Dyneins are a group of microtubule-activated ATPases that serve to convert chemical energy into mechanical energy. They have been divided into two large subgroups, namely the axonemal and cytoplasmic dyneins. Cytoplasmic dynein has been implicated in a variety of other forms of intracellular motility, including retrograde axonal transport, protein sorting between apical and basolateral surfaces, and redistribution of organelles like endosomes and lysosomes. Our report is the first chromosomal localization of the human ctyoplasmic dynein heavy chain (DNECL). 7 refs., 1 fig.
[Show abstract][Hide abstract] ABSTRACT: The finding of men with living but immotile sperm tails has initiated a search for the cause of the disorder. The sperm tails were found to lack dynein arms or to have some other ultrastructurally visible defect and the cilia were found to have the same defects. The disorder was hence named the immotile-cilia syndrome. Two more groups with the same clinical symptoms were later found, characterized by ciliary dysmotility or ciliary aplasia. In each group there are several subgroups. Many of the affected persons have situs inversus totalis; in some subgroups the incidence of situs inversus is probably 50%; there is, thus, a random determination of visceral asymmetry. Five hypotheses have been forwarded that attempt to explain the connection between ciliary defects and loss of laterality control. Support for, or evidence against, these five hypotheses have been sought in some animal models of the syndrome. Whereas immotile-cilia syndrome in dogs and pigs is very similar to the human one, an animal model in the rat differs from the human syndrome in that mainly the males are affected. Two animal models in the mouse differ in that one has ciliary defects but no increased incidence of situs inversus and the other has a random determination of visceral laterality and no ciliary defects. The connection between ciliary defects and random determination of laterality remains enigmatic.
The International Journal of Developmental Biology 11/1995; 39(5):839-44. · 1.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report the molecular and genetic characterization of the cytoplasmic dynein light-chain gene, ddlc1, from Drosophila melanogaster. ddlc1 encodes the first cytoplasmic dynein light chain identified, and its genetic analysis represents the first in vivo characterization of cytoplasmic dynein function in higher eucaryotes. The ddlc1 gene maps to 4E1-2 and encodes an 89-amino-acid polypeptide with a high similarity to the axonemal 8-kDa outer-arm dynein light chain from Chlamydomonas flagella. Developmental Northern (RNA) blot analysis and ovary and embryo RNA in situ hybridizations indicate that the ddlc1 gene is expressed ubiquitously. Anti-DDLC1 antibody analyses show that the DDLC1 protein is localized in the cytoplasm. P-element-induced partial-loss-of-function mutations cause pleiotropic morphogenetic defects in bristle and wing development, as well as in oogenesis, and hence result in female sterility. The morphological abnormalities found in the ovaries are always associated with a loss of cellular shape and structure, as visualized by a disorganization of the actin cytoskeleton. Total-loss-of-function mutations cause lethality. A large proportion of mutant animals degenerate during embryogenesis, and the dying cells show morphological changes characteristic of apoptosis, namely, cell and nuclear condensation and fragmentation, as well as DNA degradation. Cloning of the human homolog of the ddlc1 gene, hdlc1, demonstrates that the dynein light-chain 1 is highly conserved in flies and humans. Northern blot analysis and epitope tagging show that the hdlc1 gene is ubiquitously expressed and that the human dynein light chain 1 is localized in the cytoplasm. hdlc1 maps to 14q24.
Stephanie K See, Sascha Hoogendoorn, Andrew H Chung, Fan Ye, Jonathan B Steinman, Tomoyo Sakata-Kato, Rand M Miller, Tommaso Cupido, Ruta Zalyte, Andrew P Carter, Maxence V Nachury, Tarun M Kapoor, James K Chen,
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.