Interleukin 16 and CCL17/thymus and activation-regulated chemokine in patients with aspirin-exacerbated respiratory disease.

BACKGROUND: Interleukin (IL) 16 and thymus and activation-regulated cytokine (TARC) are chemoattractant cytokines for eosinophils and TH2 cells. Differential levels of these components in aspirin-exacerbated respiratory disease (AERD) and allergic rhinitis with asthma (ARwA) may be related to a different inflammatory response in both asthma phenotypes. OBJECTIVE: To assess the nasal lavage immunoreactivity of IL-16 and TARC cytokines. METHODS: We used multienzyme-linked immunosorbent assays to detect IL-5, IL-13, IL-16, IL-33, I-309/CCL1, TARC/CCL17, monocyte-derived chemokine/CCL22, periostin, and eosinophil cationic protein levels in nasal lavages from patients with AERD and patients with ARwA. RESULTS: The IL-13, IL-16, TARC, and periostin levels were significantly higher in patients with AERD compared with those of patients with ARwA. Correlation analysis of mediator levels in AERD revealed a possible role of IL-16 and TARC in eosinophil recruitment and activation. CONCLUSION: IL-16, TARC, and periostin distinguish between patients with AERD and those with ARwA. These mediators, taken together rather than individually, may comprise good specific nasal markers in patients with AERD. The effects of IL-16 and TARC on TH1, TH2, and T-regulatory cell functions in AERD cannot be disregarded.

The Adenylate-Forming Enzymes AfeA and TmpB Are Involved in Aspergillus nidulans Self-Communication during Asexual Development.

Aspergillus nidulans asexual sporulation (conidiation) is triggered by different environmental signals and involves the differentiation of specialized structures called conidiophores. The elimination of genes flbA-E, fluG, and tmpA results in a fluffy phenotype characterized by delayed conidiophore development and decreased expression of the conidiation essential gene brlA. While flbA-E encode regulatory proteins, fluG and tmpA encode enzymes involved in the biosynthesis of independent signals needed for normal conidiation. Here we identify afeA and tmpB as new genes encoding members the adenylate-forming enzyme superfamily, whose inactivation cause different fluffy phenotypes and decreased conidiation and brlA expression. AfeA is most similar to unknown function coumarate ligase-like (4CL-Lk) enzymes and consistent with this, a K544N active site modification eliminates AfeA function. TmpB, identified previously as a larger homolog of the oxidoreductase TmpA, contains a NRPS-type adenylation domain. A high degree of synteny in the afeA-tmpA and tmpB regions in the Aspergilli suggests that these genes are part of conserved gene clusters. afeA, tmpA, and tmpB double and triple mutant analysis as well as afeA overexpression experiments indicate that TmpA and AfeA act in the same conidiation pathway, with TmpB acting in a different pathway. Fluorescent protein tagging shows that functional versions of AfeA are localized in lipid bodies and the plasma membrane, while TmpA and TmpB are localized at the plasma membrane. We propose that AfeA participates in the biosynthesis of an acylated compound, either a p-cuomaryl type or a fatty acid compound, which might be oxidized by TmpA and/or TmpB, while TmpB adenylation domain would be involved in the activation of a hydrophobic amino acid, which in turn would be oxidized by the TmpB oxidoreductase domain. Both, AfeA-TmpA and TmpB signals are involved in self-communication and reproduction in A. nidulans.

Identification of Dp71 Isoforms Expressed in PC12 Cells: Subcellular Localization and Colocalization with ß-Dystroglycan and α1-Syntrophin.

Several dystrophin Dp71 messenger RNA (mRNA) alternative splice variants have been described. According to the splicing of exon 78 or intron 77, Dp71 proteins are grouped as Dp71d, Dp71f, and Dp71e, and each group has a specific C-terminal end. In this study, we explored the expression of Dp71 isoforms at the complementary DNA (cDNA) level and the subcellular localization of recombinant Myc-Dp71 proteins in PC12 cells. We determined that PC12 cells express Dp71a, Dp71c, Dp71ab, Dp71e, and Dp71ec mRNA splice variants. In undifferentiated and nerve growth factor-differentiated PC12 Tet-ON cells, Dp71a, Dp71ab, and Dp71e were found to localize and colocalize with ß-dystroglycan and α1-syntrophin in the periphery/cytoplasm, while Dp71c and Dp71ec were mainly localized in the cell periphery and showed less colocalization with ß-dystroglycan and α1-syntrophin. The levels of Dp71a, Dp71e, and Dp71ec were increased in the nucleus of differentiated PC12 Tet-ON cells compared to undifferentiated cells. Dp71 isoforms were also localized in neurite extensions and growth cones.

