11,561 research outputs found
Conformal Invariance in the Long-Range Ising Model
We consider the question of conformal invariance of the long-range Ising
model at the critical point. The continuum description is given in terms of a
nonlocal field theory, and the absence of a stress tensor invalidates all of
the standard arguments for the enhancement of scale invariance to conformal
invariance. We however show that several correlation functions, computed to
second order in the epsilon expansion, are nontrivially consistent with
conformal invariance. We proceed to give a proof of conformal invariance to all
orders in the epsilon expansion, based on the description of the long-range
Ising model as a defect theory in an auxiliary higher-dimensional space. A
detailed review of conformal invariance in the d-dimensional short-range Ising
model is also included and may be of independent interest.Comment: 52pp; V2: refs added; V3: ref added, published versio
Giant FAZ10 is required for flagellum attachment zone stabilization and furrow positioning in Trypanosoma brucei
The flagellum and flagellum attachment zone (FAZ) are important
cytoskeletal structures in trypanosomatids, being required for motility,
cell division and cell morphogenesis. Trypanosomatid cytoskeletons
contain abundant high molecular mass proteins (HMMPs), but many of
their biological functions are still unclear. Here, we report the
characterization of the giant FAZ protein, FAZ10, in Trypanosoma
brucei, which, using immunoelectron microscopy, we show localizes to
the intermembrane staples in the FAZ intracellular domain. Our data
show that FAZ10 is a giant cytoskeletal protein essential for normal
growth and morphology in both procyclic and bloodstream parasite life
cycle stages, with its depletion leading to defects in cell morphogenesis,
flagellum attachment, and kinetoplast and nucleus positioning. We show
that the flagellum attachment defects are probably brought about by
reduced tethering of the proximal domain of the paraflagellar rod to the
FAZ filament. Further, FAZ10 depletion also reduces abundance of FAZ
flagellum domain protein, ClpGM6. Moreover, ablation of FAZ10
impaired the timing and placement of the cleavage furrow during
cytokinesis, resulting in premature or asymmetrical cell division
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