The slides were finally washed four times in PBS for 15 min each. needed for axial element formation during synapsis (Hollingsworth and Byers 1989; Zickler and Kleckner Toll-like receptor modulator 1999), whereas its ortholog in (2000). Conversely, some proteins appear to perform the same Toll-like receptor modulator functions in different organisms, yet have little amino acid sequence in common. For example, the transverse filament protein of the SC of (Zyp1; Higgins 2005) shares only 18C20% sequence identity and 36C40% similarity with the related protein Zip1 from (Sym 1993), Toll-like receptor modulator with Scp1 from mammals (Heyting 1996), and with C(3)G from (Page and Hawley 2004). Furthermore, you will find other proteins that look like unique to particular organisms, such as the Phs1 protein of maize, which has no significant homology to known proteins, apart from superficial resemblance to two families of helicases from fungi (Pawlowski 2004). Taken as a whole, these observations emphasize the fact that an understanding of meiosis requires an integration of our knowledge of the process in different organisms (Shaw and Moore 1998). Rye (2005). It has a nuclear genome, which is definitely replete with Toll-like receptor modulator gene duplicates and reiterated, noncoding DNA (Devos 1993; Devos and Gale 2000; Alkhimova 2004; Schulman 2004; Varshney 2004) and which is definitely 64 times the size of the compact genome of The mutant was chosen from a collection of spontaneous mutants (Sosnikhina 2005) on the basis of its mainly asynaptic phenotype and propensity to synapse chromosomes indiscriminately (Fedotova 1994; Sosnikhina 1994b). Although this mutant has a very low chiasma rate of recurrence, it forms some bivalents and characteristic sticky associations at first metaphase. Simultaneous fluorescence hybridization (FISH) with five landmark DNA probes enabled all 14 chromosomes to be identified with a high degree of confidence. This permitted for the first time an analysis of chiasmate and nonchiasmate associations at this stage, from which inferences could be drawn about the relationship between chromosome structure and pairing behavior when homology, acknowledgement, and synapsis are jeopardized by mutation. Taken collectively, the cytological and molecular data contribute to the assembly of a phenotypic identikit for this mutant and aid the reconstruction of genetic control pathways of meiosis in rye. The study also validates the power of like a model for meiosis across the divide between the monocots and the dicots. MATERIALS AND METHODS Flower material: Spontaneous synaptic mutation of winter season rye (L. 2= 2= 14) was originally isolated in 1985 from selfed F1 hybrids of crosses between individual vegetation of Trans-Caucasian weedy rye and vegetation of self-fertile inbred lines (Sosnikhina 1994a). Homozygotes for are mainly sterile and are isolated from segregating progenies of selfed heterozygotes on the basis of their aberrant meiotic phenotype, high univalency at metaphase I, and unique indiscriminate synapsis during meiotic prophase (Fedotova 1994; Sirt6 Sosnikhina 1994b). Segregating progenies analyzed in Aberystwyth originate from a single flower cultivated and selfed in 1999 in an experimental field at St. Petersburg, representing the third generation of inbreeding following an intermediate mix of one flower with Grossh. The progeny of this single plant were sown in an unheated greenhouse in Aberystwyth in October 2002 and allowed to blossom in time of year (May to June 2003). All subsequent progeny displayed a more extreme form of the phenotype (analogous to group II), which has a higher mean univalent rate of recurrence at metaphase I compared with group I (Fedotova 1994; Sosnikhina 1994b). Segregating progeny utilized for the FISH study originated from a single sib progenitor of the Aberystwyth stocks. To gain access to meiotic material for additional experiments the year round, and to standardize growth and flowering conditions, small batches of seed of segregating family members have been sown regularly since 2004, and 3-day-old seedlings were vernalized artificially for 40 days inside a dark refrigerator at 0. Following the chilly treatment, the seedlings were transferred to pots inside a Toll-like receptor modulator transgenic greenhouse and produced to maturity under 16-hr days with 60 mol/m2/sec illumination at 15, and 10 nights. Individuals with high bivalent frequencies segregating in the family members were used as settings. The spring rye strain Shkolnaya Hl [Ddw1CDominant dwarfness 1; Leningrad region, K-11575, N. I.Vavilov All-Russian Study Institute of Flower Market (VIR), St. Petersburg, Russia], which has no vernalization requirement, was also produced regularly under the same greenhouse conditions to provide an.