Exam 2 vocab repeats.txt

  1. Actin
    A family of proteins making up 5-10% of the total protein of the typical eukaryotic cell. Actin, which is 5-7 nm in diameter, is the material of which microfilaments, which perform a contractile function in the cytoskeleton, are composed. It is also present in the contractile, thin filaments of sarcomeres in muscle
  2. Tubulin
    The protein that forms the primary component of microtubules. Each unit of tubulin is a dimer with an alpha and beta subunit.
  3. Keratin
    Family of intermediate filament proteins expressed in epithelial cells. Acid and base.
  4. Desmin
    Any of various proteins found in intermediate filaments that copolymerize with vimentin to form constituents of connective tissue, cell walls, and filaments. Found in Z disc of skeletal and cardiac muscle cells.
  5. Vimentin
    The polypeptide that copolymerizes with other subunits to form the intermediate filament cytoskeleton of mesenchymal cells.
  6. Lamin A or B
    Fibrous network of intermediate filaments associated with the nucleoplasmic aspect of the inner membranes of cell nuclei, composed of polypeptides of varying molecular weights (60,000-80,000) and classified as A, B, C, and upward, on the basis of physical properties; the phosphorylation of lamins is associated with mitosis and the breakdown of the nuclear envelope.
  7. Plectin
    An intermediate filament-associated protein that links vimentin to microtubules, aiding in formation of three-dimensional intracellular lattices of cytoskeletal elements.
  8. Filaggrin
    an intermediate filament-associated protein, which is involved in cross-linking of keratin; the main constituent of keratohyalin in the granular layer of the epidermis.
  9. BPAG1
    Bullous Pemphigoid Antigen 1. Connects keratin to BPAG2 at the hemidesmosomes.
  10. Myosin
    a protein of the myofibril, occurring chiefly in the A band; with actin it forms actomyosin, which is responsible for the contractile properties of muscle.
  11. Western blot
    An assay that detects specific proteins within a protein mixture by a multistep process consisting of electrophoresis on a slab gel, transfer of the proteins on the gel to a membrane followed by identification of the specific proteins by antibody staining
  12. Kinesin
    one of three mechanochemical proteins (the other two are myosin and dynesin) associated with the cytoskeleton that converts chemical energy into mechanical energy and is the driving force for the movement of vesicles and organelles along the microtubule.
  13. Dynein
    A protein associated with motile structures that exhibits adenosine triphosphatase activity; it forms "arms" on the outer microtubules of cilia and flagella. It functions as a molecular motor.
  14. Treadmilling
    A movement mechanism in microfilaments and microtubules involving growth at one end and shortening at the other.
  15. Nucleation
    The beginning of chemical or physical changes at discrete points in a system. Used in reference to microtubule growth at the centrosome.
  16. Cytochalasin
    a drug that interfere with the formation of microfilaments and thus disrupt cellular processes dependent on those filaments.
  17. Phalloidin
    a peptide that acts by binding and stabilizing actin filaments. Used in conjunction with rhodamine to label actin filaments in the cell.
  18. Thymosin
    small protein that sequesters ATP-actin monomers. Monomer binding.
  19. Profilin
    A small protein that binds to ATP-actin (thus becoming profilactin), preventing premature polymerization of actin. Can also amplify assembly of microfilaments.
  20. ADF/cofilin
    binds ADP-actin subunits in filaments thereby promoting severing and depolymerization. Also nucleates filaments.
  21. Gelsolin
    An actin-binding protein; a Ca2+-triggered actin-filament-severing protein. Severing and copying.
  22. Nebulin
    giant protein that extends from end to end of striated muscle actin filaments. May serve as a “ruler”.
  23. Tropomyosin
    a muscle protein of the I band that inhibits contraction by blocking the interaction of actin and myosin, except when influenced by troponin.
  24. Karyokinesis
    division of the nucleus, usually an early stage in the process of cell division, or mitosis.
  25. Cytokinesis
    the division of the cytoplasm during the division of eukaryotic cells.
  26. Cytoplasmic streaming
    The streaming rotary motion of organelles and cytoplasm within certain cells and one-celled organisms.
  27. Amoeboid locomotion
    the motion seen in ameba and other cells which results from the assembly and disassembly of actin microfilaments. The assembly pushes the plasma membrane out.
