Larval vision contributes to gregarious settlement in barnacles: adult red fluorescence as a possible visual signal.

Gregarious settlement, an essential behavior for many barnacle species that can only reproduce by mating with a nearby barnacle, has long been thought to rely on larval ability to recognize chemical signals from conspecifics during settlement. However, the cyprid, the settlement stage larva in barnacles, has one pair of compound eyes that appear only at the late nauplius VI and cyprid stages, but the function(s) of these eyes remains unknown. Here we show that cyprids of the intertidal barnacle Balanus (=Amphibalanus) amphitrite can locate adult barnacles even in the absence of chemical cues, and prefer to settle around them probably via larval sense of vision.

Quantitative proteomics study of larval settlement in the Barnacle Balanus amphitrite.

Barnacles are major sessile components of the intertidal areas worldwide, and also one of the most dominant fouling organisms in fouling communities. Larval settlement has a crucial ecological effect not only on the distribution of the barnacle population but also intertidal community structures. However, the molecular mechanisms involved in the transition process from the larval to the juvenile stage remain largely unclear.

iTRAQ-based proteomic profiling of the barnacle Balanus amphitrite in response to the antifouling compound meleagrin.

Marine biofouling refers to the unwanted accumulation of fouling organisms, such as barnacles, on artificial surfaces, resulting in severe consequences for marine industries. Meleagrin is a potential nontoxic antifoulant that is isolated from the fungus Penicillium sp.; however, its mechanistic effect mode of action on larval settlement remains unknown.

Evidence for the involvement of p38 MAPK activation in barnacle larval settlement.

The barnacle Balanus ( = Amphibalanus) amphitrite is a major marine fouling animal. Understanding the molecular mechanism of larval settlement in this species is critical for anti-fouling research. In this study, we cloned one isoform of p38 MAPK (Bar-p38 MAPK) from this species, which shares the significant characteristic of containing a TGY motif with other species such as yeast, Drosophila and humans.

Transcriptomic analysis of neuropeptides and peptide hormones in the barnacle Balanus amphitrite: evidence of roles in larval settlement.

The barnacle Balanus amphitrite is a globally distributed marine crustacean and has been used as a model species for intertidal ecology and biofouling studies. Its life cycle consists of seven planktonic larval stages followed by a sessile juvenile/adult stage. The transitional processes between larval stages and juveniles are crucial for barnacle development and recruitment.

Structural optimization and evaluation of butenolides as potent antifouling agents: modification of the side chain affects the biological activities of compounds.

A recent global ban on the use of organotin compounds as antifouling agents has increased the need for safe and effective antifouling compounds. In this study, a series of new butenolide derivatives with various amine side chains was synthesized and evaluated for their anti-larval settlement activities in the barnacle, Balanus amphitrite. Side chain modification of butenolide resulted in butenolides 3c-3d, which possessed desirable physico-chemical properties and demonstrated highly effective non-toxic anti-larval settlement efficacy.

The regulatory role of the NO/cGMP signal transduction cascade during larval attachment and metamorphosis of the barnacle Balanus (=Amphibalanus) amphitrite.

The barnacle Balanus amphitrite is among the most dominant fouling species on intertidal rocky shores in tropical and subtropical areas and is thus a target organism in antifouling research. After being released from adults, the swimming nauplius undertakes six molting cycles and then transforms into a cyprid. Using paired antennules, a competent cyprid actively explores and selects a suitable substratum for attachment and metamorphosis (collectively known as settlement).

Possible molecular mechanisms of species recognition by barnacle larvae inferred from multi-specific sequencing analysis of proteinaceous settlement-inducing pheromone.

Gregarious settlement is essential for reproduction and survival of many barnacles. A glycoprotein, settlement-inducing protein complex (SIPC) has been recognized as a signal for settlement and it is expressed in both conspecific adults and larvae. Although the settlement-inducing activities of SIPC are species-specific, the molecular-based mechanism by which larvae distinguish conspecific SIPC from the SIPC of other species is still unknown.

