; R o o t E n t r y F C o m p O b j b W o r d D o c u m e n t - O b j e c t P o o l / 0 1 2 3 4 5 6 7 8 9 F Microsoft Word 6.0 Document MSWordDoc Word.Document.6 ; 95-05670 R. Kelly Dawe This is a cytogenetic study of meiosis, or gamete production, in maize, focusing on the structure, the kinetochore, where the meiotic spindle attaches to the chromosome. In the post-doctoral work which serves as a basis for this proposal, image processing of fluorescent chromosomes using deconvolution software now comercially available resulted in more accurate timing of when chromosome pairing occurs during meiosis and a new cytological map for maize chromosome at the start of meiosis. Using mutant maize inbred lines, evidence was obtained to support the hypothesis that the kinetichore is a prerequisite to spindle formation in meiosis and that kinetochore-like structures appear in an inbred line with an abnormal chromosome 10. Dr Dawe will now pursue higher resolution imaging in order to achieve 3D reconstruction of the kinetochore itself. Antibodies which have been used to fluorescently tag the kinetochore will now be used to map its substructure. The proteins which code for these kinetochore proteins will be cloned and monoclonal antibodies prepared. These reagent s and select inbred lines will be used to map the structural differences between the meiotic and mitotic kinetochores, between kinetochores involved in reductional vs. equatorial division, and between the normal kinetochore and the kinetochore-like structure found in a line with abnomral chromosome 10. %%% The meiotic kinetochore has historically provided important insights into the broader functions of the kinetochore, one of the most important structures on the chromosome. It has been shown to bind telomeric DNA, hold sister chromatids together, bind to spindle microtubules, interact with molecular motors on the spindle,and produce a signal that is used as a cell cycle check point. Insight into the way it does this will come with this study which dissects the components of the kinetochore and shows how they interact and change spacially with time. *** ; Oh +' 0 $ H l S u m m a r y I n f o r m a t i o n ( . D h R:WWUSERTEMPLATENORMAL.DOT 95-05670 Una Solomon Una Solomon @ O @ @ O @ F # Microsoft Word 6.0 2 ; e 3 e - p p p p p p p u 1 7 W T 3 u p u p p p p p p p p i 95-05670 R. Kelly Dawe This is a cytogenetic study of meiosis, or gamete production, in maize, focusing on the structure, the kinetochore, where the meiotic spindle attaches to the chromosome. In the post-doctoral work which serves as a basis for this proposal, image processing of fluorescent chromosomes using deconvolution software now comercially available resulted in more accurate timing of when chromosome pairing occurs during meiosis and a new cytological map for maize chromosome at the start of meiosis. Using mutant maize inbred lines, evidence was obtai