Chromatin remodeling and histone modifications facilitate access of transcription factors to DNA by promoting the unwinding and destabilization of histone-DNA interactions. We present DPF3, a new epigenetic key factor for heart and muscle development characterized by a double PHD finger. DPF3 is associated with the BAF chromatin remodeling complex and binds methylated and acetylated lysine residues of histone 3 and 4. Thus, DPF3 may represent the first plant homeodomains that bind acetylated lysines, a feature previously only shown for the bromodomain. During development Dpf3 is expressed in the heart and somites of mouse, chicken, and zebrafish. Morpholino knockdown of dpf3 in zebrafish leads to incomplete cardiac looping and severely reduced ventricular contractility, with disassembled muscular fibers caused by transcriptional deregulation of structural and regulatory proteins. Promoter analysis identified Dpf3 as a novel downstream target of Mef2a. Taken together, DPF3 adds a further layer of complexity to the BAF complex by representing a tissue-specific anchor between histone acetylations as well as methylations and chromatin remodeling. Furthermore, this shows that plant homeodomain proteins play a yet unexplored role in recruiting chromatin remodeling complexes to acetylated histones.[Keywords: Heart and skeletal muscle development and function; PHD finger; BAF chromatin remodeling complex; SMARCD3-BAF60; acetylated and methylated histones; Mef2] Supplemental material is available at http://www.genesdev.org.

The present study provides evidence that tinnitus and psychological comorbidity may play an important role in the rehabilitation of CI patients, and that there is a correlation between HRQoL and these parameters. In addition to hearing tests, tinnitus, stress, and psychological comorbidity should be assessed using validated questionnaires before and after CI. This will help to improve the rehabilitation process.

The present study provides evidence that cochlear implantation constitutes a very successful procedure of auditory rehabilitation, even for patients aged ≥70 years. In addition, elderly patients benefit from implantation, with increased quality of life and reduced tinnitus and stress.

The present study provides evidence that the second CI leads to further increase in quality of life and reduction of tinnitus annoyance in addition to improvement of auditory abilities as compared with the first CI. Patients with bilateral CIs benefit from additional positive effects in all these fields.

Tissue morphogenesis and cell sorting are major forces during organ development. Here, we characterize the process of tissue morphogenesis within the zebrafish lateral line primordium, a migratory sheet of cells that gives rise to the neuromasts of the posterior lateral line organ. We find that cells within this epithelial tissue constrict actin-rich membranes and enrich apical junction proteins at apical focal points. The coordinated apical membrane constriction in single Delta D-positive hair cell progenitors and in their neighbouring prospective support cells generates cellular rosettes. Live imaging reveals that cellular rosettes subsequently separate from each other and give rise to individual neuromasts. Genetic analysis uncovers an involvement of Lethal giant larvae proteins in the maturation of apical junction belts during cellular rosette formation. Our findings suggest that apical constriction of cell membranes spatially confines regions of strong cell-cell adhesion and restricts the number of tightly interconnected cells into cellular rosettes, which ensures the correct deposition of neuromasts during morphogenesis of the posterior lateral line organ.

Dermal dendritic cells (DCs) play a central role in the immunopathology of psoriasis. We previously identified slanDCs as pro-inflammatory TNF-α, IL-23- and IL-12-producing DCs in human blood and as prominent inflammatory dermal TNF-α secreting and CD11c-positive DC subset in psoriasis. Here, we ask for the effects of TNF-α-inhibition on inflammatory slanDCs in skin and blood of 10 patients with psoriasis during 24 weeks of treatment with etanercept. Treatment with etanercept reduced the frequency of dermal slanDCs but did not induce apoptosis as determined by lack of increased active caspase-3-expression. In parallel, we found increased frequencies of slanDCs in blood which expressed lower levels of HLA-DR. Stimulating slanDCs isolated from the blood of healthy donors in vitro induced a strong production of IL-1β, IL-6, IL-23 and IL-12p70. This capacity was efficiently reduced in the presence of etanercept, thereby indicating that TNF-α is an autocrine stimulus for maturation and pro-inflammatory cytokine production of slanDCs. In vivo, we noticed that treatment with etanercept did reduce the number of dermal slanDCs in parallel to the overall expression of TNF-α and IL-23p19. However, successful treatment did not down-regulated the percentage of dermal slanDCs that stained positive for TNF-α and IL-23p19 indicating that remaining slanDCs kept their pro-inflammatory capacity. This study provides novel insights into the immune regulatory properties of etanercept at the level of inflammatory slanDCs in vivo in skin and blood as well as in vitro.

No abstract

BackgroundThe regeneration of peripheral nerve is associated with a change in the alternative splicing of the fibronectin primary gene transcript to re-express embryonic isoforms containing a binding site for α4β1 integrins that promote neurite outgrowth. Here we use PC12 cells to examine the role of the interaction between paxillin and the α4 integrin cytoplasmic domain in neurite outgrowth.ResultsExpression of α4 with mutations in the paxillin-binding domain reduced neurite outgrowth on recombinant embryonic fibronectin fragments relative to wild type α4. Over-expression of paxillin promoted neurite outgrowth while a mutant isoform lacking the LD4 domain implicated in the regulation of ARF and Rac GTPases was less effective. Optimal α4-mediated migration in leucocytes requires spatial regulation of α4 phosphorylation at Ser988, a post-translational modification that blocks paxillin binding to the integrin cytoplasmic domain. In keeping with this α4(S988D), which mimics phosphorylated α4, did not promote neurite outgrowth. However, α4 was not phosphorylated in the PC12 cells, and a non-phosphorylatable α4(S988A) mutant promoted neurite outgrowth indistinguishably from the wild type integrin.ConclusionWe establish the importance of the α4 integrin-paxillin interaction in a model of axonal regeneration and highlight differing dependence on phosphorylation of α4 for extension of neuronal growth cones and migration of non-neural cells.