EF-hand domains are involved in the differential cellular distribution of dystrophin Dp40.

Dp40 is the shortest DMD gene product that has been reported to date. It is encoded by exons 63-70, a region required for a ß-dystroglycan interaction. Its expression has been identified in rat, mouse, and human; however, its function remains unknown. To explore the expression of Dp40 transcript and subcellular localization of epitope-tagged Dp40 proteins, RT-PCR and immunofluorescence assays were performed in PC12 cells. The expression of Dp40 mRNA was found in undifferentiated and nerve growth factor-differentiated PC12 cells. According to immunofluorescence analyses, the recombinant protein Dp40 was mainly localized in the cell periphery/cytoplasm of undifferentiated and differentiated PC12 cells, a small amount of this protein is localized to the nucleus of differentiated cells. With the aim to identify the amino acids involved in the nuclear localization of Dp40, an in silico analysis was performed and it predicted that prolines 93 and 170, located within EF1 and EF2-hand domains, are involved in the nuclear localization of this protein. This prediction was confirmed by site-directed mutagenesis, the Dp40-L93P mutant was localized to the nucleus and cell periphery, while Dp40-L170P and Dp40-L93/170P showed mainly a nuclear localization. Dp40 co-localizes with ß-dystroglycan and the co-localization score was statistically reduced in Dp40-L93P, Dp40-L170P and Dp40-L93/170P mutants.

In silico analyses of dystrophin Dp40 cellular distribution, nuclear export signals and structure modeling.

Dystrophin Dp40 is the shortest protein encoded by the DMD (Duchenne muscular dystrophy) gene. This protein is unique since it lacks the C-terminal end of dystrophins. In this data article, we describe the subcellular localization, nuclear export signals and the three-dimensional structure modeling of putative Dp40 proteins using bioinformatics tools. The Dp40 wild type protein was predicted as a cytoplasmic protein while the Dp40n4 was predicted to be nuclear. Changes L93P and L170P are involved in the nuclear localization of Dp40n4 protein. A close analysis of Dp40 protein scored that amino acids (93)LEQEHNNLV(101) and (168)LLLHDSIQI(176) could function as NES sequences and the scores are lost in Dp40n4. In addition, the changes L93/170P modify the tertiary structure of putative Dp40 mutants. The analysis showed that changes of residues 93 and 170 from leucine to proline allow the nuclear localization of Dp40 proteins. The data described here are related to the research article entitled "EF-hand domains are involved in the differential cellular distribution of dystrophin Dp40" (J. Aragón et al. Neurosci. Lett. 600 (2015) 115-120) [1].

TmpA, a member of a novel family of putative membrane flavoproteins, regulates asexual development in Aspergillus nidulans.

Asexual reproduction (conidiation) in Aspergillus nidulans is induced by environmental signals like exposure to air or nutrient starvation, and depends on brlA gene activation. The study of 'fluffy' mutants showing delayed asexual development and reduced brlA expression has defined the fluG pathway, involved in regulation of this differentiation process. Genetic characterization of a 'fluffy' mutant identified tmpA as a new gene involved in regulation of conidiation. TmpA defines a new family of putative transmembrane proteins of unknown function, widespread in filamentous fungi and plants, with homologues showing similarity to non-ribosomal peptide synthetases. The deletion of tmpA resulted in decreased brlA expression and conidiation in air-exposed colonies. This defect was suppressed when DeltatmpA mutants were grown next to wild-type or DeltafluG mutant colonies, even without direct contact between hyphae. In liquid culture, tmpA was essential for conidiation induced by nitrogen but not by carbon starvation, whereas the overexpression of different tmpA tagged alleles resulted in conidiation. The overexpression of fluG-induced conidiation independently of tmpA and DeltatmpADeltafluG double mutants showed an additive 'fluffy' phenotype, indicating that tmpA and fluG regulate asexual sporulation through different pathways. TmpA and its homologues appear to have diverged from the ferric reductase family, retaining overall transmembrane architecture, NAD(P), flavin adenine dinucleotide (FAD) and possibly haem-binding domains. Based on our results, we propose that TmpA is a membrane oxidoreductase involved in the synthesis of a developmental signal.