RNAi screen using dsRNA made from templates generated with primers directed against this gene causes defects in spindle shape and unfocused spindle microtubules when assayed in S2 cells. This phenotype can be observed when the screen is performed with or without Cdc27 dsRNA.

S2 cells transfected with dsRNA made from templates generated with primers directed against this gene show detachment of centrosomes from the spindle poles, resulting in a slight increase of spindle size.

dsRNA made from templates generated with primers directed against this gene tested in RNAi screen for effects on Kc167 and S2R⁺ cell morphology.

Spindle pole movements in embryos are directed by a temporally coordinated balance of forces generated by three mitotic motors; cytoplasmic dynein, Klp61F and ncd. Dynein acts to move the poles apart throughout mitosis, and this activity is augmented by Klp61F after the fenestration of the nuclear envelope, which occurs at the onset of prometaphase. ncd generates forces that pull the poles together between interphase and metaphase, antagonising the activity of both cytoplasmic dynein and Klp61F and serving as a brake for spindle assembly.

The ncd tail domain can promote microtubule assembly and stability.

Mutants show disruption of chromosome segregation in meiosis whether or not they have undergone exchange and without any direct effect on the level of exchange.

The inhibition of Klp61F function (via injected antibodies) embryos inhibits the formation of bipolar metaphase spindles.

Analysis of Khc-ncd fusion proteins indicates that residues or regions contributing to motor polarity are present in the ncd neck region. The neck-motor junction is also critical for ncd minus-end movement.

ncd is necessary for chromosome segregation and can interact specifically with the centromere. ncd requires only centromeric sequences for its action in chromosome segregation.

AMPPNP (a non-hydrolyzable ATP analog) is hydrolysed by the motor domain of ncd with a slow turnover. Turnover cannot be accelerated by microtubules.

Medium-resolution three-dimensional structure of microtubules interacting with two functional dimeric motors with opposite directionality (Khc and ncd) is determined.

ncd microtubule motor performs an active role during mitosis in early embryos. The motor acts to maintain centrosome integrity and attachment to nuclei, contributes to midbody stability and helps to prevent chromosome loss during the early mitotic divisions.

ncd protein is required for normal spindle assembly kinetics and stabilisation of the spindle during metaphase arrest. Immunolocalisation analyses demonstrate that ncd is associated with spindle microtubules. Results suggest that microtubule binding by ncd promotes assembly of a stable bipolar spindle in the absence of typical microtubule organising centres (MTOCs).

Missense mutation at residue 556, part of the motor domain, allows translocation on microtubules but at a reduced velocity relative to wild type. This provides evidence that the reduced rate of translocation is caused by altered binding of the mutant motor to microtubules.

The crystal structure of the MgADP complex of the ncd motor domain is determined to 2.5A by X ray crystallography and compared to the Khc motor domain. The domains are similar in structure and locations of conserved surface amino acids suggest the motors share a common microtubule-binding site. Structural and functional comparisons indicate the NTPases may have a similar strategy of changing conformation between NTP and NDP states.

ncd and Khc differ in their initial, weak binding to microtubules which causes the proteins to move in opposite directions. The nature of a structural bias that may serve as a determinant of motor polarity is not clear, results suggest the microtubule binding site may determine direction.

Neutron scattering study reveals the overall shape of the motor domain is not the major determinant of the directionality of the movement along microtubules.

Three dimensional reconstruction of the monomeric motor domain at the carboxy terminus of ncd is presented (FBrf0083611).

A three dimensional map of tubulin sheets decorated with monomeric recombinant ncd motor domains has been calculated by negative-stain electron microscopy and image analysis. Comparisons with a control structure of tubulin alone reveals that each motor domain binds to the crest of a single protofilament making extensive contacts with both the α and β tubulin monomers, binding of the motor domain results in significant conformational change in both the tubulin monomers.

ADP release is the rate-limiting step for ATP turnover for ncd protein.

The motile and enzymatic properties of the ncd protein have been analysed.

Mixtures of ncd motor domain and full length ncd protein treated with the zero-length cross linker EDC generates covalently cross linked products of ncd with βTub56D and ncd with αTub84B. These results indicate that the ncd motor domain interacts with both βTub56D and αTub84B.

Identified as a 90kD polypeptide in an ATP MAPs 1-24 hour embryonic fraction.

The sequence of the ncd protein has been compared with the sequences of a variety of kinesin family proteins.

Despite ncds reversed directionality relative to kinesin, ncd has very similar ATPase kinetics to kinesin and an identical mode of coupling to microtubule binding.

Encoded protein consists of 3 domains: a basic, proline-rich N terminal tail, a central α-helical coiled coil stalk, and a C terminal motor. Expression of different regions of ncd in bacteria indicates that ncd consists of three domains, a basic, proline rich N-terminal tail, a central alpha-helical coiled coil stalk and a C-terminal motor domain. N terminus proteins bundle microtubules in motility assays and show ATP-independent binding to microtubule in solution. C terminus proteins retain the ability to hydrolyse ATP in solution and the stalk region is important for dimerisation.

N-terminal truncation of the 'tail' region of the protein identifies a weak binding state of the ncd motor. This weak binding state may be important in the mechanochemical function of the ncd motor protein.

A series of truncated kinesin heavy chain and ncd proteins were generated and assayed for movement along microtubules in vitro: conserved domain of both proteins has microtubule motor activity, and direction of movement is intrinsic to conserved motor domain.

Mutations at ncd disrupt meiotic spindle formation.

ncd protein localizes to both the mitotic and meiotic spindle.

ncd has been cloned and characterised.

The behaviour of the ncd protein has been studied in vitro, showing that ncd is a minus end-directed microtubule motor.

ncd is a minus-end directed microtubule motor. It also generates torque, causing microtubules to rotate as they move forward in in vitro motility assays.

The 'ca^nd' locus has been found to be two closely linked but separate genes, ca and ncd.

Disjunction in homozygous females abnormal; incidence of nondisjunction of all chromosome pairs in the first meiotic division and of meiotic and early-cleavage mitotic loss of maternally inherited chromosomes is high. X-chromosome recombination normal among both regular and exceptional progeny. Behavior of nonhomologues correlated; doubly disomic and doubly nullosomic ova more frequent than expected (Davis, 1969). Similar in action to ca of D.simulans (Sturtevant, 1929). Two thirds of mitotic loss of chromosomes in progeny of ncd mothers takes place in the first zygotic division; one third takes place subsequently. The majority of X-chromosome loss (85-95%) is of the maternally inherited X but there is also appreciable loss of the paternally inherited X as well (Sequeira et al., 1989). Somatic loss of X and 4 correlated (Portin, 1978). Cytological description of meiotic behavior in D.simulans ca females (Wald, 1936) includes abnormal first meiotic spindle, second meiotic arrest, and dispersal of chromosomes into multiple micronuclei; micronuclei also observed in ncd females (Roberts, 1962). Spindles frequently multipolar in first meiotic division (Puro) and in early-embryo nuclear divisions and nuclei remain close together in center of egg (Kimble and Sandstedt, 1981). Kimble and Church (1981) observed four classes of metaphase 1 configurations: (1) two or more spindles (2) abnormally wide spindles with widely separated bivalents (3) unipolar spindles and (4) normal spindles; the first three comprise 80% of configurations. Approximately 20% of eggs of ncd¹ females asymmetrical or with more than two appendages (Kimble and Church, 1981). Hinton and McEarchen (1963) reported a haploid-diploid mosaic. ncd ovaries transplanted into normal host behave autonomously (Roberts, 1962). Chromosome segregation normal in ncd males.