Analyses of Dynein Heavy Chain Mutations Reveal Complex Interactions Between Dynein Motor Domains and Cellular Dynein Functions

    Authors

    S. Sivagurunathan; R. R. Schnittker; D. S. Razafsky; S. Nandini; M. D. Plamann;S. J. King

    Comments

    Authors: contact us about adding a copy of your work at STARS@ucf.edu

    Abbreviated Journal Title

    Genetics

    Keywords

    MICROTUBULE PLUS-ENDS; FAST AXONAL-TRANSPORT; RETROGRADE ENDOSOME; MOTILITY; NUCLEOTIDE-BINDING SITES; CYTOPLASMIC DYNEIN; NEUROSPORA-CRASSA; DYNACTIN COMPLEX; NUCLEAR-DISTRIBUTION; MITOTIC; SPINDLE; ASPERGILLUS-NIDULANS; Genetics & Heredity

    Abstract

    Cytoplasmic dynein transports cargoes for a variety of crucial cellular functions. However, since dynein is essential in most eukaryotic organisms, the in-depth study of the cellular function of dynein via genetic analysis of dynein mutations has not been practical. Here, we identify and characterize 34 different dynein heavy chain mutations using a genetic screen of the ascomycete fungus Neurospora crassa, in which dynein is nonessential. Interestingly, our studies show that these mutations segregate into five different classes based on the in vivo localization of the mutated dynein motors. Furthermore, we have determined that the different classes of dynein mutations alter vesicle trafficking, microtubule organization, and nuclear distribution in distinct ways and require dynactin to different extents. In addition, biochemical analyses of dynein from one mutant strain show a strong correlation between its in vitro biochemical properties and the aberrant intracellular function of that altered dynein. When the mutations were mapped to the published dynein crystal structure, we found that the three-dimensional structural locations of the heavy chain mutations were linked to particular classes of altered dynein functions observed in cells. Together, our data indicate that the five classes of dynein mutations represent the entrapment of dynein at five separate points in the dynein mechanochemical and transport cycles. We have developed N. crassa as a model system where we can dissect the complexities of dynein structure, function, and interaction with other proteins with genetic, biochemical, and cell biological studies.

    Journal Title

    Genetics

    Volume

    191

    Issue/Number

    4

    Publication Date

    1-1-2012

    Document Type

    Article

    Language

    English

    First Page

    1157

    Last Page

    U181

    WOS Identifier

    WOS:000309000500010

    ISSN

    0016-6731

    Share

    COinS