Cell Bio: Cytoskeleton and Cytoplasm Flashcards
Cytoskeletal filaments from smallest to largest
- microfilaments
- intermediate filaments
- microtubules
Two components that make up mictrotubules
Alpha and beta tubulin
B tubule is oriented towards + or - end of MT?
+ end, one distal to nucleus
Dynein moves which way
retrograde (from + to - ends)
Kinesin moves which way
anterograde ( - to + end)
Cilia are important in what three places in body
- respiratory tract
- paranasal sinuses
- fallopian tubes
What structure links peripheral 9 doublets in the 9+2 arrangement of microtubules in a cilia?
Axonemal dynein (ATPase that causes bending of cilia)
What disease results from axonemal dynein arm defect?
Primary ciliary dyskinesis, aka Kartagener’s Syndrome
Main 4 issues in Kartagener’s syndrome?
- bronchiectasis
- chronic sinusitis
- infertility
- situs inversus (50% of cases)
* bronchiectasis + chronic sinusitis + situs inversus is pretty diagnostic; situs inversus b/c cilia important in organ placement during development
What intermediate filament is present in connective tissue ( fibroblasts, leukocytes, endothelium) that can be stained for? What CA can the stain be useful in detecting?
Vimentin–> stains can help ID sarcomas
What int. filament is found in muscle cells? Stains can help ID what CA?
Desmin–> myosarcomas (rhabdomyosarcoma, leiomyosarcomas, etc.)
What int. filament can be stained for in epithelial cells? What CA?
Cytokeratin–> carcinomas (cancers of epithelial cell origin)
What int. filament is found in glial cells? CA stains?
GFAP (glial fibrillary acid proteins)–> astrocytomas (glioblastoma)
What int. filament is found in neurons?
Peripherin
What int. filament is found specifically in the axons within neurons? CA?
Neurofilaments–> neuroblastomas (in adrenal medulla in kids)
*What int. filaments are found in the nuclear envelope and the DNA within?
Laminins (A, B, C types)
What two dz can result form mutated laminins?
- Progeria (early aging of cells, wrinkly skin on 5 y.o.)
2. Muscular dystrophy
What structures allow for coordinatd movement of cilia on different cells?
Gap junctions
What are 5 drugs/ drug classes that interfere with microtubule function?
- Vinca alkyloids –> Vincristine, Vinblastine
- Taxanes –> Paclitaxel, Docetaxel
- Benzimidazoles –> Mebendazole, Albendazole, Thio-
- Griseofulvin–> antifungal
- Colchicine
What disease results from impaired microtubule-dependent sorting of endosomal proteins in late multivesicular endosomes?
Chediak-Higashi syndrome–> due to mutation in lysosomal trafficking regulator gene (LYST); recurrent pyogenic infections, partial albinism, peripheral neuropathies
3 lysosomal storage dz
- Gaucher
- Niemann-Pick
- Tay-Sachs