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Foundation species provide critical resources to ecological community members and are major determinants of biodiversity. The barnacle Balanus glandula is one such species and dominates space among the higher reaches on wave-swept shores. Here, we show that B. glandula produces a 199.6-kDa glycoprotein (named "MULTIFUNCin"), and following secretion, a 390-kDa homodimer in its native state. MULTIFUNCin expression is localized in the epidermis, cuticle, and new shell material. Consequently, this molecule can specify upon contact the immediate presence of a live barnacle. Shared, conserved domains place MULTIFUNCin in the α2-macroglobulin (A2M) subgroup of the thioester-containing protein family. Although previously undescribed, MULTIFUNCin shares 78% nucleotide sequence homology with a settlement-inducing pheromone (SIP) of the barnacle, Amphibalanus amphitrite Based on this and further evidence, we propose that the two proteins are orthologues and evolved ancestrally in structural and immunological roles. More recently, they became exploited as chemical cues for con- and heterospecific organisms, alike. MULTIFUNCin and SIP both induce habitat selection (settlement) by conspecific barnacle larvae. In addition, MULTIFUNCin acts as a potent feeding stimulant to major barnacle predators (sea stars and several whelk species). Promoting immigration via settlement on the one hand, and death via predation on the other, MULTIFUNCin simultaneously mediates opposing demographic processes toward structuring both predator and prey populations. As a multifunctional protein cue, MULTIFUNCin provides valuable sensory information, conveys different messages to different species, and drives complex biotic interactions.

Foundation species provide critical resources to ecological community members and are key determinants of biodiversity. The barnacle Balanus glandula is one such species and dominates space among the higher reaches of wave-swept shores (Northeastern Pacific Ocean). This animal produces a cuticular glycoprotein (named "MULTIFUNCin") of 199.6 kDa, and following secretion, a 390 kDa homodimer in native form. From field and lab experiments, we found that MULTIFUNCin significantly induces habitat selection by conspecific larvae, while simultaneously acting as a potent feeding stimulant to a major barnacle predator (whelk, Acanthinucella spirata). Promoting immigration via settlement on the one hand, and death via predation on the other, MULTIFUNCin drives opposing demographic processes toward structuring predator and prey populations. As shown here, a single compound is not restricted to a lone species interaction or sole ecological function. Complex biotic interactions therefore can be shaped by simple chemosensory systems and depend on the multifunctional properties of select bioactive proteins.

An increasing body of evidence suggests a significant genetic regulation of inflammatory response mechanisms; however, little is known regarding the genetic determinants of severe gingival inflammation (GI). We conducted a genome-wide association study of severe GI among 4077 European American adults, participants in the Dental Atherosclerosis Risk In Communities cohort. The severe GI trait was defined dichotomously using the 90 th percentile of gingival index ≥2 extent score. Genotyping was performed with the Affymetrix 6.0 array platform and an imputed set of 2.5 million markers, based on HapMap Phase II CEU build 36, was interrogated. Genetic models were based on logistic regression and controlled for ancestry (10 principal components), sex, age, and examination center. One locus on chromosome 17 met genome-wide statistical significance criteria-lead single nucleotide polymorphism (SNP): rs11652874 [minor allele frequency=0.06, intronic to ASIC2 (acid sensing ionic channel-2, formerly named ACCN1 ); odds ratio=2.1, 95% confidence interval=1.6-2.7, p=3.9×10 -8 ]. This association persisted among subjects with severe periodontitis and was robust to adjustment for microbial plaque index. Moreover, the minor [G] allele was associated with higher levels of severe GI in stratified analyses among subsets of participants with high load of either "red" or "orange" complex pathogens, although this association was not statistically significant. While these results will require replication in independent samples and confirmation by mechanistic studies, this locus appears as a promising candidate for severe gingival inflammation. Our findings suggest that genetic variation in ASIC2 is significantly associated with severe gingival inflammation and the association is plaque-independent.

Background: Atrial tachycardia (AT) that develops after ablation of atrial fibrillation often poses a more difficult clinical situation than the index arrhythmia. This study details the use of an impedance-based electroanatomic mapping system (Ensite NavX) in concert with a specialized multielectrode mapping catheter for rapid, high-density atrial mapping. In this study, this activation mapping was combined with entrainment mapping to eliminate ATs developing late after atrial fibrillation ablation., Methods and Results: All study patients developed AT after ablation for atrial fibrillation. The approach to AT ablation consisted of 4 steps: use of a 20-pole penta-array catheter to map the chamber rapidly during the rhythm of interest, analysis of the patterns of atrial activation to identify wave fronts of electric propagation, targeted entrainment at putative channels, and catheter ablation at these "isthmuses." All ablations were performed with irrigated radiofrequency ablation catheters. Forty-one ATs were identified in 17 patients (2.4+/-1.6 ATs per patient). Using the multielectrode catheter in conjunction with the Ensite NavX system, we created activation maps of 33 of 41 ATs (81%) (mean cycle length, 284+/-71 seconds) with a mean of 365+/-108 points per map and an average mapping time of 8+/-3 minutes. Of the 33 mapped ATs, 7 terminated either spontaneously or during entrainment maneuvers. Radiofrequency energy was used to attempt ablation of 26 ATs; 25 of 26 of the ATs (96%) were terminated successfully by ablation or catheter pressure., Conclusions: This study demonstrates a strategy for rapidly defining and eliminating the scar-related ATs typically encountered after ablation of atrial fibrillation.