  28. Microfilament
    The finest filamentous element of the cytoskeleton, having a diameter of about 5 nm and consisting primarily of actin.
  29. Microtubule
    any of the slender, tubular structures composed chiefly of tubulin, found in the cytoplasmic ground substance of nearly all cells; they are involved in maintenance of cell shape and in the movements of organelles and inclusions, and form the spindle fibers of mitosis.
  30. Intermediate filament
    family of 10-nm filaments composed of α-helical subunits.
  31. Mitotic spindle
    the fusiform figure occurring during metaphase of cell division, composed of microtubules radiating from the centrioles and connecting to the chromosomes at their centromeres.
  32. Centrosome
    A small region of cytoplasm adjacent to the nucleus that contains the centrioles and serves to organize microtubules.
  33. MTOC
    microtubule organizing center. The centrosome.
  34. Pericentriolar material
    matrix surrounding the centrioles that contains the gamma tubulin ring complexes, which nucleate microtubules.
  35. Gamma tubulin ring complex (-TuRC)
    Complex of 10 to 13 gamma-tubulin molecules and 8 associated polypeptides that nucleates microtubule assembly.
  36. Colchicine
    A drug isolated from autumn crocus that inhibits microtubules assembly by binding dissociated tubulin dimers. MT disassembly occurs.
  37. Nocodazole
    synthetic chemical that inhibits microtubules assembly by binding dissociated tubulin dimers. MT disassembly.
  38. Taxol
    Cancer chemotherapy drug isolated form the bark of the Western Yew that binds β-tubulin and stabilizes microtubules.
  39. Exchangeable/non-exchangeable GTP
    found on the tubulin dimer. The α-tubulin has a non-exchangeable GTP while the β-tubulin has an exchangeable GTP.
  40. Protofilament
    a 5-nm thick filament formed by the aggregation of tubulin dimers in the form of microtubules; a stage in the development of the microtubule. 13-15 make up a microfilament.
  41. Gene family
    a group of genes that code for the same type of protein. The actin gene family codes for the actin proteins and isoforms in various eukaryotes.
  42. Dynamic instability
    a term used to describe the assembly, disassembly and reassembly of microtubules. In the cell assemble, a catastrophe occurs, the MT disassemble, recovery, reassembly.
  43. Tau
    A protein that associates with microtubules; tau accelerates tubulin polymerization and stabilizes microtubules; tau is also found in the plaque observed in patients with Alzheimer disease and in cerebral neurons in other neurodegenerative disorders.
  44. MAP2/MAP4
    Microtubule associated proteins in the tau family.
  45. Katanin
    AAA ATPase that uses energy from ATP hydrolysis to sever microtubules.
  46. CLIP170
    Protein that concentrates on plus ends of growing microtubules; involved in transport of membranes and behavior of microtubules at kinetochores.
  47. Centriole
    Usually a component of the centrosome. Often occurring in pairs, centrioles are associated with cell division. They are tiny cylinders positioned at right angles to each other, with walls consisting of nine bundles of fine tubules, three tubules to a bundle. The precise function of centrioles is still a mystery, but they appear to aid in the formation of the spindle that develops during mitosis.
  48. Basal body
    an organelle formed from a centriole, and a short cylindrical array of microtubules. It is found at the base of a eukaryotic cilia or flagellum and serves as a nucleation site for the growth of the axoneme microtubules.
  49. Poison protein
    identified in intermediate filament mutants. A defective (mutant) protein co-assembles with or interferes with the assembly of the normal endogenous protein resulting in a mutant phenotype. This co-assembly phenotype is more severe that the null/knockout phenotype. This is the hallmark of a “poison” protein.
  50. Transgenic
    inserting the DNA of interest into another organism.
  51. DIC
    • Differential interference contrast microscopy (DIC), or Nomarski microscopy, is an optical microscopy technique used to enhance the contrast in unstained, transparent samples. DIC works on the to gain information about the optical density of the sample, to see otherwise invisible features. A relatively complex lighting scheme produces an image with the object appearing black to white on a grey background.
    • Fluorescence microscopy photobleaching - the photochemical destruction of a fluorescent molecule.
  52. Photoactivation
    activation of a fluorescent molecule.
Card Set
Exam 2 vocab repeats.txt
cell bio exam 2 vocab