The evolutionarily conserved transcription factor PRDM12 controls sensory neuron development and pain perception

PR homology domain-containing member 12 (PRDM12) is a highly evolutionary conserved member of the Prdm family of transcription factors that play essential roles in many cell fate decisions. In human, PRDM12 coding mutations have been recently identified in several patients with hereditary sensory and autonomic neuropathy (HSAN) (submitted elsewhere). Here we show that PRDM12 is involved in sensory neurogenesis in Xenopus and that several of the human Prdm12 mutants show altered structure, subcellular localization and function. In Drosophila, we demonstrate that the sensory neuron specific RNAi knockdown of the Prdm12 ortholog Hamlet induces impaired nociception and that a similar phenotype is observed in hypomorph hamlet mutants. In human fibroblasts of patients with PRDM12 mutations, we identified additional possible downstream target genes including thyrotropin-releasing hormone degrading enzyme (TRHDE). Knock-down of fly TRHDE in sensory neurons resulted in altered nociceptive neurons and impaired nociception. Collectively, these findings provide the first evidence showing that Prdm12 plays an important role in sensory neuron development. They also suggest that it has a critical evolutionarily conserved role in pain perception via modulation of the TRH signaling pathway.

Ill-Posedness, Regularization and Number of Degrees of Freedom

info:eu-repo/semantics/published

Superresolution and number of degrees of freedom in inverse diffraction with subwavelength sources

info:eu-repo/semantics/published

Number of degrees of freedom in inverse diffraction

The problem of inverse diffraction from plane to plane is considered in the case where a finite aperture exists in the boundary plane. Singular values and singular functions for the problem are introduced, and the number of degrees of freedom is defined in terms of the distribution of the singular values. Numerical computations are presented for the one-dimensional problem, and it is shown that the effect of evanescent waves disappears at a distance of approximately one wavelength from the boundary plane, even when the dimension of the slit is comparable with the wavelength of the diffracted field. © 1983 Taylor & Francis Group, LLC.

Consistent couplings between fields with a gauge freedom and deformations of the master equation

The antibracket in the antifield-BRST formalism is known to define a map Hp × Hq → Hp + q + 1 associating with two equivalence classes of BRST invariant observables of respective ghost number p and q an equivalence class of BRST invariant observables of ghost number p + q + 1. It is shown that this map is trivial in the space of all functionals, i.e. that its image contains only the zeroth class. However, it is generically non-trivial in the space of local functionals. Implications of this result for the problem of consistent interactions among fields with a gauge freedom are then drawn. It is shown that the obstructions to constructing non-trivial such interactions lie precisely in the image of the antibracket map and are accordingly non-existent if one does not insist on locality. However consistent local interactions are severely constrained. The example of the Chern-Simons theory is considered. It is proved that the only consistent, local, Lorentz covariant interactions for the abelian models are exhausted by the non-abelian Chern-Simons extensions. © 1993.