Expression of calmodulin and myosin light chain kinase during larval settlement of the Barnacle Balanus amphitrite.

Barnacles are one of the most common organisms in intertidal areas. Their life cycle includes seven free-swimming larval stages and sessile juvenile and adult stages. The transition from the swimming to the sessile stages, referred to as larval settlement, is crucial for their survivor success and subsequent population distribution.

Toward an understanding of the molecular mechanisms of barnacle larval settlement: a comparative transcriptomic approach.

Background: The barnacle Balanus amphitrite is a globally distributed biofouler and a model species in intertidal ecology and larval settlement studies. However, a lack of genomic information has hindered the comprehensive elucidation of the molecular mechanisms coordinating its larval settlement. The pyrosequencing-based transcriptomic approach is thought to be useful to identify key molecular changes during larval settlement.

Species-specific detection and quantification of common barnacle larvae from the Japanese coast using quantitative real-time PCR.

Species-specific detection and quantification methods for barnacle larvae using quantitative real-time polymerase chain reaction (qPCR) were developed. Species-specific primers for qPCR were designed for 13 barnacle species in the mitochondrial 12S ribosomal RNA gene region. Primer specificity was examined by PCR using template DNA extracted from each of the 13 barnacle species, other unidentified barnacle species, and field collected zooplankton samples.

Purification and partial amino acid sequence analysis of the larval settlement-inducing pheromone from adult extracts of the barnacle, Balanus amphitrite (=Amphibalanus amphitrite).

A previously undescribed larval settlement-inducing protein was purified from adult extracts of the barnacle, Balanus amphitrite (=Amphibalanus amphitrite). Results of SDS-PAGE indicated that the relative molecular mass of the protein in reduced and denatured form is 31,600 +/- 500 kDa, and that it is distinct from the Settlement Inducing Protein Complex (SIPC) which has previously been determined as a larval settlement-inducing pheromone. The N-terminal 33-residue sequence of the intact protein showed no similarity with previously reported proteins in the EMBL/Genbank/DDBJ databases.

Larval development and settlement of a whale barnacle.

Larval development and settlement of whale barnacles have not previously been described, unlike intertidal barnacles. Indeed, the mechanisms of the association between barnacles and whales have not been studied. Here we describe the larval development and settlement of the whale barnacle, Coronula diadema, and possible involvement of a cue from the host in inducing larval settlement.

An alpha2-macroglobulin-like protein is the cue to gregarious settlement of the barnacle Balanus amphitrite.

Many benthic marine invertebrates, like barnacles, have a planktonic larval stage whose primary purpose is dispersal. How these species colonize suitable substrata is fundamental to understanding their evolution, population biology, and wider community dynamics. Unlike larval dispersal, settlement occurs on a relatively small spatial scale and involves larval behavior in response to physical and chemical characteristics of the substratum.

Does Phospholipase A Participate in the Acrosome Reaction of Sea Urchin Sperm?: A Pharmacological Study: (phospholipase A /acrosome reaction/quinacrine/p-bromophenacyl bromide/melittin).

We examined whether phospholipase A (PLA ) is involved in the initiation of the acrosome reaction of sperm of the sea urchin, Strongylocentrotus intermedius, using inhibitors and an activator of this enzyme. Quinacrine and p-bromophenacyl bromide (PBPB) inhibited the egg jelly-induced acrosome reaction at 100 μM, but not the ionomycin-induced one. Depression of egg jelly-induced increase of intracellular free Ca concentration ([Ca ] ) by these reagents was expected and examined using fura 2.

Activation of Proteasome in Sea Urchin Sperm by Lysophosphatidylinositol and by Sperm Lipids: (proteasome/sea urchin/sperm/acrosome reaction/lysophospholipid).

Effects of phospholipids, their metabolites and endogenous sperm lipids on the chymotrypsin-like activity of proteasome purified from sperm of the sea urchin, Strongylocentrotus intermedius were examined. Some lysophospholipids remarkably enhanced the activity. The most prominent activation was found in lysophosphatidylinositol (LPI) which enhanced about 12-fold at 2.