Proper division plane positioning is crucial for faithful chromosome segregation but also influences cell size, position, or fate [1]. In fission yeast, medial division is controlled through negative signaling by the cell tips during interphase and positive signaling by the centrally placed nucleus at mitotic entry [2-4]: the cell geometry network (CGN), controlled by the inhibitory cortical gr...

As in many other eukaryotic cells, cell division in fission yeast depends on the assembly of an actin ring that circumscribes the middle of the cell. Schizosaccharomyces pombe cdc12 is an essential gene necessary for actin ring assembly and septum formation. Here we show that cdc12p is a member of a family of proteins including Drosophila diaphanous, Saccharomyces cerevisiae BNI1, and S. pombe ...

Fission yeast cells divide by medial cleavage using an actin-based contractile ring. We have conducted a genetic screen for temperature-sensitive mutants defective in the assembly and placement of this actin ring. Six genes necessary for actin ring formation and one gene necessary for placement of the actin ring have now been identified. The genes can be further organized into different phenoty...

Chloroplast division in plant cells is orchestrated by a complex macromolecular machine with components positioned on both the inner and outer envelope surfaces. The only plastid division proteins identified to date are of endosymbiotic origin and are localized inside the organelle. Employing positional cloning methods in Arabidopsis in conjunction with a novel strategy for pinpointing the muta...

BACKGROUND Chloroplast division in plant cells occurs by binary fission, yielding two daughter plastids of equal size. Previously, we reported that two Arabidopsis homologues of FtsZ, a bacterial protein that forms a cytokinetic ring during cell division, are essential for plastid division in plants, and may be involved in the formation of plastid-dividing rings on both the stromal and cytosoli...

In this paper, we present an isomorphism between the ring of general polynomials over a division algebra D with center F and the group ring of the free monoid with [D : F ] variables over D. Using this isomorphism, we define the characteristic polynomial of any matrix over any division algebra, i.e., a general polynomial with one variable over the algebra whose roots are precisely the left eige...

We give a necessary condition for algebraicity of finite modules over the ring of formal power series. This condition is given in terms of local zero estimates. In fact we show that this condition is also sufficient when the module is a ring with some additional properties. To prove this result we show an effective Weierstrass Division Theorem and an effective solution to the Ideal Membership P...

An ultra-low power injection locked frequency divider (ILFD) is presented and demonstrated. Based on a 5-stage single ended ring oscillator, the ILFD achieves a lock range of 56% at a division ratio of 5 in the medical implant communications service (MICS) and the 433MHz ISM frequency bands. The ILFD is implemented in a 90nm CMOS process. It consumes 3 μW of power from a 1.0V supply and 100 μm ...

Lawrence I. Rothfield and Sheryl S. Justice we may beclosing in on the prey. In a recent issue of Cell, Hale and de Boer (1997) described a newly identified Department of Microbiology University of Connecticut Health Center integral membrane protein, ZipA, that emerged from a direct search for genes coding for proteins that interact Farmington, Connecticut 06030 with FtsZ. ZipA has several prop...

Lawrence I. Rothfield and Sheryl S. Justice we may beclosing in on the prey. In a recent issue of Cell, Hale and de Boer (1997) described a newly identified Department of Microbiology University of Connecticut Health Center integral membrane protein, ZipA, that emerged from a direct search for genes coding for proteins that interact Farmington, Connecticut 06030 with FtsZ. ZipA has several prop...