Cytoskeleton

Created by

piamena

Cards (24)

What are the types of PROTEIN FILAMENTS found in the cytoskeleton?
Microfilaments, intermediate filaments, and microtubules.
What is the SUBUNIT of MICROFILAMENTS?
G-actin monomers
What is the SUBUNIT of INTERMEDIATE FILAMENTS?
Anti-parallel tetramers of 2 rod-like dimers
What is the SUBUNIT of MICROTUBULES?
Heterodimers of ab tubulin
What is the OVERALL STRUCTURE of MICROFILAMENTS?
2 intertwined F-actin filaments
What is the OVERALL STRUCTURE of INTERMEDIATE FILAMENTS?
Cable of 4 intertwined protofibrils, each consisting of bundles of tetramers associated end to end.
What is the OVERALL STRUCTURE of MICROTUBULES?
Hollow tube with a wall of 13 parallel protofilaments
What is the DIAMETER of MICROFILAMENTS?
5-7 nanometers
What is the DIAMETER of INTERMEDIATE FILAMENTS?
8-10 nanometers
What is the DIAMETER of MICROTUBULES?
25 nanometers
What is the MONOMETRIC PROTEIN of MICROFILAMENTS?
Globular G-actin (42 kDa)
What is the MONOMETRIC PROTEIN of INTERMEDIATE FILAMENTS?
Various a-helical rod-like proteins (-55 kDa)
What is the MONOMETRIC PROTEIN of MICROTUBULES?
a and b tubulin (54 kDa)
What is the POLARITY of MICROFILAMENTS?
+ and - ends
What is the POLARITY of INTERMEDIATE FILAMENTS?
No apparent polarity
What is the POLARITY of MICROTUBULES?
+ and - ends
What is the RELATIVE STABILITY of MICROFILAMENTS?
Dynamic
What is the RELATIVE STABILITY of INTERMEDIATE FILAMENTS?
Stable
What is the RELATIVE STABILITY of MICROTUBULES?
Dynamic in CYTOPLASM; Stable in AXONEMES
MICROTUBULES: Radiating through cytoplasm from concentration at CENTROSOMES; AXONEMES
MICROFILAMENTS: Concentrated beneath the CELL MEMBRANE; in cell extensions like MICROVILLI
INTERMEDIATE FILAMENTS: Arrayed throughout CYTOPLASM; at DESMOSOMES; inside the nuclear envelope
MICROTUBULES: Maintain cell's shape and POLARITY; provide TRACKS for organelles and chromosome movement; move CILIA and FLAGELLA
MICROFILAMENTS: Contract and MOVE CELLS; CHANGE cell's shape; cytokinesis; cytoplasmic transport and streaming.