares for mitosis
G2
cell cycle phase: mitosis
M phase
7 phases of mitosis from first to last
interphase, prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis
number of times centrosomes duplicate during cell cycle
once
this increases dramatically when two centrosomes move apart
gamma - TURC
an increase in gamma-TURC when centrosomes move apart causes:
centrosome maturation
these link sister chromatids
cohesins
At the end of S phase, pair of identical sister chromatids are glued together along entire length by:
cohesion complex
coiled coil cohesion subunits with ATPase domain at one end
Smc1 and Smc3
cohesin subunits connect ATPase head domains that form circle enclosing sister chromatids
Scc1 and Scc3
cohesion complex disrupted at this part of mitosis phase
metaphase-anaphase transition
protein complex laid down in S-phase to keep sister chromatids together
Cohesins
MT based machine dedicated to separating the sister chromatids
mitotic spindle
3 classes of mitotic spindle MTs
astral, kinetochore, polar
mitotic spindle class extends from the spindle pole to cell cortex
astral
mitotic spindle class exdends from spindle pole to chromosome
kinetochore
mitotic spindle class extends from one pole toward metaphase plate and interacts with MTs from other pole in anti-parallel fashion
polar
mitotic spindle class responsible for pushing duplicated centrosomes during prophase (maintaining spindle structure) and pushing spindle poles apart in Anaphase B
polar
necessary components for mitosis
tubulin, ATP, cytoplasmic proteins (from egg), centrosomes, DNA, nuclear proteins (from sperm)
phase with low numbers of catastrophies
interphase
phase with high numbers of catasrophies
mitosis
these factors regulate stability of mitotic MTs
Kinesin-13 and MAP
activity of this protein is stable during mitosis
Kinesin-13
activity of this protein decreases during mitosis
XMAP215
catasrophy factor during mitosis
Kinesin-13
specialized protein complex associated with the centromere
kinetochore
kinetochore proteins act to capture:
ends of spindle MTs
orientation kinetochores constructed to prevent same pole attaching
back-to-back